Shifting physical activity patterns among women: The historical and potential future impacts on pelvic floor and skeletal health

Successes in the battle for gender equality have helped empower women to become more physically active through exercise and sport in recent times than any other point in history, particularly since the passage of Title IX. As a result, many women are choosing programs of high intensity with impact, some of which have only gained popularity in the last decade. These activity trends elicit different health effects, both acute and long term. This paper seeks to explore historical trends in women's physical activity (PA), pelvic floor health, and skeletal health. Using current research, it aims to identify some of the potential long term health effects for women engaging in high intensity activities. The links between PA to load bones and improve bone mineral density are well demonstrated; however, the long term effects of PA on pelvic floor health are still under investigation. The types of PA that promote bone health may or may not also promote pelvic floor health. This paper seeks to examine the most current research so clinicians, health educators and fitness professionals may understand how these conditions may affect their clients and patients so they may make the best recommendations for PA in order to facilitate long term skeletal and pelvic floor health for women of all ages.

SHIFTING PHYSICAL ACTIVITY PATTERNS AMONG WOMEN: THE HISTORICAL AND POTENTIAL FUTURE IMPACTS ON PELVIC FLOOR AND SKELETAL HEALTH by Alexis Pearl Lee A Senior Honors Thesis Submitted to the Faculty of The University of Utah In Partial Fulfillment of the Requirements for the Honors Degree in Bachelor of Science In Exercise and Sport Science Approved: ______________________________ Janet M. Shaw, PhD Thesis Faculty Supervisor _____________________________ Janet M. Shaw, PhD Chair, Department of Exercise and Sport Science _______________________________ Kerry Jacques, MS Honors Faculty Advisor _____________________________ Sylvia D. Torti, PhD Dean, Honors College April 2016 Copyright © 2016 All Rights Reserved ii ABSTRACT Successes in the battle for gender equality have helped empower women to become more physically active through exercise and sport in recent times than any other point in history, particularly since the passage of Title IX. As a result, many women are choosing programs of high intensity with impact, some of which have only gained popularity in the last decade. These activity trends elicit different health effects, both acute and long term. This paper seeks to explore historical trends in women’s physical activity (PA), pelvic floor health, and skeletal health. Using current research, it aims to identify some of the potential long term health effects for women engaging in high intensity activities. The links between PA to load bones and improve bone mineral density are well demonstrated; however, the long term effects of PA on pelvic floor health are still under investigation. The types of PA that promote bone health may or may not also promote pelvic floor health. This paper seeks to examine the most current research so clinicians, health educators and fitness professionals may understand how these conditions may affect their clients and patients so they may make the best recommendations for PA in order to facilitate long term skeletal and pelvic floor health for women of all ages. iii TABLE OF CONTENTS ABSTRACT ii INTRODUCTION 1 DEFINITIONS 2 PHYSICAL ACTIVITY, EXERCISE AND SPORT 2 PELVIC FLOOR DISORDERS 2 SKELETAL HEALTH DISORDERS 7 THE HISTORY WOMEN AND PHYSICAL ACTIVITY 10 PRE-TITLE IX VICTORIAN ERA (1840-1900) 10 PRE-TITLE IX (1900-1972) 14 POST-TITLE IX (1972-PRESENT) 17 PELVIC FLOOR DISORDERS 22 SKELETAL HEALTH DISORDERS 26 PERSPECTIVES OF HISTORICAL PA, PFDS AND OP 36 THE IMPACT OF PA ON PELVIC FLOOR HEALTH 39 THE IMPACT OF PA ON SKELETAL HEALTH 46 PELVIC FLOOR VS. SKELETAL HEALTH: ARE THEY AT ODDS? 51 SUGGESTIONS FOR HEALTH AND FITNESS PROFESSIONALS 53 ACKNOWLEDGMENTS 55 REFERENCES 56 1 INTRODUCTION My thesis on women’s physical activity patterns historical and potential future impacts on skeletal and pelvic floor health is written with experts in Kinesiology and lay people as the intended audience. Kinesiology experts are likely familiar with concepts presented herein; however, as an honors thesis, I feel this paper has the potential to be read by students in a variety of fields to help inform their understanding of women’s participation in PA and potential long term health outcomes of such participation with respect to skeletal and pelvic floor health. Therefore, I have attempted to fully explain concepts for those outside of the sport sciences, starting with definitions of the three main components of this paper: physical activity, exercise and sport; pelvic floor health; and skeletal health. Along with definitions, the current trends and predictions for these health outcomes portray their looming public health burden. Following the definitions of these three main concepts, I have provided an historical overview. The issues of today remain linked to the happenings of the past, and historical trends can help paint a picture of understanding for current situations. First, I explore women’s participation in sport and PA and follow up with the history of women’s skeletal and pelvic floor health. At the culmination of this section, I attempt to discern trends that help demonstrate how historic rates of PA may have impacted the development of pelvic floor disorders or osteoporosis. With a foundation of historical knowledge, modern research is presented with an examination of the effect of PA on pelvic floor and skeletal health. Finally, I will explore the potential relationship between pelvic floor and skeletal health. I conclude with some basic suggestions for clinicians, health educators, and fitness professionals. 2 DEFINITIONS DEFINITIONS OF PHYSICAL ACTIVITY, EXERCISE AND SPORT Within the context of this paper, it is important to distinguish between a few important topics related to PA. Physical activity has been defined as ‘any bodily movement produced by skeletal muscles that results in energy expenditure’ (Caspersen, Powell & Christenson, 1985, p. 126). Both exercise and sports can be considered subsets of PA. Exercise is defined as ‘a subset of PA that is planned, structured, and repetitive and has a final or an intermediate objective of the improvement or maintenance of physical fitness’ (Caspersen, Powell & Christenson, 1985, p. 126). Sport is defined as ‘a contest or game in which people do certain physical activities according to a specific set of rules and compete against each other’ (Merriam Webster, n.d.). A great deal of the research surrounding women and PA has been conducted in sports. It serves as a solid foundation of knowledge, though some results of sports research may not be applicable to general physical activity. DEFINITIONS OF PELVIC FLOOR DISORDERS A basic understanding of pelvic floor anatomy is necessary. In a most simple metaphor, the pelvic floor is like a muscular hammock that sits just above the pelvis and supports all of the pelvic organs. In more accurate anatomical terms, the pelvic floor is made up of various structures including muscular and fibrous components. The pelvic floor closes the ‘bony pelvic outlet’ that forms a bony ring. In women, the ring-like 3 opening of the pelvis is typically wider than observed in men, which facilitates childbirth. The outermost or most caudal layer is made of up of the skin on the external genitalia and the inner layer is made up of the pelvic organs (DeLancey, 1992). The layers in between are made up of muscles including the levator ani, urogenital sphincter, and external anal sphincter, ischiocavernosus, and bulbospongiosus. These muscles make up the ‘hammock’ of the pelvic floor; their function is to support the pelvic organs, which they do through contraction and relaxation. If intra-abdominal pressure rises, pelvic viscera will get pushed down, and these muscles must contract to resist the downward force, pushing the organs up and keeping them in their proper place. The ability to contract pelvic floor muscles is what prevents involuntary urinary and fecal incontinence. Similarly, the relaxation of these muscles allow for the evacuation of urine or feces. For women, the urethra, vagina and rectum pass through all of the layers of the pelvic floor until they open on the outside of the body. Because the pelvic floor surrounds these structures, it plays an important role in the functions of the urethra, vagina and rectum. Pelvic floor dysfunction includes a variety of disorders that for the most part are sex specific, affecting primarily women. Pelvic Floor Disorders (PFDs) most commonly affect the urethra, vagina and rectum--the outlet structures surrounded and modulated by the pelvic floor. PFDs include urinary and fecal incontinence, prolapse of the pelvic organs, dysfunctions, abnormalities and chronic pain of the pelvic organs (Sung & Hampton, 2009). In this paper, I will focus on urinary incontinence (UI) and pelvic organ prolapse (POP). POP is confirmed when one of the pelvic organs-- the bladder [anterior], uterus [apical] or rectum [posterior] ‘prolapse’ or fall out of place and begin to come into and out of the vagina. Prolapse is diagnosed in stages using a standardized system created 4 by the International Continence Society, the POP Q, which measures tissues in centimeter relative to the hymen with negative numbers representing points above the hymen and positive numbers representing points below or past the hymen (Bump et al., 1996). A score of -3 indicates the best support or no prolapse, a score of 0 is at the hymen. In general, prolapse is defined as a descent of stage I or greater’ (Weber, et al., 2001). Women diagnosed with Stage I POP may feel as though there is a ‘bulge’ in the vagina whereas women with ‘complete’ or Stage IV POP will have tissue such as the entirety of the uterus protruding from the vagina, even at rest. While some women may be asymptomatic, many women are acutely aware of the changes in their pelvic region and find this condition extremely painful, uncomfortable and embarrassing. Current treatments include physical therapy, the use of a pessary, a device placed in the vagina to hold the pelvic organs in situ, and surgery. Urinary incontinence (UI), another common PFD, is most generally defined as ‘involuntary loss of urine’ and previous definitions have also included the caveat ‘that the incontinence is both objectively demonstrable and a social or hygienic problem for the patient’ (Weber, et al., 2001). UI can take the form of stress urinary incontinence (SUI) or urge urinary incontinence (UUI). Examples of SUI are when a woman involuntarily loses urine as a result of some kind of physical exertion, which can range from sneezing, coughing, jumping rope, running or lifting a heavy object. Women with severe SUI can lose large amounts of urine just by standing from a seated position. Essentially, these symptoms signify the pelvic floor muscles’ inability to contract sufficiently to counteract the concomitant rise in intra-abdominal pressure associated with the activity (Weber, et al., 2001). On the other hand, UUI is usually preceded by a sense of urgency, some 5 symptoms include frequent urination, waking from sleep to urinate or loss of urine in sleep (Weber, et al., 2001). Though UUI can be challenging to manage during exercise, PA has not been implicated in the development of UUI; therefore, a greater emphasis will be placed on SUI, where PA has been implicated as a potentially modifiable risk factor. PFDs of all varieties, including those discussed in this paper, present a major public health problem. Though more research is needed, it is currently thought that multiple pregnancies [high parity], vaginal deliveries, vaginal delivery of a large baby, straining to void, strenuous PA, repetitive heavy lifting, loss of estrogen in menopause, and aging are factors that influence the development of PFDs (Wu et al., 2014; Nygaard, et al., 2008). Approximately 25% of women across the United States are estimated to have one or more symptomatic PFDs. Using National Health and Nutrition Examination Survey (NHANES) data from 2005-2006, 2007-2008, and 2009-2010, nearly 8,000 women were categorized as having UI, Fecal Incontinence or POP (Wu et al., 2014). Prevalence rates from 2005-2010 were analyzed, and during those five years there were no noticeable trends positively or negatively. However, researchers project that PFDs will increase markedly from now until 2050 due to shifting demographics and the aging population of the United States (Wu et al., 2014). The population of older adults is projected to multiply, with nearly 84 million people older than 65 by 2050; more specifically, the 85+ portion of the population is estimated to triple from 5.9 million in 2012 to nearly 18 million in 2050 (Ortman et al., 2014). Additionally, women tend to outlive men, which indicates there will be substantially more elderly women in the U.S. than ever before (Ortman et al., 2014; Wu et al., 2009). The shift in demographics likely means a parallel rise in PFDs because 6 PFDs are more common as women age. Data from NHANES indicate approximately 7% of women aged 20-29 years compared to 53% of women older than 80 years have one or more symptomatic PFDs (Wu et al., 2014). It is projected by 2050 approximately 30 million women will have at least one PFD, though ‘worst-case scenario’ estimates are as high as 58 million, which would mean that one in every three women projected to be alive in 2050 will have a PFD. The public health burden of PFDs is serious, both in terms of quality of life and in terms of economics. Reviews of the literature indicate that UI can seriously decrease a woman’s quality of life, particularly in ‘four main dimensions including: physical health, mental health, sexual health and social well-being’ (Sushan & Muliira, 2014, p.62). The cost of care for PFDs is substantial. Based on projections from Kaiser Permanente in Southern California, the number of consultations alone for PFDs is expected to increase nearly 45% from 2000 to 2030, from 618,165 to 954,397 (Wu et al., 2009). Additionally, surgery is becoming an increasingly common form of treatment. By the age of 80, the lifetime risk of having had a corrective surgery for incontinence or prolapse is 11.1% (Wu et al., 2009). In 2009, an estimated 303,500 surgeries were performed for UI, POP and fecal incontinence. These surgeries are not always effective, and unfortunately nearly a third of women must endure a repeat surgery to treat the same issue (Wu et al., 2009). Higher prevalence rates of PFDs are associated with more medical consultations, surgeries, poor surgical outcomes and repeat surgeries. Given the impact of PFDs, understanding any possible modifiable risk factors, such as physical activity, and implementing any preventive or treatment measures is paramount to the health and happiness of the future women of America. 7 DEFINITONS OF SKELETAL HEALTH DISORDERS Prior to an examination of the serious skeletal health disorder, osteoporosis (OP), a background of skeletal makeup and physiology is given here. The bones of the skeleton are living tissues that have the capacity to change constantly, though changes are often only noticeable in cycles of three to four months (Bailey & Brooke-Wavell, 2010). The main functions of bone include the ‘provision of mechanical integrity for locomotion and protection’, the storage of bodily calcium and ‘associated involvement of metabolic pathways of mineral’ balance, and hematopoiesis, or the production of blood cells including those that support immune function (Morgan, Barnes & Einhorn, 2013, p.3). Bone is made up of an inner, soft layer known as spongey or trabecular bone and an outer hard layer known as cortical bone. Bone is dynamic in nature due to its frequent remodeling, where bone is broken down through resorption and created through osteogenesis (Morgan, Barnes & Einhorn, 2013). Osteogenesis is performed by osteoblasts, the cells that help lay down new bone, whereas osteoclasts are the cells responsible for resorption. Osteocytes are former osteoblasts that get trapped in the mineralization process. Osteocytes play a key role in bone remodeling because they have dendritic extensions that are sensitive to the stimulus of PA, and begin the signaling process to increase osteogenesis in response to that mechanical signal. A variety of factors including PA, nutrition, reproductive hormones and aging, affect the rate at which bone is remodeled and will be discussed over the course of this paper (Eastell, 2013). When bone is being created at a greater rate than it is being 8 catabolized, it is in positive bone balance. Conversely, when bone is being torn down faster than it is being built, it is in negative bone balance. Bone accretion is greatest before age 30, at which point skeletal maturity is reached. Persistent negative bone balance can lead to poor skeletal health and conditions such as osteopenia, defined as low bone mass, and OP. OP is defined as a ‘progressive systemic skeletal disease characterized by low bone mass and micro-architectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture’ (Consensus Development Conference, 1991, p.107). OP can be prevented in several ways, including building up bone during youth (<30 years) so that there is a ‘cushion’ of what can be depleted before becoming osteoporotic after reaching skeletal maturity. Another method to prevent the risk of OP fracture is to mitigate bone loss in adulthood, so bone is lost slowly enough that OP never develops. Osteopenia and OP are significant health concerns for the aging population of the United States. In 2010 it was estimated that nearly 10% of US adults over 50 years were diagnosed with OP, which is approximately 10.2 million people. An additional 43 million adults were estimated to suffer from low bone mass in 2010, for a combined 53 million people affected by low bone mass and OP. Although research from the National Osteoporosis Foundation (NOF) indicates that rates of OP decreased from 2002 to 2010, it appears there was an increase in prevalence of osteopenia, which can eventually lead to OP (National Osteoporosis Foundation). By 2030, the number of adults over 50 years with OP is projected to increase to 13.6 million, with an additional 57.8 million affected by low bone mass (National Osteoporosis Foundation). 9 If there were no problems associated with low bone mass and OP, these statistics would not be so concerning. OP is associated with a much higher risk for fracture. In fact, fractures in older people with low bone mass happen frequently with 1.5 million occurring each year (Surgeon General’s Report, 2012). While fractures are painful, there are additional costs and consequences. About a fifth of people with hip fractures end up in some form of assisted living facility, and for elderly persons, the likelihood of death in the three months following the fracture is quadrupled (Surgeon General’s Report,2012). The costs associated with the care of OP and fractures are high with estimated totals reaching nearly $18 billion annually (Surgeon General’s Report, 2012). Similarly to PFDs, the risk of developing OP increases with age and increases disproportionately in women compared to men. For example, in Latin American countries, nearly 40% of women over 80 years old are osteoporotic compared with about 7% of women aged 50-59 (Clark, et al., 2000). OP is a serious condition that is expected to affect greater and greater proportions of Americans. PA has been shown to improve bone growth and mitigate bone loss; thus, understanding the potential impact of PA and windows of opportunity is imperative to maintaining the skeletal health of Americans. For these reasons, skeletal health is one of the main long term health consequences this thesis seeks to examine. 10 THE HISTORY THE HISTORY OF WOMEN AND PHYSICAL ACTIVITY As a result of gender norms and ideals, women’s participation in sport and PA in America has historically been restricted. The passage of Title IX in 1972 has been hugely influential in enabling equity between men and women by forcing societal recognition of women’s right to participate in sport and PA, and has simultaneously played a large role in shifting gender norms and expectations for women to be physically active (Bell, 2008). Although sports, such as those affected by Title IX implementation, differ from PA and exercise in the sense that sports are generally organized, rule-bound and competitive. Sport typically sets the stage for what is considered ‘normal’ training in the realms of exercise and PA. Following is historical context for women’s expected participation in self-selected sport, exercise and/or PA, divided into Pre-Title IX and Post-Title IX eras. THE HISORY OF WOMEN AND PA: Pre-Title IX- The Victorian Era 1840-1900 This examination of the American gender norms for women and the impact on women’s participation in sport will begin with the Victorian Era in the latter half of the nineteenth century. During this time, women were not just the other sex, they were considered the finer sex; they were not just women, but ladies. The ideal Victorian woman was fragile, virtuous, ailing, virginal, beautiful and altruistic. Victorian women were expected to be quiet, obedient, and subservient to men, particularly to their husbands (Donnelly, 1986). Victorian women were divided into various socio-economic groups. There were upper-class, middle-class, lower-class, under-class, and slave women. These different 11 classes played a large role in determining the types of activities in which a woman of any subgroup would participate. Upper class women rarely worked outside of the home, and in some cases were able to hire outside help to complete their domestic duties of cooking and cleaning. Thus, these women had the ability to spend plenty of time perfecting themselves so they more closely resembled the Victorian ideal. In contrast, middle-lower class women often had to work. Professions for women during this era varied greatly from teaching, to sewing, to occasionally working in factories. Within the home, the domestic duties that accompanied marriage and families for many women who were not affluent or who were enslaved were not particularly delicate. Activities such as ‘work[ing] the fields, hand-wash[ing] clothing, and toil[ing] over kitchen stoves bore little relation to the Victorian conception of women’ (Gerber, 1974, p. 10). In the Victorian Era ‘to have facial color and muscular strength was a sign of having to work for a living,’ and was accordingly frowned upon by society (Gerber, 1974, p. 10). This highlights an important concept that in some ways has flipped today. Toned and tanned bodies are now considered to be the ideal. Ironically, it is usually affluent women who can more readily attain this ideal than those who are impoverished. To be tanned and toned are no longer results of the labors of living, but rather from intentional exercise and PA. Outside of domestic labors, women’s participation in PA and sport was just beginning in the late 1800s, although it was infrequent. During the Victorian Era, sport was not particularly intense for either men or women. The low vigor of sports can be attributed to a number of things. Clothing of this era, both for men and women was not conducive to agile, quick movement. For both sexes, it was improper to sweat, breathe 12 hard, and show intense emotions. Thus, sports emphasized recreational rather than competitive involvement (Bell 2008; Gerber 1974). Surprisingly, the recreational nature of sports in the Victorian era opened the door for women and men to be active together. Because women needed to maintain their chastity, purity, and innocence; women required wholesome ways to engage their male counterparts. Sports were often seen as just this: an opportunity for morally appropriate social encounters between the sexes. Sports such as croquet, tennis, ice skating and golf were all activities that men and women could both engage in, ‘since the skill level and effort was not high for either sex, it was feasible for men and women to compete with one another individually or in couples’ (Gerber, 1974, p. 4). Outside of these sporting dates, women were particularly discouraged from vigorous activity and sport involvement as a result of gender norms that emphasized women’s weakness, delicacy, purity, fertility and beauty. ‘By avoiding exercise and cultivating a pale face and an incapacity to do work, one gave the appearance of gentility’ (Gerber, 1974, p10). Gentility and beauty were the pillars of womanhood during this age. Women were expected to remain pure until marriage and then to be obedient to their husbands in marriage. Part of this obedience, and one of the largest expectations placed on women, was their ability to bear and care for children. Therefore, the ‘Victorian ideal was antithetical to sport… by exposing the face and reproductive organs to possible injuries, sport endangered the ultimate Victorian goal: the twin functions of attracting a man and bearing a child’ (Gerber, 1974, p. 12). It is important to explore how women’s reproductive capacities have always played an extensive role in establishing gender norms for activities of all sorts, but 13 particularly physically strenuous activities. Women were discouraged from engaging in almost anything during their menstrual cycles. Due to ‘periodic weakening’ women were discouraged from ‘both muscular and brain labor’ at the ‘onset of menstruation’ (Clarke, 1874). Of course this ‘periodic weakening’ embodied the Victorian ideal of weakness and fragility, so it is logical that some women may have exaggerated their symptoms, intentionally contributing to this notion of frailty during menses. During menstruation, it was also thought that the ‘uterus [was] physiologically congested and temporarily abnormally heavy and hence, liable to displacement by the inexcusably strenuousity and roughness of [sport]’ (Gerber, 1974, p. 16). The relationship between menstruation and uterine health was also noted: ‘most important of all was the possibility that vigorous sport might cause the number, extent, and flow of menstruations to be reduced, in turn engendering a decrease in fertility due to a attendant decrease in the size of the uterus (function makes the organ)’ (Gerber, 1974, p. 13). There was concern for the exposure of women’s reproductive organs to traumas of physical contact sports. It was also commonly thought that the exertion itself may render a woman unable to bear children, due to ‘pelvic disturbances’ such as POP. If a primary value of women to society was the ability to reproduce, it would make sense in this historical context to recommend that women avoid strenuous exercise to preserve reproductive health. The ability to bear children has always been and will always be a part of a woman’s reality. Therefore, it is still of utmost importance to promote women’s reproductive and pelvic floor health. Poor reproductive and pelvic floor health has far reaching impacts into many of the dimensions of health including social, mental, economic, and sexual. Therefore, elucidating the potential effects of PA on pelvic floor 14 health is not solely about disproving supposedly ‘antiquated’ ideas of endangering females’ reproductive capacities, but in truly ensuring that sound scientifically-based practices are recommended for PA, exercise and sport. THE HISOTRY OF WOMEN AND PA: Pre-Title IX- 1900-1972 Through the end of the 19th century and into the beginning of the 20th century, women began to enjoy more sports involvement through formal and informal athletic clubs. Some women were able to join existing men’s clubs and enjoy separated activities, although they were never accorded full club membership status (Bell, 2008). Other clubs were exclusive to women such as ‘the Ladies’ Club of Outdoor Sports,’ which was founded in 1877 with a small contingent of 30 women who eventually branched off from its original men’s club counterpart (Gerber, 1974, p. 27). These athletic clubs spanned from New Orleans to New York and sponsored activities such as croquet, tennis, baseball, bowling, archery, cycling, rowing, golf and fencing (Bell, 2008; Gerber, 1974). While early athletic clubs for women were originally recreational in nature, the activities transformed ‘sport.’ In the beginning of the twentieth century, national sport organizations began to play a larger role in the regulation of women’s sports. Following the success of the motion to support women’s swimming and track and field in 1922, the Amateur Athletic Union (AAU) moved to support women in all sports starting in 1923. Unfortunately, female would-be-sport-participants were battling societal opposition, and participation didn’t increase as the AAU expected. They were encouraged to shift their attention to ‘industrial and recreation groups’ (Gerber, 1974). Industrial sport of the time 15 partially consisted of employee sponsored recreational options; large corporations would have clubs and office-teams. One of the most cited sports is basketball, although volleyball was also popular. In the late 1940s the Illinois Bell Telephone Company boasted nearly 1000 female employees on in-office volleyball teams (Gerber 1974). Other noteworthy popular activities included bowling, softball, tennis and golf. During this same time period, college women’s participation in intramural sports was on the rise. By 1936, the most popular intramural sports were basketball, tennis, archery, swimming and baseball. Intramural sports formed the basis for undergraduate women’s participation, although it took time for intercollegiate competition to become accepted and gain popularity. The first ever documented competitive intercollegiate female athletics consisted of a series of basketball games in 1896 (Gerber, 1974). It would take nearly another half a century for intercollegiate female athletics to be promoted and recognized as the norm. Many colleges preferred intramural competition and cited a number of reasons for restricting contests between schools. Most commonly, sport was viewed as acceptable between classmates, but elevating competition and featuring varsity teams, which required greater skill, was dangerous and unwomanly. Specific examples from the Women’s Division of the National Amateur Athletic Federation (NAAF) creed include: To promote programs of physical activities for all members of given social groups rather than for a limited number chosen for their physical prowess. To avoid countenancing the sacrifice of an individual’s health for the sake of her participation in athletic competition. To discourage athletic competition that involves travel. To eliminate types and systems of competition which put the emphasis upon individual accomplishment and winning rather than upon stressing the enjoyment 16 of the sport and the development of sportsmanship among the many (Gerber, 1974, p. 72-73). Though this creed was originally penned in 1923, it wasn’t amended until 1957. Upon amendment, it was acknowledged by the newly formed group, the National Section for Girls and Women’s Sports (NSGWS) that ‘intercollegiate programs may existprovided they were at the top of the pyramid.’ As Gerber points out in her analysis of the position statement, this was most likely changed as an acceptance of reality since ‘a third of colleges were [already] conducting varsity programs’ rather than a foundation upon which to lay varsity groundwork (Gerber, 1974). Other mid-century events, such as World War II, had far reaching effects on women’s participation in activity. Times of crisis, like war, progress the role of women in society; during war, a country is forced to recognize its whole population, not just the half made up by men. As millions of men left jobs to join the military, many women joined the military alongside them or had to join the dwindling workforce. Women were told ‘We Can Do It’ from Rosie the Riveter, and indeed they found themselves capable of the tasks at hand. Major League Baseball was cancelled as a result of the war, so the first ever professional women’s athletic league was created in its place: The All-American Girls Baseball League (Bell, 2008). The decades following the war featured large shifts in America’s perception and recognition of minority groups. The Civil Rights movement and passage of the Civil Rights Act in 1964 helped elevate the position of women along with people of color. In 1963, the NSGWS further altered their position statements listed above to say intercollegiate athletic programs were ‘desirable’ (Gerber, 1974). The positive shifts in 17 attitude towards women’s athletics in conjunction with social reforms were the foundation of further legislation, most notably Title IX. THE HISTORY OF WOMEN AND PA: Post-Title IX- 1972-present Title IX of the Education Amendment was signed into law in 1972. It is a ‘comprehensive federal law that prohibits discrimination on the basis of sex in any federally funded education program or activity’ (Department of Justice). Title IX has ten key areas that extend far beyond athletics including access to higher education, career education, education for pregnant and parenting students, employment, learning environment, math and science, sexual harassment, standardized testing, and technology (Title IX Info). Athletic programs through high schools and colleges are considered federally funded education activities, making them subject to Title IX regulation. The three components of Athletics and Title IX (NCAA) are enumerated below. Institutions must meet these requirements in order to be compliant with Title IX. 1. Provision of equitable participation opportunities for men and women. 2. Fair division of scholarships proportional to participation. 3. Equitable provision of benefits such as coaching, facilities, and support services. Since the implementation of Title IX, female participation in school sponsored athletics has skyrocketed. ‘In 1972, only 295,000 girls competed in high school sports, whereas 3.67 million boys did. By 2010-2011 the number of girls playing had risen to 3.2 million and the number of boys to 4.5 million’ (National Women’s Law Center, 2012). 18 Similarly, participation at the university level has also risen dramatically. In 2012 there were 193,232 women competitors compared to a meager 32,000 in 1972. Despite large increases in school sport participation for women and girls, the playing field remains uneven between men and women, and also between privileged and disadvantaged women. Within high schools across the country, there is often a participation gap where the percentage of girls who participate in athletics is not equal to the proportion of girls within the school. On a collegiate level, the percentage of opportunities for women to participate in sport is not equal to the opportunities provided male athletes (National Women’s Law Center, 2012). Additionally, female athletes receive less funding in terms of recruitment spending and scholarships. Within elementary and secondary schools , nearly 76% of white girls play sports, but only 64% of black and Latina and 53% of Asian girls do. This discrepancy between white girls and girls of color is concerning, because girls of color are already less likely than their white counterparts to be physically active and participate in sports other than those sponsored by schools. Girls of color graduate at lower rates than white girls, and sport participation has shown to improve academic achievement such as graduation rates (National Women’s Law Center, 2012; Staurowsky et al., 2015). The numerous benefits of PA and sport participation that have come as a result of Title IX legislation are outlined below. The demonstrated advantages and positive long-term outcomes of sport participation place a burden on legislators, educators, and community members to ensure that opportunities for play are continually expanded and maintained for girls and women, especially for girls of color. 19 The impact of increased sport participation for women and girls cannot be understated. PA can improve the health of young girls in multiple dimensions, including physical, social, psychological, and academic. PA in adolescence has been shown to reduce risks of developing serious chronic conditions later in life such as breast cancer, cardiovascular disease, obesity, diabetes and hypertension (Staurowsky et al., 2015). A pattern of regular PA during adolescence and early adulthood may help prevent or delay the development of chronic diseases, and it may also help to establish life-long habits of behavior that will help maintain fitness and subsequent health benefits across the lifespan. Girls who participate in sports are less likely to engage in high risk behaviors such as smoking cigarettes, and engaging in drug use and under-age drinking (Staurowsky et al., 2015). Some research indicates that girls who engage in athletics take fewer sexual risks. For example, girls involved in sports are more likely to delay sexual initiation and use protection during sexual activity, and have fewer sexual partners (Dodge and Jaccard, 2002; Erkut and Tracy, 2000; Miller et al., 2000; Eitle and Eitle, 2002; Lehman and Koerner, 2004; Stuarowsky, 2015). Safer sex practices help prevent girls from contracting STIs that could impact their lifelong health and reduces rates of unintended pregnancy. Reduction of teenage pregnancy has many benefits from social and health perspectives. Preventing teenage pregnancy can also be protective of bone mass (Cho, 2012). There are multiple theories that explain reduced risky behavior among active girls, including improved self-esteem and self-empowerment to resist the pressures to partake in such activities. Girls may choose not to engage in risky behaviors because they recognize the long-term consequences may endanger their ability to play. Another 20 hypothesis is that participation in school sports and time spent directly after school narrows the time during which girls could experiment with risky behaviors (Staurowsky et al., 2015). In addition to the numerous physical health benefits and mitigation of risky behaviors, sport participation confers many mental health benefits. PA has been shown to work as an ‘anti-depressant’, both biochemically and psychologically (Staurowsky et al., 2015). Women and girls who are physically active have been shown to have fewer depressive symptoms than their less active counterparts. Further, young women who participate in organized sport report lower levels of depression, increased self-esteem, and better connections with peers compared to those who do not participate in organized sport. These positive effects of PA can be seen across the lifespan from children up to the elderly. Not only is PA effective in combatting depression at each stage of life, but it appears to have protective effects across the lifespan- people who were less active in their youth may have a higher risk of developing depression later in life (Jacka et al, 2011). There are many similar findings for anxiety. Compared to their less active counterparts, women who are active tend to have reduced symptoms of anxiety, and PA may provide a venue for social interaction which is a protective factor against developing anxiety disorders (Pasco et al., 2011). Sport participation has been shown to reduce girls’ likelihood to consider, plan or attempt suicide (Staurowsky et al., 2015, p. 86). However, there are also a number of studies that are beginning to indicate that motivation for involvement in exercise or sport or extreme pressures as a result of participation may be associated with higher levels of depression and suicidal ideation (Staurowsky et al., 2015). 21 PA and sport participation are positively correlated with educational outcomes. Girls who participate in sports enroll in more rigorous courses like AP classes; they were also more likely to take and do well in science and math classes. Participation in sport is also positively related to higher academic achievement in terms of higher grades, higher graduation rates, and higher intentions of attending college (Staurowsky et al., 2015). While there are many factors in addition to sports involvement that play a role in girls’ educational attainment, in a review of high school sport participation and education Hartmann noted ‘research has time and again demonstrated a strong and positive correlation between high school sports a number of studies have shown there is a strong positive correlation between high school sports participation and academic achievement’ (Hartmann, 2008, p. 3). Sports participation may not be directly causative of improved academics, but it may play a positive role and therefore promoting and enabling sport participation for young women may be an investment in girl’s education. Title IX remains an important piece of federally sweeping legislation that reflects and informs shifting societal opinions on women’s abilities and their right to play. Since the implementation of Title IX, millions of girls and women have been able to reap the benefits of PA through sport. As women become more empowered through sports as young girls, they increasingly remain active in adulthood and self-select high impact/intensity programs as their activities of choice. Activities such as High Intensity Interval Training (HIIT) including circuit training, P90X™, CrossFit™ and other high intensity programs have experienced rising popularity over the past few years. Though there are many clear benefits of PA in youth and throughout the lifespan, it is important to understand how life-long PA and activity selection impact pelvic floor and skeletal 22 health long term, so that potential windows of vulnerability can be avoided and windows of opportunity utilized. THE HISTORY OF PELVIC FLOOR DISORDERS PFDs, and most notably POP, have plagued women for centuries. While SUI and POP are both considered serious forms of PFDs, there are fewer historically documented accounts of SUI than POP. SUI undoubtedly occurred in historical populations, but mere urinary incontinence was often overlooked due to the severity of symptoms in women with POP (Cundiff, 2004). One of the earliest accounts of POP comes from the Egyptian Papyri of 1835 B.C.E. ‘of a woman whose posterior, belly, and branching of her thighs are painful, say thou as to it, it is the falling of the womb’ (Kahun Papyrus, 1835 BCE; Downing, 2011). During the age of Hippocrates and his pupils, prolapse continued to afflict women; the treatments of this era were entangled with mysticism. Some treatments were logical, others were torturous. The use of fumigation- sweet smells at the head and putrid ones by the uterus to force its retreat upwards was ineffective. In contrast, applying astringents and using a halved pomegranate to hold the uterus in place (the earliest noted form of a pessary) were more successful. Soranus, of the first century C.E., rejected some of these treatment forms. He would cleanse the prolapsed uterus, wrap it in clean linen soaked in astringent, replace it and use a woolen tampon that extended the length and width of the vagina to hold it in place. This treatment form was somewhat effective, and more humane than Hippocrates’ practice of succussion, where the woman was hung upside down by the ankles, bounced, and left inverted for days (Downing, 23 2011). Unfortunately, the understanding and knowledge of female anatomy and gynecology remained obscured in mystery and myth for many centuries (Green, 1983). Medieval concepts reverted greatly back to thoughts of Hippocrates. Some treatments, such as burning the prolapsed uterus with a red hot iron, were particularly barbaric (Downing, 2011). During the Renaissance, the work of artists alongside physicians and anatomists helped propagate the truth of female genital and reproductive anatomy, including a single cavity uterus as opposed to the previously conceptualized multi-horned uterus. By the end of the 16th century, treatments became more rational and civilized. The use of a pessary was the most frequently prescribed remedy for a prolapsed uterus. Historical pessaries of fruit and wool shifted to ovals of brass and waxed cork, primarily devised by French royal surgeon, Ambroise Paré. By the late 1800s materials changed greatly, particularly with the introduction of Charles Goodyear’s patented vulcanized rubber pessary. Pessaries are still prescribed to this day, and were the principal therapy particularly in the late 1800s, although they occasionally caused more problems than they solved. ‘It was said in those years that fortunes were made by two groups of gynecologists: those who inserted pessaries and those who removed them’ (Downing, 2011, p. 2). Though the pessary is still in use, the understanding of the onset and treatment of POP has been continually evolving. Even in the 1800s the potential role of PA and the development of POP were observed. In 1872, W. Whitehead stated in his review of prolapse, ‘the origin of a case of prolapse is invariably connected with some violent emotion or exertion, and is principally found amongst the class who are in the habit of lifting heavy weight, and not amongst the grades of those whose luxurious and indolent habits induce a condition of relaxed fibre’ 24 (Ricci, 1945, p. 282). Another physician, Hugh Hodge explained that many of his patients ‘trace[d] the commencement of their sufferings to straining efforts… a long, fatiguing walk, to running, or jumping, to prolonged or violent dancing, to an effort made in raising weights or carrying burdens, to ascending stairs or heights; indeed to any sudden or powerful contraction of the abdominal muscles and diaphragm’ (Hodge, 1868, p.343). The discrepancy between these two physicians of the 1800s demonstrates how most physicians held different paradigms on the causes of POP. Whitehead attributes the development of POP mostly in working class women who consistently lifted heavy loads, while Hodge considered vigorous physical efforts, most likely completed by upper class women, to be ‘transitory causes’ of prolapse because they started and ended quickly. As noted in the history of women’s PA above, this is accurate; the types of PA that women engaged in during the 1800s varied by class with lower class women laboring in fields or factories and upper class women partaking in activities or sporting outings that were acute and transitory in nature. Physicians of the 19th century also saw clothing as a potential contributor to the development of POP. The corset was very much in fashion at this time, and women would don a corset and lace it tightly in order to obtain the desired lady-like 18” waist (Steele, 2001). It was theorized that corsets displaced internal organs, and would force the pelvic organs to prolapse into and out of the vagina. Similar to physical activity, some physicians saw corsets as transitory causes of POP; once the corset was removed the prolapse would revert to normal. ‘Many of the causes [of POP] there are many of a daily recurrence which can, however, be readily obviated such as all compression of the abdomen by tight dresses, corsets, ligatures, and abdominal supporters’ (Hodge, 1868, p. 25 367). Others proposed that chronic corset use and continually increased intra-abdominal pressure led to the eventual irreversible development of POP (Taliaferro, 1878). There were multiple hypotheses outside of PA about the etiology of POP. From the 1800-1900, POP was a trendy and common topic for graduation theses (Ricci, 1945). POP was believed to be caused by ‘increased weight of the organ, a diminution of strength of the supporting structures, an increased pressure from superincumbent viscera, laceration of the perineum, continually erect posture after childbirth or abortion, muscular exertion, lifting weights and straining at the stool’ (Ricci, 1945, p.270). Interestingly, some of these hypothesized causes of POP are almost identical to theorized contributors today (Wu et al., 2014; Nygaard et al., 2008), though understanding of PFDs is greatly expanded since the 19th century, there remains a need for additional research. The slow rate of advancement in the understanding of the development of prolapse may be partially attributed to an increased focus on its treatment, particularly surgical treatments. In fact, the late 1800s have been called ‘the dark ages of operative furor’ (Speert, 1973, p. 469). Some of the original procedures included surgically removing elongated cervixes; sewing the anterior and posterior walls of the vagina together; trifold repairs of the anterior, posterior vaginal walls, and perineum; sewing the uterus and cervix to the abdominal walls; and a host of other experimental procedures. The first vaginal hysterectomy was completed early in 1861, and was successful enough that the patient was able to present to the New Orleans School of Medicine with her uterus in hand (Ricci, 1945). Abdominal hysterectomies were performed not long after, starting in the late 1880s and early 1890s. Yet, there were many women whose lives were irreparably damaged by surgical attempts to improve an already insufferable condition. 26 Of one patient in 1869, the New York Medical Journal said ‘we have now under our charge a patient operated upon nine years ago by Sims’ method; in a year, the [sutures] had given way, and the [prolapse] returned. Three years ago, she was operated on twice by the Emmet method; in a little more than a year, the bands gave way, and her condition was worse than before, for the vagina was so deformed by the cicatrices [scars] that it became impossible to adjust a pessary’ (Ricci, 1945, p.285). This story of surgical failure and repeat surgeries is not uncommon today; many women who have a surgery to correct a PFD need repeat procedures (Dunn et al., 2014). Admittedly, surgical methods have improved and there is evidence to show that women do enjoy an improved quality of life due to decreased symptoms after surgery (Polin, 2012). Certainly, some of the sufferings of historical women can be attributed to crude or uninformed medical practices, but their stories of discomfort, embarrassment, pain, scarring and recurrent surgery echo the stories of women today. Despite the improvements that have been made, women who are currently struggling with these disorders, and the women of the future who may potentially face a PFD diagnosis deserve to have researchers and physicians continue the search for more effective methods for treatment and prevention. THE HISTORY OF SKELETAL HEALTH AND OSTEOPOROSIS Similar to PFDs, OP affected women (and men) even in ancient times, as far back as the ancient Egyptians. In many ways, OP is much easier to study and estimate in historical populations for a number of reasons. Firstly, the bone tissue affected can be 27 preserved for thousands of years. Assuming skeletal remains can be accessed, bone density, fractures, and other determinants of skeletal health can still be examined today. Secondly, the skeleton is a common bodily component between men and women, and is not directly associated with women’s reproductive capacities. Therefore, historical societies did not seem to hold the same mythical, mystical view of weak bones as they did of falling uteruses, so women may have been more likely to seek treatment for maladies of bone. Thanks to paleopathology, light has been shed upon the skeletal health of historical populations. This section will seek to examine this research and elucidate any potential trends related to PA such that we may be able to draw conclusions from the past that may impact the future. Though current medical providers may feel that OP is a new disease that has only begun to emerge in the 20th and 21st centuries, this simply is untrue, as evidenced by skeletal remains (Stride, Patel & Kingston, 2013). Some skeletal remains are recoverable many millennia after they were deposited, though not all subject material is suitable for study. Bones that are placed directly in dirt may be damaged by acidity, water, temperature, soil-dwelling micro-organisms and other environmental factors. If bones have been broken or worn down they may not be suitable for study because the trabecular (spongey/inner) component will usually deteriorate more quickly than cortical (hard/outer) bone. Over a period of time, the minerals in bone can be leeched into the soil, thus compromising any mineral density examination. The best bones for analysis are those that are dry and uncontaminated by soil. Procuring appropriate samples of bone for study is just half the battle; the methods of analysis to examine these skeletal remains must be current and used correctly 28 to ensure diagnostic precision and reliability (Stride, Patel & Kingston, 2013). The methods of choice include dual-energy X-ray (DEXA) scans and pQCT scans, which are the preferred scan for diagnosing OP in current patient populations. DEXA scans use dual X-ray beams with different frequencies: one frequency (low) will be absorbed by soft tissues, then by subtracting the first frequency out, the second (high) frequency can provide information relative to bone. pQCT is able to provide supplemental data like volumetric bone density and strain index, a measure for bone strength (Engelke et al., 2008). Bone histology, involving the cutting of bone, is very accurate, although it is not often appropriate with ancient skeletons. Between these various methodologies, DEXA is by far the most popularly used in paleopathology. Since DEXA scans are normally performed on living people, they are normalized to the tissues that surround bone like muscle, fat, and skin. When isolated, historical bones are examined, they have to be put in ‘soft tissue equivalent’ like water or rice. This can make comparisons between live and historic populations difficult, which is why many researchers prefer to make comparisons between skeletal remains that come from the same time period and geographic region (Stride, Patel & Kingston, 2013). Some researchers caution that comparing within one grouping of skeletal remains can paint a very narrow picture of skeletal health, so it is important to make comparisons across different populations and to incorporate any health records of the time. There will undoubtedly be further advancements in our ability to determine BMD in archeological samples, but the evidence for now is presented below. The skeleton of a Bronze Aged 4,000 year old female, estimated to be 45 years old at the age of death, was exhumed in Austria. In comparison to 14 other women who were approximately the same age and from the same grave, this subject had notably 29 lower bone mineral density at the hip, with 0.831gm/cm² compared to 0.981 gm/cm² among the others. This evidence suggests that there were some women who had lower bone density than others, although this subjects’ BMD falls within 1 standard deviation of the other study subjects, meaning she would be diagnosed with osteopenia rather than OP, which requires a BMD of greater than 2.5 standard deviations from the population average. Interestingly, all 15 women examined had lower BMD than five men from the same grave who had an average BMD of 1.195 gm/cm². This finding is consistent with current skeletal health trends, in which men tend to have greater BMD than women (Eagle, Frigo & Lang, 1995; Stride, Patel & Kingston, 2013). As is true today, both women and men appear to lose BMD with age. Turkish skeletons from the Neolithic age were examined, and both older men and women were shown to experience diminished cortical thickness when compared to their younger counterparts (Agarwal et al., 2011). Austrian Bronze Age skeletons were examined, comparing a group of those aged 30-40 years with a group of 40-60 years; the 40-60 year old group had large drop offs in trabecular bone quantity and quality (Kneissel, Boyde & Hahan, 1994). Women seem to lose cortical thickness at a faster rate than their male counterparts. Femoral cortical thickness was examined among Portuguese Neolithic bones from approximately 4,700 BCE and the cortical thickness of older women in particular, appeared greatly deteriorated (Jackes & Lubell, 1992). The examination of Egyptian and Nubian bones helps to illuminate the average age when bone began to decline. Egyptian mummies from Italian museums that were very well preserved were examined. Out of 33 total mummies, three female and one male specimens were found to have OP. All of the subjects were over age 35, and considering 30 the average life expectancy for Egypt during that time was 35-45 years, these skeletons would have likely been from some of the oldest living members of society (Giuffra et al., 2009 ). Significant bone loss by the third decade of life is also supported in an examination of well-kept Nubian bones (Armelagos et al., 1972). In more recent times, an examination of the femoral necks of Portuguese skeletons from the 1800s revealed that women above 80 years and older had a mean BMD of 0.468g/cm², which is much lower in comparison to the 0.821g/cm² mean BMD of the 20-29 year old group (Albuquerque, 2011). Among skeletons from an 18th-19th century London graveyard, bone density of females (0.332 g/cm²) was found to be significantly less than the bone density of males. Additionally, ‘there was a significant, negative relationship with bone density and age in females, but not males’ (Brickley & Waldron, 1998, p. 279). While skeletal remains are helpful in informing our understanding of bone health and OP in historical populations, there are many factors that may contribute to the promotion or deterioration of bone health, including PA, nutrition, reproductive hormone status, sunlight exposure (Vitamin D), longevity, parity and lactation. Therefore, it can be difficult to attribute the occurrence (or lack thereof) of OP to one factor in any historical population. It is important to keep skeletal health in context of its nebulous causes. Even today, if a woman develops OP, often a single line cannot be drawn to one contributing factor like a lack of PA alone; usually, the etiology includes a combination of many factors. One study of ancient Egyptian skeletal remains from the Giza Necropolis of the Old Kingdom (2687-2191 BCE) revealed that there were differences in trabecular bone 31 and osteoporotic cases based on both sex and social status. Working class men were more likely to have OP compared to upper class men, whereas lower class women were less likely to have OP compared to higher class women (Zaki, 2008). The authors postulated that low class men may have developed OP on a more frequent basis as a result of poorer nutrition in comparison to the high class men. Although high class ancient Egyptian women likely shared the same nutrient dense diets of their high class male counterparts, they were more likely to develop OP in comparison to lower class females. This demonstrates that nutrition alone was not the deciding factor of skeletal health. The authors postulated that high class women were likely more sedentary than their working, lower class counterparts, and therefore PA (or lack thereof) may have played a greater modifiable role in the development of OP for women. All things considered, both high and low class women experienced faster rates of bone loss and a higher prevalence of OP than males of either social status (Zaki, 2008). This evidence supports the consistent finding of women losing bone at greater rates than men; it also supports the idea that for ancient Egyptian women, a lack of PA may have been more deleterious than poor nutrition to skeletal health. Interestingly, levels of PA through manual, household, occupational labor, and transportation were probably higher for most working class women throughout history than they are today, though women today may get more intentional exercise. Women completed tasks that required substantial amounts of physical effort and exertion such as washing clothes, carrying burdens, working agricultural fields, and walking as a form of transportation. Many of these activities have since been replaced by labor saving devices such as washing machines, tractors and cars, so it is possible that women of today would 32 be at a higher risk of lower bone mineral density as compared to those from centuries BCE up until the Victorian Era (Stride, Patel & Kingston, 2013). Another factor of osteogenesis related to manual labor is sunlight-- a critical component of Vitamin D synthesis which enables the absorption of calcium from the gut tube so it can be used in the ossification of bone. Women who labored outside, such as the ancient Egyptians, did not have access to the sunscreens of today and were probably more likely to have much higher levels of Vitamin D, which may have also contributed to higher bone density in working class women. Despite these two factors, skeletal remains indicate that ‘past populations probably achieved a lower peak bone density than today, in spite of greater activity and probably greater exposure to sunlight and higher Vitamin D levels (Stride, Patel & Kingston, 2013, p.258). Lower peak bone mass could have been due to issues of nutritional deficits in the minerals, such as calcium, needed to maintain bone health. Other factors that influence osteogenesis and OP are age of menarche, pregnancy, parity, lactation and menopause. Pregnancy, parity levels, and menopause are also potential contributors to the development of pelvic floor dysfunctions, thus parity and PA are mutual risk factors relevant to the health outcomes considered in this thesis. Later onset of menarche (17-19 years) compared to an earlier age of menarche (11-13 years) has been shown as risk factor in developing OP because it diminishes the time period in which hormones are favorable to bone health (Li and Zhu, 2005). Similarly, early onset of menopause (40 years) compared to later onset of menopause (50+years) increases the risk for OP development due to decreased duration of hormonal favorability for bone maintenance. Documentation for the age of menopause onset in historical populations is not as strong as data for onset of menarche, but there is some evidence, like in the 33 writings of Aristotle, that onset of menopause was earlier (40 years) than the current average (51 years) (Stride, Patel & Kingston, 2013). Onset of menopause plays a distinct role in the accelerated rate of bone resorption due to a change in the hormonal milieu. Post-menopausal women, both ancient and modern, have been shown to lose bone mineral at much faster rates than men of the same age. Age of menarche also appears to have changed over the past few centuries. The average age of menarche in US women was 17 years in 1830, which declined to 13 years in 1980 (Evers & Heineman, 1990). Shifting patterns in menstrual cycles and fertility may explain a few historical and current trends in bone health. A late age of menarche in combination with an early onset of menopause may explain why ancient Egyptian, Austrian, and Nubian skeletons would have already shown signs of osteoporosis in their 30s and 40s (Stride, Patel & Kingston, 2013; Armelagos et al., 1972; Giuffra et al.,2009). Current younger average age of menarche with older age of menopause could be partially responsible for higher peak bone mass found in modern populations compared to historical populations. Therefore, in this case, compressed reproductive capacity may have played a large role on the development of OP in younger female skeletons throughout history. Numerous authors have proposed that pregnancy, number of pregnancies, and duration of lactation can affect bone mineral accrual and loss. A developing fetus requires approximately 30g of calcium for initial skeletal formation (Stride, Patel & Kingston, 2013). This equates to about ‘2-3% of the maternal calcium transferred to the fetus’ for a total decrease in maternal BMD of 3% during pregnancy (Salari & Abdolahi, 2014, p. 136). There is also maternal loss of calcium during lactation, with 300-400mg lost daily 34 through breast milk. To reestablish bone mineral stability following pregnancy, there are a number of counter-regulatory pathways that help to restore calcium and bone density levels to pre-pregnancy level; these mechanisms work very effectively, essentially reversing all calcium and BMD loss. It would appear that the data do not support that pregnancy or lactation causes permanent bone loss (Alderman et al., 1986; Salari & Abdolahi, 2014). One may wonder if the restoration of mineral varies with multiple pregnancies. The research shows that multi-parity has a protective factor for bone mineral density. In studies conducted with modern women, a higher parity level (up to five pregnancies) appears to improve bone mineral density. Arguably, this increase in BMD could be the result of hormonal changes and counter-regulatory pathways, or it may be that contemporary women who raise more children may lead more active lifestyles simply in the form of childcare and play, thus improving their bone mineral density. The one form of parity that seems to impact bone mineral density and the development of OP is the age of first pregnancy. If initial pregnancy occurs during adolescence, there can be permanent reductions in BMD. Among Korean women examined for post-menopausal OP, those who had teenage pregnancies were 2.2 times more likely to be diagnosed with OP compared with mothers who got pregnant in their twenties or thirties (Cho, 2012). Similarly, other research has shown decreased cortical density in the wrist and decreased bone mineral content in teen mothers compared to older mothers (Ward et al., 2009). Considering short average lifespans in historical populations, teen pregnancies were extremely common and may have played a large role in the early development of OP in some of the skeletal remains studied. 35 As these studies of skeletal remains demonstrate, weak bones and subsequent fractures have presented problems for millennia. It was not until the 19th century that the mechanisms for OP were understood. The concept of bone remodeling, constant osteogenesis, and resorption was discovered by the Scotsman John Hunter (1728-93). Later medical professionals, like Sir Astley Cooper (1768-1841), began to notice the high hazard of fractures in old age as a consequence of lower bone density. The idea of ‘porous’ bone and the term OP were coined in the 1820-30s by Jean Lobstein of France. Though Lobstein’s perception and definition of OP is the same as it is today, there were many physicians through the mid-19th century who would incorrectly use this term to describe other diseases (Stride, Patel & Kingston, 2013). It was not until the work of Fuller Albright (1900-1969) that some key components of OP, such as decreased osteoblasts, were learned. Albright astutely observed the main bones affected were in the spine, pelvis and long bones; he also noted an increased prevalence in older postmenopausal women, particularly those who underwent menopause early. Recognizing menopause as a contributing factor to bone loss, Albright prescribed estrogen, which was one of the first effective treatments for stopping bone loss. In addition to menopause, Albright associated OP with ‘senescence and disuse,’ one of the first hints that lack of PA plays a role in the development of OP (Stride, Patel and Kingston, 2013, p. 255). Other discoveries of the 1960s, like bisphosphonates by Herbert Andre Fleisch (1933-2007), helped to transform the treatments of OP. Currently, a variety of research is being conducted at the cellular level to determine physiological mechanisms and potential pharmaceuticals to halt or reverse the onset of OP. The invention of devices to detect bone density has also been exceptionally helpful in diagnosing low bone mass and 36 OP prior to fracture. The understanding of bone health and OP has expanded greatly since ancient times, particularly with regards to PA. Some of the research on PA and bone health is reviewed in later sections. Ultimately, these historical accounts of low bone mass help health professionals and public health practitioners to understand how previous trends juxtapose with current ones, and prepare us for the OP epidemic that is coming. PERSPECTIVES OF HISTORICAL PA, PFDS AND OP Looking at the history of women’s PA, incidence of PFDs and OP all together allows for some conclusions to be drawn on the interactions between the three. Understanding that PFDs and OP have been health problems for millennia demonstrates they are not new conditions, and provides insights into the anticipated high prevalence within our aging society. An examination of women’s patterns of PA, women of historical populations from ancient times up until about 200 years ago, did not have intentional exercise routines, nor did they often engage in organized sport. However, women of lower socio-economic status typically had high levels of PA through means of strenuous household tasks, manual labor, and active forms of transportation. Some studies have indicated that these working class women had higher levels of bone mineral density than upper class women who didn’t perform manual labor (Zaki et al., 2008). In the opinions of some 19th century physicians, this chronic manual labor was one of the main contributors to pelvic floor disorders like POP. Other physicians felt that individual bouts of PA, like walking or 37 dancing, were acute and ‘transitory’ causes of PFDs, that once halted would reverse induced symptoms (Ricci, 1945, p. 282; Hodge, 1868, p.34) Gains in length of average life-span, rather than activity levels, may play a larger role in the development of PFDs and OP. During the times of ancient Egyptians, the average lifespan was only 35-45 years old; by comparison, life expectancy at birth for women in the United States is now 81 years (Arias, 2015). The lifetime risk of developing both PFDs and OP increases with age. In the case of OP, bone density has been seen to decrease dramatically with falls in estrogen that accompany menopause, but typically stabilizes after a few years. While the women of Egypt likely experienced menopause earlier than women do now, they may have lived ten or fewer years after onset, if that. Women today live for a number of decades after menopause, and are have a much higher chance of experiencing falls and fractures due to OP during that time (Surgeon General’s Report, 2015). Prevalence of PFDs also increases with age, and increased longevity may play a key role in their development. There are many historic accounts of POP and other ailments of the female reproductive system, but anecdotal reports and historical prevalence of POP seems slightly lower than modern prevalence rates. This discrepancy may be due to underreporting but may also be due to shorter average lifespans among historical populations compared to modern ones. Women from past populations didn’t live long enough to develop PFDs that would have occurred if longevity allowed. The increased focus on surgical treatment of POP during the 19th century may indicate the proportion of PFDs grew with paralleled increases in life expectancy during this time. 38 High fertility rates may have also played a role in the development of PFDs and OP in women of history. Pre-industrial societies like those of the historic populations examined in this paper, experienced high mortality rates and compensatory high fertility rates. With one in every two or three infants dying, parity was high in order to sustain ancient populations; for the Egyptians women on average had four to six pregnancies, but some had up to 10 or 15’ (Parsons, 2011; Stride, Patel & Kingston, 2013). While multiple pregnancies have been proposed to contribute to loss of bone mineral density, the evidence does not support this. While multi-parity itself does not affect BMD, age of first pregnancy- notably teenage pregnancies- may permanently reduce BMD (Cho, 2012). High parity rates are also a risk factor for developing PFDs. Interestingly, older age during pregnancy (35 years+) is associated with a greater risk of developing PFDs due to a lack of elasticity of tissue. However, another risk factor for PFDs is long, complicated and difficult labor, so it is logical that teenage mothers without fully developed pelvises may have been at a greater risk for difficult labors. Looking at historical versus modern trends, women didn’t engage in exercise as much as they do now, but they were more habitually active. Women have developed PFDs and OP, seemingly since the beginning of time, which likely means these conditions will never be completely eradicated. Some of the shifts from antiquity to modernity are outlined in the table below. In the next section, current research that demonstrates the (potential) effects of PA, exercise and sport on pelvic floor and skeletal health are discussed. 39 Physical Historical Modern  More PA through labor, transportation   Less PA overall More exercise and sport    Higher Parity Lower Average BMI Increased Intra-Abdominal Pressure due to clothing (corsets) Smaller Reproductive Window (older menarche/younger menopause) Lower Peak BMD More Teenage Pregnancies   Lower Parity Greater numbers of deliveries by Cesarean Section Higher Average BMI Longer Reproductive Window Higher Peak BMD Fewer Teenage Pregnancies Activity Pelvic Floor Health Skeletal Health        THE IMPACT OF PA ON PELVIC FLOOR HEALTH Despite the long history and current ubiquity of PFDs, there remains limited research on the causes of PFDs, although PA may be a potentially modifiable risk factor in their development. Since the mid-1990s, the body of research on the effects of PA on pelvic floor health has grown, but many gaps persist. Nygaard and Shaw point out in their review paper that population based studies are needed and, ideally, randomized control trials would be conducted. Since the true impact of PA on the pelvic floor is unknown, it may be unethical to randomize women into PA and non-PA groups. In particular, it would be unethical because PA has been demonstrated to have numerous other positive effects on health that would be 40 compromised if a participant was randomized to non-PA group (Nygaard & Shaw, 2016). Further, if certain types of PA are detrimental to the pelvic floor, it would be equally unethical to randomize women to some types of PA. This section will examine the existing body of literature, including several small cross-sectional studies and will hopefully elucidate general trends in the effect of PA dose and its mitigation or contribution to the development of UI and POP. There are two contrasting theories on the effects of PA on pelvic floor dysfunction. The first postulates that increased PA causes frequent engagement of the pelvic floor muscles, and thus trains and strengthens these muscles, decreasing the risk of PFDs such as POP and SUI. The opposing view is that PA may actually apply excessive strain and stretch of pelvic floor muscles, thereby increasing the risk of PFDs (Bø, 2014). Athletic endeavors that involve high force impacts such as repetitive jumping, straining and heavy lifting are theorized to be potential contributors to pelvic floor dysfunction. While most historical accounts of PFDs focused on POP rather than SUI, the majority of modern research examines the impact of PA on SUI not POP. One landmark prospective cohort study examined the effects of high impact summer paratrooper training in nulliparous female cadets on the development of both POP and SUI. Paratroopers are subjected to two moments of force that have been theorized to impact the pelvic floor: when the parachute opens, and when the paratrooper lands. The two cohorts examined included those in paratrooper training which includes these uniquely high impact forces, and controls in other strenuous but not high impact summer training such as jungle or survival training. Participants were given questions and examined using POP-Q before and after the six week training. For paratroopers, training featured 41 ‘physical conditioning, tower training, and five live jumps’ (Larsen & Yavorek, 2007, p. 769). Following the training, participants repeated the questionnaire and POP-Q exam. The women who attended the paratrooper training were ‘significantly more likely to develop Stage II prolapse and were also significantly more likely to have worsening in their pelvic support regardless of initial prolapse stage’ compared to controls who participated in other forms of training (Larsen & Yavorek, 2007, p. 769). A number of participants complained of UI, however UI was not found to be associated with paratrooper training. The findings of this study indicate that repetitive, high impact forces such as those experienced by paratroopers as they jump from planes, may significantly affect the pelvic floor and contribute to pelvic support defects (Larsen & Yavorek, 2007). While this evidence indicates high impact activity may have a deleterious effect, most women will not choose paratrooping as their main form of PA or exercise therefore it is difficult to generalize these results. There is a great need for further research to examine the effects of PA on the development of POP; the remainder of this section focuses on the research that evaluates PA on SUI. Some research that supports the theory of PA leading to excessive stress and strain of the pelvic floor, indicate that female athletes, especially at elite levels struggle with SUI at greater rates than lower level athletes or other generally physically active women. Athletes of high impact sports such as competitive trampoline jumping, gymnastics, volleyball, basketball, soccer, and long distance running may be particularly affected. Among trampoline jumping, a specialized form of gymnastics, high prevalence rates of SUI have been documented. In nulliparous elite Swedish trampolinists, nearly 42 80% of 35 surveyed reported leaking urine during training or competition; urine leakage was confirmed using pads that were weighed before and after a trampoline session, with an average of 28g or urine lost (Eliasson, et al., 2002). Similarly, among nulliparous Portuguese trampolinists, 72% experienced urinary incontinence during trampoline sessions. The athletes sampled only noted urinary incontinence after their engagement in trampoline jumping began, indicating that SUI was not present before trampoline training. It was further demonstrated that severity of incontinence was correlated with duration, frequency, and volume of training. Athlete ranking was also correlated with incontinence, with higher ranked athletes experiencing more instances and greater volumes of self-reported urine leakage (Da Roza, et al., 2014). Gymnasts also report relatively high rates of SUI. Among elite Danish athletes, studied by Thyssen et al., gymnasts reported the highest rates of SUI (56%) compared to participants of other activities such as ballet (42%) and badminton (31%) (Thyssen et al., 2002). In a study of nulliparous, varsity-level University athletes, Nygaard found 67% of gymnasts reported incontinence compared with 0% of golfers (Nygaard, 1994). Of all the athletes surveyed, ‘7% noted incontinence during only sports. All but one of the women with incontinence exclusively during sports were gymnasts’ (Nygaard, 1994, p. 183). Gymnasts, both of the trampoline and general variety, appear to experience great impact upon landing, and thus may have concomitant changes in intra-abdominal pressure that could overwhelm continence mechanisms leading to high rates of SUI. Other sports that require repetitive jumping such as basketball and volleyball have also been indicated as potential contributors to SUI. In the study of Danish elite athletes, 30% of volleyball players and 17% of basketball players reported urine leakage during 43 their activities (Thyssen et al., 2002). However, prevalence rates for both basketball and volleyball do not appear consistent across multiple studies. Nygaard et al. found that a much higher percentage of basketball players (66%) and a much lower proportion of volleyball players (9%) suffered from UI. By comparison, Schettino et al. found a much higher prevalence rate of nearly 65.7% among volleyball players. No studies have looked at a large population of basketball or volleyball players broken down by parity, age, competition level, player position, and duration/volume of training to determine if these variances in prevalence rates may be due to any of these confounding factors. Soccer, an increasingly popular sport among girls and young women, has also been studied in terms of SUI. Amongst 38 Portuguese indoor soccer players aged 18-45 who had been playing soccer at least one year, 50% admitted at least one episode of urinary incontinence. One study examined UI symptoms using urine pads in adolescent, amateur level soccer players and compared them to an age matched control group. The researchers found that ‘the athletes displayed 62.8% positivity on the pad test, whereas the control group exhibited 25% positivity’ (Fernandez et al., 2014). Studies like those conducted by Fernandez et al. on active adolescent girls highlight a number of important considerations for women’s pelvic floor health, namely, periods of vulnerability. If girls as young as 12 experience symptoms of pelvic floor dysfunction, does that indicate adolescence is a particularly vulnerable period for the development of such disorders? Another consideration involves issues relating to duration and recovery. If a young girl experiences pelvic floor dysfunction at a young age, will the condition be chronic and permanent, or is it something she will simply 44 outgrow? If the condition is persistent in nature, is there something that she can do to reverse or mitigate the development of the condition across her lifespan? Interestingly, multiple studies indicate incontinence may happen more often during training than competition. Of 239 Danish elite athletes who experienced incontinence studied by Thyssen et al., the majority experience leakage during training (95.2%) compared to competition (51.2%) (Thyssen et al., 2002). Similarly, Nygaard et al. found that among nulliparous, varsity-level University athletes who experienced SUI, leakage was more common during training sessions-- 16% compared to 14% during competition. Increased incontinence during training rather than competition is important because ‘training’ for athletes in some cases is more reflective of the types of exercise and PA that typical women may engage in. Frequency of incontinent episodes during training indicates there may be differences in training vs. competition hydrating or voiding habits. It is also possible that variable levels of catecholamines during competition could affect receptors in the urethra, thus altering rates of involuntary incontinence (Thyssen et al., 2002). The perceived causes of incontinent episodes in athletic women vary between studies. Jácome et al. found ‘situations and activities most likely to induce urine loss were an urgent need to go to the bathroom (43.2%), coughing (38.6%), practicing sport (36.4%), sneezing (31.8%), and laughing (31.8%) (Jácome et al., 2011). Comparatively, across the 291 Danish athletes in 8 different sports, the ‘activity most likely to provoke leakage was jumping’ (Thyssen et al., 2002). Though women cited different stimuli for urine loss, reactions are fairly similar. For many women, UI is a ‘social and/or hygienic problem’ as per older definitions of 45 SUI. Women report urinary incontinence as frustrating, embarrassing, and inhibiting of athletic/occupational performance. Women often engage in coping strategies to prevent or mitigate their UI, including reduced fluid intake, preventive voiding, wearing absorbent pads or panty shields, reduction or cessation of activity that causes UI, or, in extreme cases, surgery (Brown & Miller, 2001). Some approaches, such as wearing panty liners or scheduled voiding/voiding prior to activity, may be time-consuming and cumbersome, but they in general do not have negative impacts on other aspects of physical health. On the other hand, reduction of fluid intake may be harmful acutely, especially leading up to strenuous PA or play when hydration is a key component of adequate sports nutrition and thermoregulation. Quitting PA to avoid incontinence impacts quality of research as well as the health of (former) participants. Studies examining pelvic floor dysfunction in active women may not accurately reflect the true extent of the problem because women who experience the worst symptoms may have already terminated activity. In their longitudinal study of Australian women, Brown and Miller found ‘the data are highly suggestive that leaking urine may be a barrier to PA, especially among mid-age women’ (Brown & Miller, 2001, p. 373). Reduction of PA is a troubling coping mechanism because it may negatively affect other aspects of a woman’s health. PA has been clearly demonstrated to improve blood pressure, blood lipids, maintenance of body composition, bone health and various mental health states. It is also ironic because PA and physical therapy are typically one of the first courses of treatment for UI and pelvic floor dysfunction, so if women stop PA to prevent incontinent episodes but are then asked to 46 engage in PA as a treatment, it may influence her adherence to an exercise or treatment program. It is important to note that many of the strategies employed by women to limit incontinent episodes are usually self-decided without the advice of a health care provider. In fact, many women do not discuss pelvic floor dysfunction with anyone-- friend, family, or physician. Many women may not recognize PFDs as diseases, and may even perceive them to be ‘normal’ consequences of activity, childbirth or aging. Among incontinent women seeking care in one study, the ‘main reasons for not seeking medical advice included: feeling embarrassed, not knowing it was remedial, perceiving SUI to be a normal consequence of childbirth, and having to attend to the needs of the family’ (Perera et al., 2014, p. 1). This may also relate to lack of knowledge about the pelvic floor; most women are unaware that there are connective tissue/muscular supports that surround pelvic openings commonly affected by PFDs. It is also reflective of societal norms regarding women’s genitalia. Many women’s health issues remain taboo, to the point that women only admit to having a problem when their daughters are diagnosed, too. There is room to embrace and recognize PFDs as serious conditions worthy of attention. THE IMPACT OF PA ON SKELETAL HEALTH Unlike pelvic floor health, skeletal health is not shrouded in stigma and has thus received a lot more attention and research funding as relates to PA. As mentioned above, OP is the result of insufficient accretion of bone mass prior to full maturation of the 47 skeleton and/or the copious bone loss after skeletal maturity. The following research demonstrates the benefits of PA during youth to build bone and to mitigate bone loss in adulthood. For young girls, childhood and adolescence are windows of opportunity for bone growth. PA during youth is important for two reasons. To begin, PA has been shown to be more osteogenic prior to and during puberty (Szadek & Schrarer, 2013). About a quarter of peak bone mass for girls accumulated during the adolescent period and a total of 40% of bone mass accrues during adolescence (Bachrach & Sills, 2011; Szadek & Schrarer, 2013; Staurowsky et al., 2015). Second, many lifestyle behaviors including PA are cultivated in youth; if young women can implement a habit of PA that they maintain throughout their lifespan, they will be set up to build bones while they are young and maintain them as they age. The accrual of bone mass through PA in youth has been well demonstrated, although activity type can by highly influential. Activities that mechanically load the bones in multiple sites such as gymnastics, tennis, soccer, and running and are more likely to improve bone mineral density (BMD) compared to low impact activities such a swimming and cycling (Hind, 2007; Bieleman et al., 2014; Saravi & Sayegh, 2013; Meyer et al., 2011; Staurowsky et al., 2015). A number of studies have been conducted on gymnastics, which loads bones in multiple sites and experience high ground reaction forces. Even in very young 4-10 year old girls who partake in non-competitive gymnastics, improvements can be seen in bone health. Erlandson et al. found that gymnasts had 3% more total body and 7% more femoral neck BMD than children in other recreational sports after 4 years of participation 48 (Erlandson, 2011). These findings suggest that bone mineral accrual from high impact loading can be beneficial, starting even at a young age. Female gymnasts had 21% more bone mass compared to girls of the same age who were non-gymnasts (Ward et al., 2005). Even after girls quit gymnastics, there are residual benefits on BMD. Kudlac et al. longitudinally examined 10 collegiate gymnasts compared with nine non-athletic college aged women examining pre- and post-retirement bone density. DEXA scans during the last year of competition for gymnastics participants showed significantly higher BMD at multiple sites including the femoral neck, Ward’s triangle, the greater trochanter and the whole body. When follow up was conducted with participants on average four years after the retirement from competition, it was found that gymnasts still had significantly greater BMD than the controls. It should be noted that both gymnasts and controls lost bone during this time, but the gymnasts’ BMD declined a lesser rate-- .72% compared to 1.9% per year (Kudlac et al., 2004). This finding is particularly significant because it lends evidence to the theory that PA in youth has protective factors for skeletal health throughout the lifespan, essentially helping to build the ‘cushion’ of bone that can be lost after skeletal maturity. The authors did note, however, that alterations in BMD were load-site specific, rather than skeleton wide. The finding of site-specific bone mineral accrual is consistent across other research and study populations, not just gymnasts. In one randomized control trial, premenopausal participants were assigned to a six month exercise intervention at varying frequencies (zero, two, four, or seven days per week) that featured multi-directional hopping on just one randomly selected leg. Those who were assigned to the daily hopping intervention experienced a 2% growth in femoral neck BMD compared to 49 control leg, although growth results were not significant for those who exercised only two or four days per week. The two other measured hip sites, lower femoral neck and trochanter, did not experience significant BMD changes across the different exercise frequencies. Though benefits were greatest for those assigned to daily exercise, there were modest improvements across exercise intervention frequency in BMD for the hopping leg compared to the non-hopping leg (Bailey and Brooke-Wavell, 2010). This indicates that hopping or jumping using both legs may be beneficial in increasing BMD; it is noteworthy that this intervention featured only jumping, an exercise that can affordably and easily integrated into someone’s routine within the comfort of their own home with the potential to diminish the risk of OP. The skeletal benefit of general, habitual PA is demonstrable. Among participants in a five-year prospective study, those participants who increased their level of PA had associated increases in BMD, particularly at the hip for female participants (Langsetmo et al., 2011). Participants were not assigned to an exercise intervention, which lends itself to bias, but participants engaged in myriad activities, which lends to the body of research that indicates an increase in PA through various activities may benefit BMD. In an examination of adult pre-menopausal women who were either sedentary, regular exercisers, or members of a federal sport team, level of PA or years of PA were both positively correlated with BMD. However, the members of the federal sports group had the most significant differences compared to the sedentary and regular exercisers in BMD (Saravi & Sayegh, 2013). Thus, the authors posit that PA above and beyond those of the maintenance exercise group/current moderate PA recommendations is beneficial for bone health (Saravi & Sayegh, 2013). 50 One recurring theme in PA/skeletal health research generally states that more activity means more bone. The one caveat to this is found in the form of the female athlete triad. The female athlete triad is a condition made up of three concurrent conditions: low energy availability, amenorrhea [lack of a menstrual period], and low bone mineral density. It is possible that a woman may experience each of these individually, but for female athletes in particular a lack of calories to support the level of energy expended through PA and sport can be the beginnings of female athlete triad symptoms (Manore, Kam & Loucks, 2007). Sometimes unintentionally, or sometimes through purposeful changes in diet (often as a result of disordered eating), a woman will fail to get enough calories. This low energy availability can lead to menstrual irregularities; if complete amenorrhea occurs for long durations of time, it can result in low levels of estrogen known as hypoestrogenemia. Hypoestrogenemia works synergistically with low energy availability to negatively affect bone health, contributing to bone loss, and in the most severe cases, inducing OP. While PA and sport participation offers many potential benefits to female participants usually including increased BMD, the female athlete triad is one of the few things that represents a potential threat to the health of women, in this case, the extreme lack of calories in combination with activity an begin the etiology for this disease (Staurowsky et al., 2015). While still much higher than should be acceptable, the prevalence of the female athlete triad among elite athletes is only about 4%, so the majority of female athletes are most likely deriving bone mineral accrual benefits from PA and sport (Sundgot-Borgen & Torstveit, 2004). However, the health consequences on both a short term and long term basis can be very serious. For fitness professionals, coaches, and health practitioners, it is important to be wary of the 51 signs and symptoms of the female athlete triad so that bones are built up through PA instead of torn down. PELVIC FLOOR VS. SKELETAL HEALTH: ARE THEY AT ODDS? From the research presented above, the relationship between PA and pelvic floor integrity is a bit muddy. Some research shows that women are more likely to experience symptoms of urinary incontinence during high impact activities, though most studies have been conducted on highly competitive athletes who are engaging in activities beyond the average woman’s wildest exercise ambitions. Other evidence suggests that moderate PA, like walking, a more approachable activity for the average woman, is associated with lower SUI symptoms (Danforth et al., 2007). In fact, PA and physical therapy (PT) make up the first courses of treatment upon diagnosis with PFDs, which indicates their potential effectiveness in alleviating symptoms. When it comes to bone health, the benefits of loaded/high impact PA has been well demonstrated for bone growth and maintenance. Research has shown these trends hold true for young, adolescent, adult, and geriatric female populations, with greatest PA benefits seen prior to skeletal maturity at age 30. Although in excessive quantities, poor nutrition in combination with over-exercise can compromise bone health in the form of the female athlete triad. High impact activity is one of the best things women can do to build and preserve bone, yet high impact activity appears to potentially increase the risk for developing PFDs. This begs the question, are the PA means to achieve pelvic floor and skeletal 52 health at odds? Are women in a situation that forces them to decide whether they value their bones or their pelvic floor more? More research needs to be done to say conclusively, but women are most likely safe to engage in moderate PA sufficient to load bones and while upholding pelvic floor integrity. In a recent study, Middlekauff and colleagues compared two groups of nulliparous, healthy, young (mean age=24.77± 4.3) women. One group participated in a strenuous high intensity/impact program at least 3 times a week for six months; the other group participated in nonstrenuous exercise. Measures of pelvic floor support and strength were examined immediately prior to and after a 20 minute bout of exercise normal for each group: the strenuous bout featured weighted and body weight exercises, the non-strenuous featured a self-paced walk. It was found ‘vaginal support and vaginal resting pressure decreased slightly [immediately following exercise]’ but the measurements taken before exercise did not reveal any significant differences between the two groups, and thus indicates that there are neither favorable nor unfavorable effects of chronic strenuous exercise on pelvic floor strength and support (Middlekauff et al., 2016, p. 1.e1). Some women may learn about or be diagnosed with OP or a PFD and be anxious of engaging in PA for fear of making their condition worse. While a fearful response is natural, in this case of PFDs and OP it may be a bit reactionary and a disengagement from PA may actually worsen symptoms or hasten development of the condition. That being said, the best kind of exercise is the exercise that one will actually do and enjoy, so it is important for women to select a form of exercise they enjoy rather than dread. 53 FOR HEALTH EDUCATORS & FITNESS PROFESSIONALS To conclude this thesis, there are a few take away points for fitness professionals, health educators and clinicians. It is important that professionals at every level are familiar with these conditions, especially because they will likely have more and more clients/patients who are faced with OP and/or PFDs. The population of the United States is aging rapidly. It is projected that by 2050 one in three women could have a PFD. Currently 30% of post-menopausal women in the US already have OP, and that number is projected to increase. Therefore, health professionals need to be cognizant when working with older women; the chances they have at least one of these disorders are high. Before recommending or designing an exercise intervention, a conversation with the patient/client to ascertain any symptoms, and then implementing a program that does not aggravate those symptoms is key. When working with an adolescent population, physicians should counsel on appropriate forms of birth control to prevent teenage pregnancy and the resultant longterm decreases in BMD. Fitness professionals working with younger (<30years) women should work to implement exercises that will spur bone growth so as to build a cushion prior to skeletal maturity. When working with currently or recently pregnant women, fitness professionals should be aware that numerous changes and strains are placed on the pelvic floor as a result during this time, and it may be a window of vulnerability for developing future PFDs, especially as relates to PA. A physician should be consulted prior to implementing any new exercise programs. 54 Further research needs to be done on a longitudinal scale to more fully determine the long term health consequences of high impact PA on pelvic floor and skeletal health. In the meantime, knowing the numerous other benefits of PA/exercise/sport, women should be encouraged to find an activity routine they find enjoyable and to which they can adhere. 55 ACKNOWLEDGEMENTS First and foremost, I would like to acknowledge my wonderful parents, Tracy and Richard Lee, who have been amazing examples of positivity and perseverance to me. Without their love and support I would have never been able to make it through college, let alone write this thesis. I would also like to thank my wonderful fiancé, Brian Park, who has helped keep me sane and shown me more patience and love than I deserve. A huge ‘danke shoen’ to my dear friend and editor, Kya Palomaki, who has been invaluable through this process; not only is she my cheerleader, but she has saved all of you readers from an enormous amount of unnecessary punctuation. Of course, a shout out to my friends and roommates, who have endured countless dinner time musings on the pelvic floor. Finally, to my academic mentors, thank you from the bottom of my heart. Dr. Maria Newton, thank you for always being there to talk, or really just listen. To Dr. Shaw, the truly amazing woman who is my thesis advisor/role model, thank you for taking me under your wing since my freshman year. 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