| Description |
In 2012 over 27 million Americans were suffering from Type II Diabetes (T2DM), which cost the U.S. $245 billion dollars in health care costs. Luckily, lifestyle changes and exercise can slow or prevent development of the disease. The purpose of our study was to determine the effect of high-intensity single-leg cycle training on insulin sensitivity and blood glucose levels in individuals with metabolic syndrome and insulin resistance, which put them at risk of developing T2DM. Seven individuals (age: 43 ± 14 yrs, height: 165.0 ± 11.6 cm, weight: 103.6 ± 17.7, BMI: 38.1 ± 5.6 kg/m 2) who displayed insulin resistance (CLIX-IR: 3.3 ± 1.2) and metabolic syndrome completed 12-14 sessions of high-intensity, interval based, single-leg training (HIIT) at a minimal intensity of 80% of VO2PEAK power. Pre- and postoral glucose tolerance, blood lipid, and VO2PEAK tests were performed to determine the effect of training on insulin resistance, blood glucose levels, and additional health parameters. One-way repeated measure ANOVAs showed that single-leg training significantly improved HbA1c levels (5.8 ± 0.5% pretraining vs. 5.6 ± 0.4% posttraining; p ≤ 0.05), and VO2PEAK capacity (1.4 ± 0.2 L/min pretraining vs. 1.7 ± 0.3 L/min posttraining; p ≤ 0.05). Though not significant, single-leg training also increased mean insulin resistance scores (CLIX-IR) by ~ 40% (3.3 ± 1.2 vs. 4.7 ± 2.9; p = 0.15). Our study demonstrates that HIIT can drive significant improvement in clinically relevant health measures such as HbA1c and VO2PEAK capacity in those at high risk for developing T2DM. Additionally, single-leg cycling is unique because it can minimize central hemodynamic stress (average heart-rate of 142 ± 15 beats/min at ≥ 80% of VO2PEAK) while still providing adequate peripheral stimulus to drive adaptation. This is of great benefit when re-introducing a sedentary population to exercise. |
