March 14, 2012
Seven Minutes a Week Improves Insulin Function ...
A string of studies have been published over the past couple years identifying a strong relationship between High Intensity Interval Training (HIIT) and reduced cardiovascular disease and metabolic syndrome risk. High Intensity Interval Training incorporates periods of exercise above 85% VO2max or HRR in alteration with periods of active or passive recuperation. Evidence suggests that smaller amounts of HIIT are more productive than larger amounts of moderate continuous training. No one is sure, however, how little HIIT and at what exact intensity optimize any variable measured.
Last month a study published in the journal Biomed Central Endocrine Disorders indicated that insulin sensitivity may be improved with as little as 7 minutes of exercise per week. Astounding!
Researchers in England studied 16 young healthy men. Participants completed between 4 and 6 thirty-second sprints on a cycle ergometer in 6 sessions over two weeks. In total, the participants had accumulated 15 minutes of exercise in that time period. An oral glucose tolerance test was administered at baseline and after completing the two week intervention. Researchers also measured aerobic performance using a self-paced time trial.
After two weeks of HIIT it was determined that insulin sensitivity had improved by 23% along with a 6% increase in aerobic cycling performance. Although fasting measures of glucose and insulin were unchanged, participants showed better glucose management during the glucose tolerance test.
Compliance is potentially the most difficult obstacle to overcome in exercise programming. If less commitment is necessary to experience optimal benefits a larger number of currently inactive individuals might be more successful in formulating an exercise habit. The results of this study truly support the old adage that "something is better than nothing" ... as long as you work hard enough.
Babraj, J.A., et al (2009) Extremely short duration high intensity interval training substantially improves insulin action in young healthy males BMC Endocrine Disorders 2009, 9:3 doi:10.1186/1472-6823-9-3