"It is possible to gain significant health benefits from only 7.5 minutes of exercise each week -- if that is all that you find the time to do," Dr. James A. Timmons of Heriot-Watt University in Edinburgh, one of the researchers on the study, told Reuters Health.
"This is a dramatically different view from current thinking," he admitted.
Timmons and his team found that young sedentary men who did just 15 minutes of all-out sprinting on an exercise bike spread out over two weeks substantially improved their ability to metabolize glucose (sugar). Traditional aerobic exercise programs can boost sensitivity to the key blood-sugar-regulating hormone insulin. The high-intensity program did this too, but it also directly reduced the men's blood sugar levels -- something that standard exercise programs have not been shown to do.
Recommendations for high intensity, short duration exercise could one day replace current physical activity guidelines, Timmons said. "Only large scale trials could prove this," he said. "But there is mounting evidence that doing this new protocol will deliver the same reductions in risk factors. The key thing with exercise is the more routine you make it, the more likely you will benefit." And doing seven minutes of exercise a week, every week, he added, may be better than doing three hours a week just a few times a year.
Steve - now I won't feel so self-conscious when I end my weekly outdoor jog in my neighborhood with sprints!