High Intensity Interval Training (HIIT) is especially suitable for people who don’t have much time to exercise. As reported in this blog before, numerous studies have shown that HIIT gives maximum benefits in the shortest period of time. Today we will give you a formula that defines how short that time can be: 1 minute of intense exertion.
This formula was developed by researchers at McMaster University (Ontario, Canada). The researchers performed a rigorously scientific study, including actual muscle biopsies of each participant at the beginning of the study, and at the end of the study 12 weeks later. A muscle biopsy involves a cut into a muscle to take a sample, so this was a serious study. Besides the biopsy, they measured cardiorespiratory fitness and the glucose-insulin metabolism of the study participants, at the beginning and at the end of the 12 weeks of the study.
Twenty-five out-of-shape young men were recruited for the study, and then the men were randomly divided into three groups. The first group was asked to not change their current exercise routine, which for most of them, meant essentially no exercise at all. The second group was assigned to a typical aerobic training workout, of 50 minutes of moderate paced cycling on a stationary bike, three times per week.
The third group was assigned to do HIIT training. The interesting thing was that their total workout (outlined below) totaled only 10 minutes, three times per week. The results showed that at the end of the 12 weeks, that both groups that performed exercise showed the same improvements in the microscopic appearance of their muscles cells (looking at the power factory of the muscle cells—the mitochondria), and the same significant improvements in their cardiopulmonary fitness.
Amazingly, the amount of improvement in the two groups was essentially the same. Meaning, the ones who performed the HIIT routine for 10 minutes, three times per week, had the same improvement as the group who exercised for 50 minutes at moderate pace three times per week. Unsurprisingly, the group of men who did not change their exercise routine showed no improvements.
This study confirms previous studies showing that—for reasons not yet fully known—the body reacts to short periods of intense exercise very differently than to moderate exercise. But this study was extreme. It was the first to show that 1-minute of intense exercise was equivalent to 50 minutes of moderate training.
Here is the HIIT routine followed in this research study, if you want to try it yourself. You should only try HIIT if you are already doing exercise and are in reasonably good physical condition. Any question, talk to your doctor (best a sports medicine doctor or cardiologist).
HIIT routine, on a stationary bike:
1) 2 minutes of warm up at slow to moderate pace
2) 20 seconds of intense cycling (as hard as you can do)
3) 2 minutes very slow cycling
4) 20 seconds intense
5) 2 minutes very slow
6) 20 seconds intense
7) 3 minutes slow cool down
Total time: 10 minutes
Total time intense: 1 minute.
See also in ProcuraMed:
Esta postagem também está disponível em: Portuguese (Brazil)