Researchers at McMaster University in Canada believe that the body can get as much benefit from ten short but intensive bursts of exercise, as it can from hours of moderate traning. HIT or “high intensive interval training” involves running or cycling (or swimming?) at almost maximum effort for a minute and then resting for about a minute before repeating the process around 10 times. The researchers recruited 7 men of average age 21 years and got them to perform 6 training sessions over 2 weeks. Each session comprised between 8 and 12 one-minute intervals at around 100% of peak power output, with each interval separated by 75 seconds of rest. An effort that they describe as beyond the comfort zone of most people (about 95 per cent of maximal heart rate), but only half of what might be regarded as an “all out” sprint.
Comparison of biopsy samples of the vastus lateralis muscle (the largest part of the quadriceps) before and after the 2 weeks of training showed increased maximal activity of mitochondrial capacity and other relevant chemical processes, that would have taken over 10 hours of continuous moderate exercise to obtain.
The researchers therefore conclude, that:
“This study demonstrates that a practical model of low volume HIT is a potent stimulus for increasing skeletal muscle mitochondrial capacity and improving exercise performance.”
… and …
“While still a demanding form of training, the exercise protocol we used should be possible to do by the general public and you don’t need more than an average exercise bike.”