When I first read studies which suggested that I could make significant and measurable changes to my fitness by doing just three minutes of exercise a week, I was incredulous [says Dr Michael Mosley].
You get on an exercise bike, warm up by doing gentle cycling for a couple of minutes, then go flat out for 20 seconds. A couple of minutes to catch your breath, then another 20 seconds at full throttle. Another couple of minutes gentle cycling, then a final 20 seconds going hell for leather. And that’s it.
So how does it work? According to Jamie, and other researchers I spoke to, part of the explanation is (probably) that HIT uses far more of our muscle tissue than classic aerobic exercise.
When you do HIT, you are using not just the leg muscles, but also the upper body including arms and shoulders, so that 80% of the body’s muscle cells are activated, compared to 20-40% for walking or moderate intensity jogging or cycling.
Areas to think about:
- Which markers of fitness may be impacted by HIT?
- Which would not be affected?
- The article goes on to discuss how genetic testing may predict the efficacy of HIT. How do you envisage genetic testing being used in health care more broadly in the future?