We receive so much contradictory advice about exercising that it can be hard to keep up with what’s good for us and what isn’t – whether we’re being told that marathons can damage our heart, running can damage our joints or that golf can damage our wrists, it can seem that there’s no one-size-fits-all solution when it comes to exercise. But there is one mandate we tend to stick to– and that’s the government’s recommendation that adults up-to the age of 64 do at least 150 minutes of moderate aerobic exercise a week, and strength exercises at least twice a week . But the rise of High Intensity Training (HIT) and High Intensity Interval Training (HIIT) now seems to challenge even this basic premise. But what is HIT, is it as effective as its hype implies, and is it only suitable for youngsters?
What is HIT?
Put simply, HIT involves performing repetitions of high intensity physical activity, followed by varying lengths of recovery times. The work out periods can last as little five seconds or as long as eight minutes, and are performed at 80-95% of a person’s estimated maximal heart rate (MHR). The recovery periods can last around the same amount of time, and are performed at 40-50% MHR . These workouts commonly last between 20-60 minutes, but evidence has shown that significant benefits can be conferred from as little as 10 minutes of HIT . Spin classes, boot camps and circuit training are all examples of HIT.
Does HIT live up to the hype?
The idea of exercising for as little as a few seconds at a time, followed by a nice rest may sound pretty appealing – but the key here is the word intensity. The idea is that you push yourself as hard as you can during the active part of your workout – and this has been shown to confer remarkable health benefits. A study carried out by Michael Mosely and Nottingham University found that, when sedentary individuals stuck to a month-long regime of doing 3 twelve-minute HIT sessions a week, their VO2 max test scores increased by 17%  – which researchers described as “huge, a really significant increase”.
A VO2 max test essentially tests the strength of a person’s lungs and heart, and is considered to be the strongest indicator of a person’s overall health– but HIT has also been shown to increase elasticity of arteries, enable to body to use oxygen and insulin more efficiently and improve fat-burning . So what’s the downside?
HIT isn’t just for youngsters
“Yes, that’s all well and good,” I can hear you thinking, “but I can’t do high intensity training at my age, I’ll have a stroke!” You’re not alone in this kind of thinking – HIT has been traditionally viewed as something for athletes wishing to gain a competitive edge, and those wanting to burn fat fast, only. But HIT’s health benefits are so compelling that it’s now being studied as an alternative to medicine for some high-risk individuals with chronic health problems, and some studies have even concluded that HIT “appears safe and better tolerated by patients [with coronary artery disease and heart failure] than moderate-intensity continuous exercise” . There’s a common misconception that “high intensity” means pushing oneself beyond all limits – but actually, it’s measured against what is “high intensity” for a particular person in their own health situation, not a universal standard.
Having said that, it’s not recommended to go running out and signing up to a fitness boot camp without getting clearance from your doctor first. If you’re an older person with health risks, it may be safer for you to work on HIT with a personal trainer who can monitor your activity and adjust activities to your particular needs, rather than go hell for leather in a group exercise class, or at home. It’s also advised that you work it into your regime slowly – for example, starting with one session a week, and seeing how your body tolerates it. But if your doctor approves, then the benefits of HIT speak for themselves – and you can get your workout in while you’re waiting for the kettle to boil. What could be more convenient than that?