There is a growing body of evidence that short duration high intensity training provides physiological adaptations similar to longer duration moderate intensity training. The first studies examining the potential of what is often referred to as HIIT (high intensity interval training) are decades old – but until recently the methods did not receive much attention. In the last few years, however – partly due to the surge in popularity of programs that incorporate HIIT principals like CrossFit, perhaps – the benefits of HIIT have been more widely reported.
For someone with limited time and high ambition, HIIT is good news. By training harder for shorter periods of time, one can potentially reach the same fitness level (and thus maintain the same competitive ability) as someone training many more hours but following traditional programs aimed at endurance athletes.
Consider for example someone training for a marathons – most beginner/intermediate programs will have them running between 25 and 50 miles per week. Many programs focus exclusively on number of miles (take a look here at the results of a quick google search of marathon training programs) and don’t prescribe intensity at all. Athletes taking up these programs typically spend all of their time at moderate to low intensities and depending on their typical per mile pace would be committing 3-7+ hours a week to training. Using mostly HIIT training an athlete might expect to be in as good of shape and perform as well during races and only train a 1/4 to a 1/3 of that.
It seems hard to believe, right? If the claims of HIIT were true, you might ask – why don’t we see more recreational athletes using them regularly and doing more/better on fewer training hours? And why are true low-volume training programs so damn near impossible to find?
The answer: HIIT is hard.
True HIIT – the kind of concerted near maximal effort that make up my three 10 minute work-week training sessions – isn’t something most people want to do. So while some training programs might flirt with the edges of ‘high intensity’ on occasion, many are targeted towards more recreational athletes never approach it. If you’re aiming to achieve any sort of serious fitness with total weekly training times measured in minutes not hours, however, you will need to become intimate with the pain of high intensity work. And it HURTS. A lot.
But if you can do it, it works. And it can lead to a level of fitness that is sufficient, at least in my experience, to attempt even really big events. Of course it won’t make those events easy, and the lack of traditional ‘big volume days’ might leave an athlete a little low on confidence heading into them – a fact that might make even those capable of regular HIIT efforts favor conventional programs. For those that already possess that confidence – or are willing to embrace the trial by fire mentality and risk failure to get it – the a HIIT low volume approach could be attractive.
Andy Magness is a 37 year old amateur athlete and adventurer based in Grand Forks, North Dakota . He strives to find the balance between work, family, and an outrageous desire to be fit enough to ‘do anything’. His blog threehoursaweek.blogspot.com chronicles his attempt to ‘do more with less’.