Towards the end of 2014 major fitness publications such as ACSM’s Health and Fitness Journal, Human Kinetics and even the Huffington post published articles on trend forecasting for 2015. With titles such as ‘Worldwide survey of fitness trends for 2015: what’s driving the market?’, ‘5 trends to expect in 2015’ and ‘Fitness Trend Forecast for 2015: 6 Trends on the rise’. A type of training and conditioning called High Intensity Interval Training (H.I.I.T or HIIT is the marketable acronym) made it on to all of these lists. Supporting the success of these trend forecasts, if you were to pick up any recent mainstream magazine, from a trash mag telling the reading public how a big celebrity star lost loads of lard in only 6 weeks working out 4 minutes a day, 2 times a week! Or a scientific journal sharing the positive research coming out supporting HIIT then we can see this is a trend worth while giving some of our time poor attention.
So what is HIIT?
Let’s break down the name to get an understanding of what HIIT truly is.
Part one – ‘High Intensity’.
In the world of strength, conditioning and fitness training High Intensity is defined as working very close to or at your maximum capacity. If you can lift 100 kilos then you are lifting very close to or at 100 kilos, if you can sprint 40 kilometres/hour then you are sprinting very close to 40 kilometres per hour, if heart rate is the gauge, then you are working at a minimum of 85% of your max heart rate (The VO2 max test or even the sub VO2 max test is a very effective way of getting your max heart rate).
The nature of working at high intensity is that you can only maintain such intensities or performances for a short period of time and it also comes with an inherent, rather obvious risk of injury. So to ward of potential injury and decreases in performance we enter into the next part of the acronym
Part two – ‘Interval’.
Just as the magic in a beautiful piece of music is due to the periods of silence between the notes, the published benefits of HIIT occurs as a result of the recovery period between your short bursts of high intensity lifting, sprinting, stationary biking or whatever movement you can do confidently. A biological rule of thumb to be obeyed here is that when one is working at high intensities a long rest period is coupled with that brief period of work.
For example a generalised program 30 seconds of work with 90 seconds of rest has been shown to be very effective. As below-
• Get on a stationary bike
• warm up
• sprint for 30 seconds as close to as fast as you can
• back off and pedal at a slow, recovery inducing rate for 90 seconds
• Repeat that process for a total of eight repetitions
Total amount of time getting uncomfortable and pushing at your limits = a very manageable 4 minutes (8 x 30 seconds), hence revert back to the trash mag “…working out 4 minutes a day”.
Total amount of time spent on the whole workout = a very attractive 20 minutes with warm up and cool down.
With time being our most prized resource (and number one excuse) HIIT can be perfect for those that believe they are too busy to work out or those that for some reason don’t enjoy exercising but will tolerate it in hopes of achieving a desired transformation.
Please note if it is true high intensity lifting you are using then your rest periods will be a minimum 2 minutes.
And Part 3 – ‘Training’
Seems obvious but let’s define training as a specific activity that stimulates a response from the body that serves to uplift fitness and health and does not undermine the latter in the process of enhancing the former.
This point is most important. The Centres for Disease Control and Prevention published in a National Health Survey that chronic and overuse type exercise related injuries in recreational and sports facilities have increased 4% over the past 10 years.
Unless you are an athlete with goals to be the best at what you do and you consciously acknowledge and are happy to deal with the consequences of the training to be in that upper echelon (most of us could not handle the sleep required let alone the training stress and fine line walked of injury and illness!) then this is our mantra and our final point of illumination on the semantics of HIIT.