HIIT or High Intensity Interval Training is the process of training at an extremely high intensity for short periods of time.  It is recommended the subject reaches peaks of 90-95% of their maximum heart rate, with short rest breaks, for between 20 – 60 minutes.

At this point I want to discuss a few things before I go on. Training is an individual thing. The factors affecting training abilities are age, body type, sex, current fitness and genes medical conditions etc. Two people training side by side doing the same thing will not feel exactly the same. As in, one fit person training with a unfit person will have different “rates of perceived exertion”. The fit person may be training at coasting 50% or their maximum ability where as the unfit person may be struggling at 80% and won’t have much more to give. SO the best indicator across all people is their max heart rate for their age. (220 beats per minute – age). Endurance training for anyone places their heart rate in the 65-75% zone. HIIT places their heart rate in 85-95% zone regardless of the various factors mentioned above. NB consult a doctor before beginning or increasing your training intensity.

There have been numerous studies showing that HIIT is superior to Endurance Training (ET) for weight loss.

I want to quote the “Journal of Applied Physiology Published 1 December 2011 VOL. 111 no. 6.”  (Please don’t be put off by the big words, I will decipher them.)

“HIIT has been shown to be more effective than moderate-intensity continuous exercise training for improving endothelial function (normal functioning of the inner lining of blood vessel) and ….. for reducing central body fat (losing weight) and fasting plasma insulin in young women (improves diabetes risk), and for improving maximal oxygen uptake (getting oxygen into your system) in subjects… HIIT has also been reported to be more effective than continuous, steady-state exercise training for inducing fat loss in men and women, despite considerably less total energy expenditure required during training sessions.“

I may have already lost a few of you here, and I won’t turn the rest of you away by explaining too deeply why this is the case. You have a car…It runs and you don’t care why. HIIT kicks Endurance Training and that’s a fact.

This particular article sited above goes on to say the HIIT sessions can last from as short as 8 seconds and typically from 1-4 minutes per set. With 60 seconds rest between each set.

SO a typical session may look like this:

• 5-10 minute warm up 65-75% max heart rate. (That’s jogging/exercising at a mild puff)
• 5 minute stretching session targeting large muscle groups
• 5 by x minute HIIT sessions + 60 seconds rest
  • (5×60 second plus 60 seconds rest equals 10 minutes work out)
  • (5×90 second plus 60 seconds rest equals approx. 14 minutes work out)
  • (5×120 second plus 60 seconds rest equals approx. 20 minutes work out) You get the idea
• 5-10 minute warm down 65-75% max heart rate
• 5 minute stretching session targeting large muscle groups

SO a basic session can be short as 30 minutes and can be broken down

Assuming 5 x 30 second HIIT sets

• 10 minutes total warm up cool down
• 10 minutes stretching
• 5 minutes HIIT
• 5 minutes rest

A more advanced session (assuming 5 x 120 second HIIT) sets looks like this:

• 10 minutes total warm up cool down
• 10 minutes stretching
• 10 minutes HIIT
• 5 minutes rest

That’s still only 10 minutes of extremely high heart rate.

SO if you have read this far. This is the crunch line…

Essentially the chemical processes that occur or chemicals that are released in the body at this very high heart rate continue to keep the metabolism high and burn fat at a higher rate for longer. This is why HIIT is superior to normal endurance training.