Article by the Drummond Clinic
With this topic being high profile this week on the Horizon programme – Is this type of training a Fad or is it here to stay. Below is what is being said about HIIT. Remember, there are many ways to reach the end of a physiological goal. Is this the one?
What is it?
HIIT stands for High Intensity Interval Training or High Intensity Intermittent Training. It is an interval type workout that alternates between intense bursts of activity and periods of complete rest or recovery exercise. It is purported that 15 minutes can deliver the same physiological benefits as three hours of LSD (long slow distance) running. The benefits include a reduced risk of strokes, diabetes and heart attacks as well as improved endurance, but we will talk more about the benefits later on.
Who is it for?
Anyone can benefit from HIIT, right from beginners to elite athletes, however the form of exercise and the intensity will need to be varied depending on the individual or groups’ training age.
A number of studies have been done on the effectiveness of HIIT, and the following benefits are from a number of studies done on this type of training – see below for details of studies.
1) Aerobic – There have been many studies reporting an increase in aerobic capacity. A study by Driller showed an 8.2 second improvement in 2000m rowing time following 4 weeks of HIIT in well-trained rowers. This equates to a significant 2% improvement after just 7 interval training sessions. However, on the flip side, one study  that tested sedentary, overweight subjects found traditional exercise to be more effective. Maybe, one of the reasons for this is that for HIIT to be effective it needs to be near enough maximal and trained individuals are more likely to be able to work out maximal intensity than sedentary individuals. Is it something for PTs to use with their clients – well that depends on the client and only the PT will know if they would be willing to go that hard, but in my opinion I would say YES!
2) Metabolic – A study by King, found that HIIT increases the resting metabolic rate for the following 24 hours due to excess post-exercise oxygen consumption and likewise a stud by Trapp et al(4) found HIIT three times per week for 15 weeks compared to the same frequency of steady state exercise(SSE) was associated with significant reductions in total body fat and subcutaneous leg and trunk fat.
These two benefits are brilliant however they are to be taken with caution. Although HIIT training has been shown to have aerobic benefits I am not so sure that by solely doing this type of training 3 times a week, it will make you a better runner or triathlete, but it certainly seems like it could be a good addition to a program.
The biggest benefit in my opinion is the time it takes to get an effective workout. Research has shown that only 15minutes of HIIT is required to get the benefits stated above. Various types of HIIT have come about and claim to be the most efficient and we will discuss these a bit later. So for all those people who claim they don’t have enough time in their day, 30 minutes – consisting of 5mins foam roll, 5 minutes warm-up, 15 minutes HIIT and 5 minutes cool down and stretch – is all they need to find!
As well as finding time the other barrier to exercise often cited is ‘I don’t have a gym membership’ or ‘I don’t have any equipment’. The beauty of this type of training is that your bodyweight, if used correctly, is enough. A circuit of squat jumps, gun drills, star jumps, press-ups, sit-ups completed at maximum intensity will certainly get your heart rate high. However if equipment is available, then equally as good are cardio machines such as the rowing ergo, the bike ergo etc.
The fact that equipment is not essential also means that this can be done anywhere – even on business trips!!!
And lastly there is a stigma attached to this type of exercise from a number of women – ‘I don’t want to bulk up or look like a Russian shot-putter’ – then the study by Stokes et al (5)found that HIIT stimulated the production of HGH (Human Growth Hormone) by up to 450% during the 24 hours post workout – this is the same HGH that slows down the ageing process!!!
This type of training is becoming more popular, with many examples out there using the various methods, such as Tabatta (20 secs exercise and 10 secs rest), however, most people are coming up with their own variances, such as Insanity – a very good, but hard, at home workout using this type of training.
One of the fastest growing trends across gyms in the UK is the 30 min intense workout class – this takes on board the principles of HIIT and varies it from gym to gym into an individual class format.
Overall I believe this is a great way to train, although I believe it should be a supplement to exercise and not the only form of exercise performed. It takes quite a toll on the body and can often take a few days to recover from, especially if done at the near maximum intensity stated. So in this case those days in between will need to be filled with other forms of exercise or pre-habilitation work in the form of stretching, foam rolling or massage.
For more information on this or any type of training, please give one of our clinical team a call. HIIT can be for Rehabilitation, General Activity and Sports Performance – You choose.
1) Driller Matthew, Fell James, Gregory John, Shing Cecilia, Williams Andrew (2009). “The effects of high-intensity interval training in well-trained rowers”. International Journal of Sports Physiology and Performance 4: 1.
2) Venables, Michelle. “Endurance Training and obesity: effect on substrate metabolism and insulin sensitivity”. Edgbaston, UK: School of Sport and Exercise Sciences, The University of Birmingham. PMID 18379212.
3) King, Jeffrey W.. A Comparison of the Effects of Interval Training vs. Continuous Training on Weight Loss and Body Composition in Obese Pre-Menopausal Women (M.A.thesis). East Tennessee State University.
4) Trapp EG, Chisholm DJ, Freund J, Boutcher SH (April 2008). “The effects of high-intensity intermittent exercise training on fat loss and fasting insulin levels of young women”.International Journal of Obesity 32 (4): 684 – 91. doi:10.1038/sj.ijo.0803781.PMID18197184.
5) Stokes KA, Nevill ME, Hall GM, Lakomy HK. The time course of the human growth hormone response to a 6 s and a 30 s cycle ergometer sprint. Department of Physical Education, Sports Science and Recreation Management, Loughborough University, UK.