There has been alot of hype surrounding HIIT in the past few years and it shows no sign of slowing down. This hype has captured the interest of health researchers at various educational institutions and sparked further investigation. In this post I will show some of the hard scientific research that shows HIIT is an effective way of burning fat.

1. EXCESS POSTEXERCISE OXYGEN CONSUMPTION AND INTERVAL TRAINING (Shinichi Asano, Marshall University)
Link: http://www.marshall.edu/etd/masters/asano-shinichi-2005-ma.pdf

Please note, in this study HIIT is referred to as High Intensity Interval Exercise (HIIE).

The effect of exercise intensity on excess postexercise oxygen consumption (EPOC) was determined in 18 to 30 year old apparently healthy individuals. Subjects participated in 3 different exercise sessions; aerobic exercise, interval exercise (IE) and high intensity interval exercise (HIIE), on separate days. EPOC was measured one hour after each exercise while subjects were in supine position…

…There was no significant difference (p < 0.05) between mean EPOC of aerobic exercise and IE, however, a significant difference (p < 0.05) was found in mean EPOC of HIIE when it was compared with both aerobic exercise and IE. These data suggest that exercise intensity has a significant effect on EPOC.

2. THE EFFECTS OF INTERVAL TRAINING AND MODEST CALORIE RESTRICTION IN THE TREATMENT OF OBESITY (Stockunas, Michelle Marie, Virginia Tech)
Link: http://scholar.lib.vt.edu/theses/available/etd-09112000-21190050/

Moderate intensity exercise (MIT) was compared to high intensity interval exercise (HIIT) as part of a nine week treatment strategy for 13 obese men. Both groups exercised three days per week beginning at 45% VO2max. The MIT protocol progressed to 65% VO2max by week eight. The HIIT protocol consisting of 16 short (30 s), 8 medium (90 s), and 4 long (180 s) intervals progressed to 110% VO2max, 100% VO2max, and 90% VO2max, respectively, by week nine with low intensity intervals at 40% VO2max…

…The data suggest that HIIT may be more effective over a longer treatment period if the observed trend for greater capacity for muscle fat oxidation translates into improved body fat loss.

3. Short-term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance (Gibala, et al. McMaster University)
Link: http://jp.physoc.org/…&sortspec=relevance&resourcetype=HWCIT#SEC1

Please note, in this study HIIT is referred to as SIT or Sprint Interval Training.

…the most striking finding from the present study was that two very diverse forms of training induced remarkably similar changes in exercise capacity and selected muscle adaptations that are related to exercise tolerance. Given the markedly lower training volume in the SIT group, our results suggest that intense interval training is indeed a time-efficient strategy to induce rapid muscle and performance adaptations comparable to traditional endurance training. Additional research is warranted to clarify the effect of different acute exercise ‘impulses’ on molecular signalling events in human skeletal muscle, and the precise time course and mechanisms responsible for the contraction-induced changes that facilitate the training adaptation.

4. Two weeks of high-intensity aerobic interval training increases the capacity for fat oxidation during exercise in women (Talianan, et al. University of Guelph)
Link: http://jap.physiology.org/cgi/content/abstract/102/4/1439

Our aim was to examine the effects of seven high-intensity aerobic interval training (HIIT) sessions over 2 wk on skeletal muscle fuel content, mitochondrial enzyme activities, fatty acid transport proteins, peak O2 consumption (VO2 peak), and whole body metabolic, hormonal, and cardiovascular responses to exercise…

…In summary, seven sessions of HIIT over 2 wk induced marked increases in whole body and skeletal muscle capacity for fatty acid oxidation during exercise in moderately active women.

There you have it, 4 research studies to get you started on learning the science of HIIT. If you come across any more please submit them using the contact for and I’ll post them up.