The New Years brings new resolutions to look and feel our best, and to lose the unwanted pounds once and for all. In my own experience, I usually start out working at least an hour per day for the first 2 weeks. The fitness enthusiasm declines precipitously by the end of January and old sedentary habits feel too hard to break. But this year however, I am trying something different – short yet effective workouts scientifically proven to aid weight loss and improve health. It’s called HIIT – High Intensity Interval Training and here’s why you should HIIT it too!

Science says ditch the traditional workouts

Did you know you can burn “9 times the fat (calories) with 30 minutes of high-intensity aerobic / anaerobic exercise than 30-40 minutes on treadmill?” That’s what a Canadian study found observing 27 inactive, healthy, non-obese adults between 18 and 32 years of age (Source: Tremblay et al, 1994).

Here are highlights from this pathbreaking study:

1. Though Group 1 burnt twice the calories during the workout, Group 2 continued burning calories after the exercise.
2. The biggest shocker – Group 2 lost up to 9 times more subcutaneous fat (responsible for cellulite women dread) in 15 weeks, than Group 1 lost in 21 weeks. Dr. Tremblay’s team looked at the muscle biopsies and muscle enzyme activity as well.
3. The metabolism was substantially raised in Group 2, whereas Group 1 experienced no additional calorie metabolism post the work-out.

Though the Canadian study had a small sample size and conducted in 1994, other recent studies noted similar effects.

1. HIIT was associated with decreased appetite, increased post-exercise oxygen consumption, and improved endurance (Source: Health Guidance).
2. In a popular study conducted by Professor Tabata indicated that 20 seconds of HIIT followed by 10 seconds of rest (for 8 cycles) helped Olympic speed skaters better than traditional steady-state training (Source: Tabata et al; 1996).
3. Professor Gilabala found that study participants who worked out 3 times a week of HIIT had the similar results compared to those working out at a steady-rate (Source: Gibala et al, 2012) (HIIT workout included 3 minutes of warm up, 60 seconds of intense exercise at 95% VO_2max, 75 seconds of rest, repeated 8-12 times, 3 minutes of cooldown. Steady-rate workout was at 50%-70% VO_2max).
4. In a more recent study from 2008, 27 obese women were exposed to either low-intensity exercise (5 days a week) or high intensity exercise (3 days a week) or no exercise (or existing exercise levels). The study found that women in the high intensity exercise group significantly reduced total abdominal fat, abdominal subcutaneous fat, and improved cardio respiratory fitness, compared to low-intensity exercise and no exercise groups (Source: Irving et al; 1998).

How will you HIIT it?

Given the benefits of HIIT with just 20-30 minutes of workout, Professor Hawley of Australia questions the traditional cardio-vascular training methods, and recommends high-intensity workouts as a potent and efficient workout method instead.

Based on our personal experience, we suggest some easy ways to incorporate HIIT into your workout regimen:

• 3 minutes of warm up (walking at brisk pace), followed by 8-12 repetitions of 60 seconds of intense activity (80%-95% heart rate) followed by 60 seconds of recovery and 3 minutes of cool down. We’ve tried this routine and the workout was painfully difficult but exceptionally invigorating. 
• This regimen can be adopted for running, biking, or other types of aerobic and strength training workouts.
• Note however, the high-intensity interval must burn. If you’re not ready to pass out by the end of the interval take the intensity up a couple of notches.
• HIIT should not be confused with Interval Training. In fact, HIIT is an enhanced form of Interval Training with short bursts of extreme aerobic activity followed by a short recovery period.
• 3 HIIT workouts a week are typically sufficient to begin with. However, performance can be adapted to improving endurance over time.

“Eat less and move more” is the commonly cited mantra to weight loss. But time spent moving  depends on the demands on our personal and professional time. Those with young families or exceptionally busy careers often find it hard to make time for exercise. They’d rather catch a breath curled up on the sofa than exercise for hours.

But most of us can manage to spare 20-30 minutes 3 times a week. Using those 20-30 minutes to exercise smartly and efficiently may bring the elusive weight loss results we’ve been awaiting for all along.

For all Freakonomics lovers, here’s a fun podcast you shouldn’t miss – What is the best exercise? Run through your exercise options and see what works best for you. We’re sticking to HIIT this year around.

References:

• Irving et al, Effect of exercise training intensity on abdominal visceral fat and body composition, Med Sci Sports Exerc. 2008 November; 40(11): 1863–1872. doi:10.1249/MSS.0b013e3181801d40, Link: http://www.carnevalijunior.com.br/wp-content/uploads/2010/03/effect-of-exercise-training-intensity-on-abdominal-visceral-fat-and-body-composition-20081.pdf
• Izumi Tabata; Kouji Nishimura, Hirai Motoki, Futoshi Ogita, Motohiko Miyachi, Kaoru Yamamoto, National Institute of Fitness and Sports in Tokyo, Japan Medicine & Science in Sports & Exercise. 28(10):1327-1330, October 1996
• J.A. Hawley, High-intensity interval training for health and performance: A polarized perspective, Proceedings of the Australian Physiological Society, Link: http://aups.org.au/Proceedings/44/94P/94P.pdf
• Martin J Gibala,¹ Jonathan P Little,² Maureen J MacDonald,¹ and John A Hawley^3, Physiological adaptations to low-volume, high-intensity interval training in health and disease, J Physiol. Mar 1, 2012; 590(Pt 5): 1077–1084. Link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3381816
• Tabata et al, Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max, Med Sci Sports Exerc. 1996 Oct;28(10):1327-30. Link – http://www.ncbi.nlm.nih.gov/pubmed/8897392
• Tremblay et al, Impact of exercise intensity on body fatness and skeletal muscle metabolism, Metabolism, Vol 43., No. 7 (July), 1994, page 814-818, Link: http://www.colorado.edu/intphys/Class/IPHY3700_Greene/TIPS/exIntesity/Tremblay.pdf

Read More:

• Studies and articles on benefits of high intensity short duration workouts
• Clients with no time need to HIIT it!
• HIIT Vs. Continuous Endurance Training: Battle Of The Aerobic Titans