High intensity interval training (HIIT) might seem like just another flash in the fitness pan, but here’s where it differs: it’s quick, it’s affordable and anyone can do it.
How HIIT works
HIIT pairs short periods of high-intensity exercise with periods of medium to low intensity ‘rest periods’, says Greg Hyson, a biokineticist at the Sports Science Institute of South Africa (SSISA). “The intervals are repeated several times, resulting in a short but tough workout.”
“For those with only half an hour to an hour available to train, HIIT offers an ideal opportunity to tone up and build some muscle, as well as lean down and shed some of those unwanted kilos,” adds Justin Swart, general manager and master trainer at 360 Specialized Training in Cape Town.
Swart explains the science behind the sweat: “During HIIT, all three of the body’s energy systems – the phosphagen (brief bursts of high-intensity activity), aerobic (slow/moderate and sustained activity/active recovery) and anaerobic (all-out, fast-paced, high intensity) energy systems – are utilised. A cleverly crafted HIIT session will allow the participant to enter the ‘fat burning zone’ sooner. Over time, by placing higher demands on the body, each energy system is required to work faster and more efficiently, therefore physiological changes take place in the muscles to allow for an increase in your VO2 max [widely accepted as the best measure of cardiovascular fitness].”
A fitter body means better fat and carbohydrate burning abilities, which translates to more energy to sustain exercise in that much desired “fat burning zone.” In other words, the fitter you become, the easier it is to make even more progress, whether your goal is to tone up, lose weight or train for an event.
Don’t skip the rest periods
“The rest periods are very important,” explains Hyson. “If the rest periods aren’t long enough, you won’t be able to maintain the desired high intensity. Most of the set protocols have a work to rest ratio of 1:1, meaning if you do a sprint for 30 seconds, you recover by walking or running lightly for another 30 seconds, then repeat. The amount of repetitions (cycles) performed will depend on level of fitness, work-to-rest ratios and which exercises are being performed.” Hyson advises that you aim to repeat these cycles between eight and 12 times for best results.
“If you’re not following a pre-determined work-to-rest ratio, an effective and safe way to determine whether you have rested sufficiently would be to wait until your heart rate has settled and your breathing has regulated,” adds Swart.
“HIIT workouts need not be very complicated nor require much equipment, the only element that needs to remain constant is the high intensity sets,” says Hyson.
“Anyone can do HIIT, as long as the session is appropriately designed and implemented for their age group and medical status. Beginners should look for shorter, slower bouts consisting of lower intensity, volume and frequency. Advanced candidates should look for a blend of longer and shorter bouts consisting of higher intensity, volume and frequency,” advises Swart.
“High intensity cardio bursts (primary) and simple body weight exercises (secondary) are the best way to begin HIIT,” says Hyson. “The best cardio exercise would include short sprints, skipping, cycling, jumping and boxing. Running is especially good as it uses almost all our major muscle groups. Remember that these are done at very high (90%) intensity for short periods of approximately 10-30 seconds with longer rest periods (up to 60) for recovery. Body weight exercises can be included, but must also be done at high intensity, without compromising technique.”
Try the 10-minute HIIT workout
1. Warm up with a one-minute walk.
2. Sprint flat out for 30 seconds.
3. Walk or jog at a comfortable pace for 30 to 60 seconds (until you get your breath back). Alternate between sprinting and walking or jogging for 10 minutes.
Prefer cycling or skipping? Just replace the running with your cardio exercise of choice – as long as you work up a serious sweat, you’re hitting your goal. As your fitness improves, you can decrease your rest intervals to 30 seconds or increase your total exercise time.
CAUTION: Always consult a medical doctor before starting a new exercise programme.