Science Backed Workouts Trigger The 'After Burn' Effect

High Intensity Interval Training, or HIIT as it is more commonly known, is the latest training craze that focuses on getting you in and out of your workout quick, with an emphasis on short, near-maximum intensity bursts followed by short periods of rest.

The result of HIIT is the triggering the EPOC or “after burn” effect, a recovery mechanism triggered by our bodies following a workout. The more intense your training session, the more energy your body requires to recover. The repair process burns energy, which means more calories, and the good news is, according to Industry expert David Allan, is this calorie deluge can last for up to 38 hours post your workout.

“HIIT training has been used by athletes and fitness professionals for decades, and is proven to be a very effective way of both increasing your overall fitness while maximising your calorie burn,” says Mr Allan, Founder and Studio Director at 38X Fitness.

38X Fitness as it is appropriately named, uses the science of the EPOC effect as the foundation of its group fitness workouts, which is proven to burn extra calories for up to 38 hours, well after your workout is completed.

“Most people think that calorie burn only happens when you are exercising, says David. If you train at the right intensity, you will actually burn more calories after your workout – sitting at your desk, on the ferry, and even while you sleep.”

He says the trick to turning your body into a fat burning machine is to train within a range of 80-90% of your heart rate for short intervals, with the goal of spending 15-20 minutes of a 55 minute workout in the “after burn” zone. To help achieve this, his studio is decked out with the latest in heart rate tracking technology, beamed to large screens spread throughout the studio. Sydney’s best fitness coaches leads groups of 10-20 people through a very specific workout, taking the intensity up and down throughout to ensure each participant spends enough time in the red to trigger the after burn.

“Each participants name and live heart rate reading is on screen for all to see – including the coach, so there is real motivation to get the best out of every session, he says. The beauty of this approach is everyone rallies together and lifts during the intensity intervals, much like a team environment, and no-one wants to let the team down. The result is maximum effort in minimal time, and the results our clients are achieving are some of the greatest I have seen in my time in the fitness industry.”

He says HIIT is not for everyone, but his classes cater for beginners to elite athletes.

“The beauty of heart rate based training is you are your own benchmark, you don’t need to compete with anyone, it’s all about working to your best level to get the results. As long as you spend the right amount of time in the red zone, you will see results.”

David says that just two 38X workouts per week is enough for people to see changes.

“The beauty of HIIT is you can spend less time to achieve more – it’s simply using the science that athletes and elite coaches have used for years as a foundation to maximise your results.”

For more information on 38X and the after burn effect, visit

38X Fitness

1/167 Pittwater Rd, Manly | Ph: (02) 80968 0888

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