This is why you shouldn’t do a HIIT workout at the end of a stressful day

HIIT workouts are, for many, a quick and efficient way to fit exercise into your schedule. Most HIIT (that’s high-intensity interval training, for the uninitiated) routines focus on achieving optimum results in a short amount of time, and there are thousands who swear by the method. In fact, recent studies from the British Medical Journal found that the bursts of effort that HIIT requires could even be more effective for weight loss than longer steady-state exercise.

However, while HIIT may have proven itself as a worthy workout in general, it’s important to remember that it’s not always right for every body, or indeed every moment – as personal trainer and bestselling author Alice Liveing pointed out to her 638k followers on Instagram recently.

HIIT cortisol stress
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In her post, which addressed the question ‘should I be doing HIIT?’, Alice addressed the recent study, explaining why a HIIT session to the end of an already stressful day may not be the best move.

‘It isn’t always conducive to our lifestyles,’ she wrote. ‘We are all STRESSED nowadays, and to finish a busy working day with cortisol levels high and then fly into a HIIT workout isn’t IMO healthy. It’s fine in moderation, but choosing HIIT as your only form of exercise isn’t something I’d advocate.’

In addition, she pointed out that HIIT can be difficult for beginners –  it ‘has an increased risk of injury and imposes higher cardiovascular stress’ on those who are not used to such intense exercise – and that actually, any form of movement can carry benefits, particularly when you focus on enjoyment, and couple it with nutritious food.

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Should I be doing HIIT? ⁣ ⁣ An article was posted in the British Journal of Sports Medicine examining whether interval training was the ‘magic bullet’ for fat loss (linked in my stories). ⁣ ⁣ The study gathered data from 36 previous studies that had conducted research in this area and came up with some interesting findings. But, also, left some holes… So I thought I would share my thoughts on it, as I know so many will be convinced that HIIT is the be all and end all of training, and I am inclined to disagree. ⁣ ⁣ Firstly, what is HIIT? True HIIT, and the modalities included in the above studies were sadly not the ‘insta-HIIT’ that does the rounds on here. True high intensity interval training is generally defined as cardiovascular exercise which involves repeated brief bursts of intense effort, interspersed with recovery periods. Cycling, swimming, running and boxing are all good examples. Due to the high level of exertion within true HIIT, they are usually shorter sessions which can last anywhere from 4 minutes up to around 20-30 minutes. ⁣ ⁣ ⁣ So, why did the study suggest it was so great? The outcomes from the analysis were that HIIT seemed to demonstrate a greater fat loss return than moderate intensity workouts that lasted between 30-45 minutes. This was despite the fact that the caloric burn in these moderate sessions was sometimes higher. They therefore suggest that HIIT is perhaps a greater tool for fat loss than traditional forms of cardiovascular exercise, perhaps, although they did not confirm the exact reason as to why this may be (e.g metabolism, adherence, appetite etc but this is another conversation that we can talk about another time). ⁣ ⁣ So, what do I think? ⁣ ⁣ 1 This study solely focuses on fat loss, which IMO is one of the weaker proven benefits of exercise, of which there are MANY. Stress relief, improved bone density, greater muscle mass, enjoyment, improved mental health… the list goes on, and these can all be achieved through a huge variety of exercises that you ENJOY. By simply discussing exercise in fat loss terms, it negates all of the other important positive benefits that it brings. ⁣ ⁣ 2 The barrier to entry with HIIT is HIGH.

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‘To summarise… is HIIT the be all and end all? In my opinion, no,’ Alice concluded. ‘If fat loss is your goal, incorporating it a few times a week MAY be ok, but don’t see it as the panacea of exercise, as it simply isn’t. Any form of movement that increases your energy output CAN contribute towards fat loss… if that is your goal.’

The comment section was also flooded with fitness fans applauding her remarks: ‘Great post couldn’t agree more,’ said one. ‘I was doing HIIT sessions 3-4 times a week but because I was so stressed I wasn’t losing weight I was gaining as my cortisol levels were high. I prefer now a mix of running, walking, pilates, yoga and boxing.’

‘Thanks for this! If you’re running in stress all day and the do a HIIT it’s adding fuel to the fire,’ another agreed. ‘Try pilates or yoga instead!’