Australian scientist Dr Karl Kruszelnicki has shared the best time of day to work out if you want to lose weight, revealing that those trying to shed kilos can be see much better results by exercising before breakfast.

In a clip posted to TikTok, Dr Karl, 73, discussed a 2010 University of Belgium study that compared groups on the same diet compared to when they exercised and found that those who did endurance work on an empty stomach had the best results.

In the now viral video, Dr Karl revealed how one group in the study did no exercise, another exercised after eating and the third before eating. 

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Australian celebrity scientist Dr Karl Kruszelnicki has shared the best time of day to work out if you want to lose weight, revealing that those trying to shed kilos can be see much better results by exercising before breakfast

Australian celebrity scientist Dr Karl Kruszelnicki has shared the best time of day to work out if you want to lose weight, revealing that those trying to shed kilos can be see much better results by exercising before breakfast

All three groups increased their kilojoule intake by 30 per cent and ate a diet of 50 per cent fat.

‘Group one did no exercise and gained three kilograms, their blood chemistry was terrible,’ Dr Karl explained.

‘Group two did endurance exercise four days a week after breakfast, they gained 1.4kg and they’re blood chemistry was meh,’ he added.

‘Group three followed the same exercise programme as group two, but exercised before breakfast.

‘They gained 0.7kg, blood chemistry was normal,’ he added.

‘So it seems its best to exercise on an empty stomach if your goal is to lose weight’.

In a clip posted to TikTok , Dr Karl, 73, discussed a 2010 University of Belgium study that compared groups on the same diet compared to when they exercised and found that those who did endurance work on an empty stomach had the best results.

In the now viral video, Dr Karl revealed how one group in the study did no exercise, another exercised after eating and the third before eating

In a clip posted to TikTok , Dr Karl, 73, discussed a 2010 University of Belgium study that compared groups on the same diet compared to when they exercised and found that those who did endurance work on an empty stomach had the best results.

The research was based on a group of 27 healthy men, with an average age 21, and an average body weight of 71 kilograms.

Why do you lose more weight exercising on an empty stomach?  

Some scientist exercising on an empty stomach means your body feeds on stored fat and carbohydrates for energy instead of food you’ve recently eaten. 

This leads to higher levels of fat loss. 

After eating, the body is too busy responding to the meal consumed to focus on burning calories. 

This means exercising straight after eating won’t help to shift any excess pounds in the form of adipose tissue (fat).

Instead, the body uses the consumed carbohydrates as its energy source – not the desired form fat people want to shift.

However, there is some research that dispels this theory.

A 2014 study on 20 women found no significant differences in body composition changes between groups who ate or fasted before working out.

Working out on an empty stomach could also lead your body to use protein as fuel, which is needed to build and repair muscles after exercise.

While Dr Karl said there ‘wasn’t enough diversity’ in the study, and it was a small sample size, he said it’s a good starting point for future research.

Many recent studies have found that going to the gym on an empty stomach will burn more fat, especially in the morning. 

A 2017 study published in the American Journal of Physiology – Endocrinology and Metabolism by the University of Bath found that going to the gym while in a fasted state may help to burn the fat and even turn it into muscle.

Study author Dylan Thompson, of the University of Bath, said that adipose tissue – commonly known as body fat – often faces competing challenges after eating. 

After eating, this tissue ‘is busy responding to the meal and a bout of exercise at this time will not stimulate the same [beneficial] changes in adipose tissue’.

He added: ‘This means that exercise in a fasted state might provoke more favourable changes in adipose tissue, and this could be beneficial for health in the long term.’

Another study in 2013 found that early risers who exercise on an empty stomach before breakfast can burn up to 20 per cent more body fat.

Researchers discovered that those who had exercised in the morning did not consume additional calories or experience increased appetite during the day to compensate for their earlier activity.

They also found that those who had exercised in a fasted state burned almost 20 per cent more fat compared to those who had consumed breakfast before their workout.

In 2019, a joint study from Universities of Bath and Birmingham found exercising in a fasted state helps people control their blood sugar levels more than working out post-meal. 

Their body becomes efficient at using insulin, called ‘insulin sensitive’, which is generally seen as a sign of good health.

Keeping insulin in check has the potential to fight type 2 diabetes and other metabolic conditions.

While Dr Karl said there 'wasn't enough diversity' in the study, and it was a small sample size, he said it's a good starting point for future research.

While Dr Karl said there ‘wasn’t enough diversity’ in the study, and it was a small sample size, he said it’s a good starting point for future research.

For six weeks, one group ate breakfast before exercise and one after – as well as a control group. All participants ate dinner at 8pm the night before.

The breakfast was a high carbohydrate shake. The participants were also given a placebo drink before or after the exercise, depending on which group they were in.

The group who exercised before breakfast increased their ability to respond to insulin however both exercise groups lost a similar amount of weight and both gained a similar amount of fitness.

Topics #Alternative #Beauty #Health Care #Medicine #Popular Diets