Study finds that those who exercise before breakfast burn double the amount of fat than those who exercise after.
We hear much about miraculously effortless ways to burn fat – pills, potions, supplements, superfoods, you name it – and most of them turn out to be little more than pipe dreams. But now researchers from the Universities of Bath and Birmingham seem to have found onto a way in which people may actually be able to burn double the amount of fat for the same effort – no miracle potion required.
This trick? Exercise on an empty stomach. Yes, you still have to exercise – but if you are exercising already, according to the study you could be doubling some of the benefits by simply adjusting the timing.The study included 30 men who were classified as obese or overweight, and compared results from two intervention groups (who ate breakfast before/after exercise) and a control group (who made no lifestyle changes), explains the University of Bath.
After six weeks, they concluded that the participants who exercised before breakfast burned double the amount of fat than the group who exercised after breakfast. They found that this was happening because of lower insulin levels during exercise after having fasted, meaning more of the fat from fat tissue and the fat within muscles was being used as fuel.
The researchers found that the muscles from the group who exercised before breakfast were more responsive to insulin compared to the group who exercised after breakfast, despite having had the exact same training and food intake. The muscles from the pre-breakfast exercisers also had greater increases in key proteins, especially those involved in delivering glucose from the blood to the muscles
"Our results suggest that changing the timing of when you eat in relation to when you exercise can bring about profound and positive changes to your overall health," said Dr Javier Gonzalez of the Department for Health at the University of Bath.
"We found that the men in the study who exercised before breakfast burned double the amount of fat than the group who exercised after," he added. "Importantly, whilst this didn't have any effect on weight loss, it did dramatically improve their overall health."
And yes, there's that: There was no difference in weight loss. But that the pre-breakfast exercisers were better able to respond to insulin means they were better able to keep blood sugar levels under control and potentially lower the risk of diabetes and heart disease. Pretty remarkable just for changing the time of exercise versus eating.
That the study included just men is a bit of a bummer for women looking for a similar health boost, but they decided to focus on men only to test the proof-of-principle. They promise that future studies will explore the same principle for different groups, including women.
"This work suggests that performing exercise in the overnight-fasted state can increase the health benefits of exercise for individuals, without changing the intensity, duration or perception of their effort," said co-author Dr Gareth Wallis of the University of Birmingham. "We now need to explore the longer-term effects of this type of exercise and whether women benefit in the same way as men."
In the meantime, I'm going to keep exercising before breakfast – I prefer not working out of a full stomach anyway, if a little profound and positive fat-burning happens along the way, all the better.
The study was published in Journal of Clinical Endocrinology and Metabolism.