You might feel inclined to raid the kitchen and fill up the tank before a big workout, but new research suggests that may not be the way to go – at least when it comes to achieving weight loss.
In a study published in the American Journal of Physiology, researchers from the University of Bath detail how you’re likely to burn more fat if you forego food before hitting the gym.
Researchers studied a group of overweight men who walked for 60 minutes in two separate experiments; one while the men had empty stomachs and one two hours after they ate a high-calorie, carb-heavy breakfast.
Participants’ blood samples were taken after eating or fasting and then after walking. The gene expression in fat tissue differed dramatically in each situation, increasing when the participants fasted and exercised and decreasing when they ate and exercised. What this likely means is that stored fat was used to fuel metabolism during the workout instead of the carbohydrates from the meal.
Study author Dylan Thompson said that after eating, the fat 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.”
“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,” said Thompson.
Fat tissue plays an essential role during exercise, providing much of the energy for working skeletal muscle. Thompson said since fat tissue is influenced by weight loss and weight gain (with genes increasing in weight loss and decreasing in weight gain), their study suggests that “[eating] before exercise blunts some of the health-related changes induced by exercise training.”
Some of the study’s limitations include the small sample size and the fact that only the effects of skipping breakfast – not other meals – were studied. The research also doesn’t necessarily suggest that not eating before a workout will lead to accelerated weight loss.
Not to mention that saying no to a snack at any time of day for any reason is a lot easier said than done. We wish you luck in this profoundly challenging endeavour.
h/t The Independent