To Lose Weight, Do You Exercise On An Empty Stomach?
Do you have to eat or not before you do the exercise when you’re overweight? Opinions (and studies) gave mixed results. A new clinical trial is the first of its kind to record what happens in adipose tissue (body fat) in response to exercise, depending on whether we are fasting or eating.
Researchers at the University of Bath (UK) have enrolled a group of overweight men. They were asked to walk for an hour at 60 percent of maximal oxygen consumption, once on an empty stomach, and another two hours after consuming a high calorie carbohydrate breakfast. Blood and fat samples were collected before the walking session and an hour later.
Expression of genes in adipose tissue differed significantly in both trials. The expression of two genes, PDK4 and HSL, increased when men fasted and decreased when they took the snack. The increased activity of these two genes indicates that body fat was used as a source of energy, in preference to meal carbohydrates, the researchers said.
These findings reinforce the idea that after a meal, adipose tissue ” is busy responding to energy intake and an exercise session at this time will not have the same changes Beneficial effects in adipose tissue. So, when you’re overweight, it’s best to do an exercise session on an empty stomach. “
This opinion is valid for the moment only for a session of exercise of moderate intensity, except search for performance. And of course only if you are not indisposed by having an empty stomach (nausea, dizziness). Moreover, the researchers did not test the effects of a diet rich in fats or proteins, nor made an assessment after several days.