Does Exercise Work Best Before Or After A Meal?

If you are an exercise fanatic, would it be good to eat or fast before you work out? In a new study that examined the influence of eating versus fasting on gene expression in adipose (fat) tissue, scientists examined the diverse roles of fat on exercise.

Scientists from the University of Bath in the U.K examined a group of obese males. On empty stomach, they walked for an hour at 60 percent maximum oxygen consumption. In another experiment, they walked for a couple of hours after eating breakfast that was high-calorie and carbohydrate-rich, according to Science Daily.

The scientists examined the multiple blood samples after eating or fasting as well as post exercise. They also collected adipose tissue samples before and also an hour after their walk. Gene expression in the adipose tissue differed significantly in the two trials, according to a study published in the American Journal of Physiology -- Endocrinology and Metabolism.

The scientists found that the expression of PDK4 and HSL shot up when the men fasted and exercised, although they plummeted when the subjects ate before they walked. The scientists concluded that when the PDK4 went up, the stored fat would fuel metabolism while they exercised, not the carbohydrates that had been consumed. HSL tends to rise when adipose tissue uses stored energy in order to stoke activity or exercise, according to Netdoctor.

Hence, it can be concluded that "adipose tissue often faces competing challenges," Dylan Thompson, corresponding author of the study wrote. After a meal, a walker's adipose tissue tends to respond to it and does not stimulate or lead to favorable changes in adipose tissue. Hence, if a person exercises while fasting, he might undergo changes in the adipose tissue that are more favorable. This could help a person's health, in the long run, he wrote.

However, the response could vary according to different body styles. For most people, it does not really make such a big difference when fat loss is studied over a longer period of time. It would be best to just tap the state that is best suited to each person's training period, as it would be the workout that makes one feel and respond the best.