Physical activity and health

Abstract EN

-A gain in body weight results from a long-term imbalance between energy intake and energy expenditure.

Apart from genetic factors, likely causes of overweight are reduced physical activity, excess energy intake, or both.

Under conditions of energy need, the body metabolizes all available fuels and diet composition has no impact on the amount or rate of weight loss.

In contrast, when energy is consumed in excess, it is disposed of according to an oxidative hierarchy.

Whereas excess carbohydrate and protein promote their own oxidation, dietary fat does not.

As a result, increased fat intake, typically associated with a consumption of a varied and energy-dense diet, can lead to increased fat storage.

Physical activity can restore energy balance and so prevent weight gain.

Though carbohydrate is an important fuel for exercise, its body stores are small in comparison to those of fat and protein.

Carbohydrate consumption during intensive exercise, whether in liquid or solid form, optimizes exercise performance by virtue of sparing glycogen stores.

In contrast, low intensity aerobic exercise increases the oxidation of fat and so contributes to weight control.

Aerobic exercise can be maintained for long periods of time, in trained individuals, with fat oxidation proportionally increasing with time.

As physical activity moves the energy equation in the direction of greater energy need, diet composition plays a lesser role.

An exercise prescription together with a balanced diet is the key to shaping health habits, especially for adolescents