Why doing more exercise won't help you burn more calories

Most of us believe that if calories out (used) exceed calories in, you will lose weight, and it is the reason why exercise combined with diet is advised by many to stay trim and loose weight. But as many of us know, increasing activity doesn’t seem to have much impact on losing body-weight.

In a recent article in New Scientist, looks into this idea and discusses how things are much weirder than the simplistic calories in and calories out. It seems that working out more doesn’t appear to burn more calories than doing less. In fact, it doesn’t seem that exercising very hard uses more calories than moderate activity a few days a week.

The problem is that exercise accounts for a small portion of daily calorie expenditure. Most calories are utilized for:

  1. Essential body functions when the body is at rest or the basal metabolic rate

  2. The energy needed to break down food during digestion

  3. And the portion that we tend to think about, the energy used in physical activity

In most people, the basal metabolic rate accounts for 60 to 80 percent of total energy expenditure and digesting food for about 10 percent. Therefore, physical activity accounts for only 10 to 30 percent of total energy expenditure. Hence any weight loss effort should be aimed at looking at food intake and basal metabolic rate, as this is where significant changes body composition are made.

This does not mean that you have to stop exercising, as exercise has enormous health benefits. Exercise has been linking with improvements in blood pressure, cholesterol, and sugar, bolstering sleep, attention, energy and mood, decreasing cancer, to name a few. So, although it has been called the world’s best health drug, it is not a weight-loss drug.

It is a disservice to continue pushing exercise as the gold standard for weight loss and preventing obesity. This misinforms everyone of the realities of long-term weight loss and management and the incredible benefits of regular exercise on health.

See article in New Scientist on 16 Jan 2019