This viewpoint is indeed quite unconventional; it startled me when I first saw it. I had been telling myself during the Lunar New Year holidays that I'd burn off all those calories through increased exercise afterward, but now I'm convinced I can't. So what's the basis for this claim? Let's take a look.

A cover story in Scientific American, written by anthropologist Herman Ponce, argues that people believe exercise helps with weight loss because it burns calories, or that exercise follows the law of conservation of energy, thus requiring energy expenditure.

Strangely, such simple common sense is rarely verified by scientific experiments. This is odd; how can something that seems perfectly reasonable lack evidence? Hermann decided to find the evidence himself, whether to prove or disprove it.

Through experiments, Hermann proposed that the energy consumed by humans each day is fixed, and that exercise is not directly related to energy consumption . The following two experiments can verify this viewpoint.

The first experiment involved Herman's team's long-term tracking and research of the Hadza people of Africa. Living on the Tanzanian highlands, they are among the last remaining hunter-gatherer communities in the world. This lifestyle dictates that their physical activity levels are far greater than those of modern city dwellers. So, do they also expend a tremendous amount of energy daily? Hadza men consume an average of 2600 calories per day, and women 1900 calories—a figure roughly equivalent to that of adults in the United States or Europe.

In the second experiment, researchers at Yola University Chicago collected 98 samples from African American women in Chicago, rural women in Nigeria, and people from all over the world. They found that people in developed cities and those engaged in manual labor in underdeveloped areas consumed roughly the same amount of energy each day.

Because the conclusion seemed counterintuitive, the researchers suspected a flaw in the experiment and conducted further investigations. They recruited hundreds of volunteers, including fitness enthusiasts, people who exercised moderately daily, people who rarely exercised, and people who spent their days lounging on the sofa watching TV. The researchers observed that the energy expenditure of those who exercised regularly was not significantly different from those who spent most of their time on the sofa watching TV; it was approximately 200 calories, about the same as a glass of milk.

The conclusion is clear: there is indeed no direct relationship between exercise and energy expenditure. So the question is, how do we humans accomplish more work or exercise without expending more energy? Scientists' answer is: we don't know . Don't be confused by this; scientists don't know everything, and because of their rigorous scientific approach, they may admit to not knowing more often than the average person. However, we can still be fairly certain that regardless of whether you exercise or not, your body adapts to high-intensity activities and tries to maintain roughly the same daily energy expenditure.

Since exercise doesn't burn more energy, the theoretical basis for using exercise to lose weight disappears. In other words, if you believe the above conclusion, then your only way to lose weight might be to control your diet. Oh, and maybe depression can also help with weight loss, but that's not really worth it.

One last question: what excuse will I use next time I want to indulge myself?