Dr. Jason Fung

So if your body is normally using 2000 calories with your brain generating body heat, your heart, your lungs, your liver, they're using 2000 calories and now you go up to 2100 calories.

Well, percentage wise, it's not a huge deal, right?

The other problem with exercise is that it tends to actually cause you to eat more.

So again, we've had decades of study for this.

If you exercise, during the exercise, you have reduced appetite.

So you have, it's called exercise-induced anorexia.

So in the middle of a basketball game, you don't suddenly go, oh, wow, I'm really hungry, right?

Because your blood is flowing in your muscles and so on.

You're not thinking about the hunger.

So hunger actually goes down during exercise.

But after exercise, we see this rebound.

So we see that people are actually more hungry after exercise.

And if you're hungrier after exercise, it's gonna cause you to tend to gain more weight.

In fact, there's this very interesting study

that was done a few years ago in Harvard where they measured the sort of calorie difference that you get for children in certain activities.

So they said, okay, what if a child is watching TV?

What's the average caloric difference?

And it was like plus 100 calories per hour.

So for every hour of TV,

they're sort of positive 100 calories over time, right?