How to lose weight and prevent diabetes in 6 minutes a week
I believe regular movement and exercise is essential to health. As Stephan Guyenet pointed out in a recent blog post, our paleolithic ancestors had a different word for exercise: “life“. They naturally spent a lot of time outdoors in the sun, walking, hunting, gathering, and performing various other physically-oriented tasks. They had no concept of this as “exercise” or “working out”. It was just life.
But while exercise contributes to health in several different ways, it’s not very effective for weight loss. Or, more specifically, I should say that low-intensity, “cardio” – which is how most people exercise – is not effective for weight loss.
Why cardio doesn’t work
How could this be? There are three main reasons:
caloric burn during exercise is generally small;
people who exercise more also tend to eat more (which negates the weight regulating effect of exercise); and,
increasing specific periods of exercise may cause people to become more sedentary otherwise.
In an example of the first reason, a study following women over a one-year period found that in order to lose one kilogram (2.2 pounds) of fat, they had to exercise for an average of 77 hours. That’s a lot of time on the treadmill just to lose 2 pounds!
In an example of the second reason, a study found that people who exercise tend to eat more afterwards, and that they tend to crave high-calorie foods. The title of this study says it all: “Acute compensatory eating following exercise is associated with implicit hedonic wanting for food.” I love it when researchers have a sense of humor. Continue reading