The most of us believe that more is better in terms of calorie burn and weight loss then a little exercise, a research team says that it’s not necessarily true. Their new study which is published in Current Biology, says that people who exercise a lot don’t burn extra calories for their efforts beyond a certain point.
But don’t give up the gym membership just yet, though. WebMD asked two experts to discuss these findings and the role of exercise.
The experts are: the study’s lead researcher, Herman Pontzer, PhD, a professor of anthropology at City University of New York, and Edward L. Melanson, PhD, an associate professor in the division of endocrinology, metabolism, and diabetes at the University of Colorado Anschutz Medical Campus, Aurora.
They both agree on one thing: The new research provides more evidence that diet, not exercise, is the key to losing weight, but also is not discouraging exercise, which is crucial to keeping your body and mind healthy.
What did the study find?
Pontzer and his team conducted a research in which they measured the daily activity levels of more than 300 men and women, along with how many calories they burned over the course of a week. They came from five different countries across Africa and North America: the Seychelles, Jamaica, the U.S., Ghana, and South Africa. Most of people from some of those nations tend to be more physically active than many Americans.
The researchers had everyone’s body mass index (BMI). They measured activity and calorie burning for a week, but didn’t track whether people gained or lost weight.
It’s a fact that exercise did have an effect on how many calories people used, which is called energy expenditure, but the thing is that as people got more exercise the amount of calories burned didn’t increase dramatically. Those who had a moderate activity level burned a few more calories daily, on average around 200, versus the inactive people. But the most interesting part is that those people who exercised beyond the moderate activity level saw no effect of their extra effort as far as how many calories they burned.
The study didn’t refer to ”moderate” as in hours of activity, but Pontzer refers to moderate exercisers as those who are active ”but not serious athletes”, for ex. those who walk a couple miles a day or bike to work and back.
On the research the Pontzer’s team did find that those with higher body fat percentages actually burned more calories with exercise, and maybe it’s because of the fact that there is more fat to burn.
What do the findings say about the role of exercise in weight loss?
The survey didn’t focus only on this, but Pontzer says exercise ”can be part of a successful weight loss strategy. We need to think about exercise and diet as two different tools.”
“Exercise is good at lots of things, such as maintaining heart health,” he says. “Diet is going to be the better tool for managing your weight.”
Melanson says that the findings may show that the inactive lifestyle of many Americans hasn’t contributed as much to the nation’s obesity epidemic as much as public health officials believe, but according to him the study does not prove that, but simply adds information to the ongoing debate about why Americans are so overweight.
According to Melanson the survey is leaning more toward overeating, not under-exercising, to explain the current U.S. obesity epidemic.
Why is it that more exercise is not better? Do we hit a kind of plateau?
Yes, Pontzer says. “If you are more active, your body might be adapting,” he says. “We hit an energy expenditure plateau. It’s part of the reason your body adapts to your new exercise routine.” That may be why many find it so hard to lose weight, he says.
But, he believes, that there is such a thing as an exercise, a point at which workout benefits, including calories burned, peak, and is called “sweet spot”.
How do you find your ”sweet spot”?
The most important is to pay attention to your body, Pontzer says. You know you’re out of the sweet spot and overdoing it when you feel worn out constantly and you need more time to recover from exercise, he says. At that point, it’s time to work out less.
What’s the best take-home advice from this research?
Melanson says ”the public health message is not going to change one bit. Exercise does matter (for overall health), whether you lose weight or not.” And even if researchers eventually decide that diet plays a bigger role than exercise in weight control, the reality is what Melanson said previously.
Working out can contribute to brain and immune system health, and has lots of health perks, including stress reduction, diabetes prevention, blood pressure control, and boosting your mood to help with depression, experts say.
“This [study] says the first thing to do is diet and it won’t hurt to throw in exercise,” Pontzer says.