Exercise is an absolutely vital part of a healthy life. Exercise keeps your heart healthy, your muscles strong, your body stable and your mind vital. Most people would also think that exercise helps with weight loss; in fact, losing weight is often what motivates people to start an exercise program. In a new study, researchers set out to discover if exercise really does help with weight loss.
The researchers noted that people who start exercising often see a slowing in weight loss or even some weight gain after a few months. To see why this might be so, the researchers measured daily energy expenditure and activity levels using an accelerometer (similar to a Fitbit) for more than 300 men and women over a week.
They discovered a measurable effect of activity levels on energy expenditure, albeit it a weak link. When they dug deeper into the data, it emerged that the link only held true for subjects on the lower half of the daily activity spectrum. The data showed that people with moderate activity levels did burn about 840 more kilojoules a day than people who were sedentary. However, people who had above moderate activity levels did not burn any more kilojoules daily than people who exercised moderately.
The moderate level at which the weight loss stops would be achieved if you are walking around three kilometres a day, taking the stairs instead of the lift and trying to exercise a couple times a week. Beyond that, the researchers believe that your body adapts to higher activity levels and you don’t burn more kilojoules by exercising more. They found that the participants did actually continue to burn more and more “activity calories†as they exercised more, but their bodies compensated by burning fewer resting calories, which are used for carrying out basic biological functions.
So people going from a sedentary lifestyle to a moderately active one will probably see the most weight-loss benefit. For people who are already active, the researchers suggest trying new types of exercise. If you run a lot, try adding swimming or cycling to your exercise program, as the new muscle groups used will increase kilojoule burn.
None of this diminishes the need to exercise in order to be healthy but, if you really want to lose weight as well, then you need to also eat well and perhaps be smart about your exercise too.
