For some time, scientists have been puzzled - and exercisers frustrated - by the general ineffectiveness of exercise as a weight-loss strategy. According to multiple studies and anecdotes, most people who start exercising do not lose as much weight as would be expected, given their increased energy expenditure. Some people add pounds despite burning hundreds of calories during workouts.
So researchers turned to psychology and the possible effect that calling exercise by any other name might have on people's subsequent diets. The researchers first recruited 56 healthy, adult women, the majority of them overweight. The women were given maps detailing the same one-mile outdoor course and told that they would spend the next half-hour walking there, with lunch to follow.
Half of the women were told that their walk was meant to be exercise, and they were encouraged to view it as such, monitoring their exertion throughout. The other women were told that their 30-minute outing would be a walk purely for pleasure; they would be listening to music through headphones and rating the sound quality, but mostly the researchers wanted them to enjoy themselves.
Those women who'd been formally exercising reported feeling more fatigued and grumpy than the other women, although the two groups' estimates of mileage and calories burned were almost identical. More telling, when the women sat down to a pasta lunch, with water or sugary soda to drink, and applesauce or chocolate pudding for dessert, the women in the exercise group loaded up on the soda and pudding, consuming significantly more calories from these sweets than the women who’d thought that they were walking for pleasure.
Source material from New York Times