Sports drinks have so many calories they may cancel out the benefits of exercise, the Telegraph reported.

At nearly 300 calories, many popular brands contain virtually the same amount of calories as a Mars Bar, and would take about a half hour of jogging to burn off.

Drinking sports beverages “could completely counteract exercising more, playing football more, going to the gym more,” for those hoping to lose weight, said Dr. Matthew Thompson from the Oxford Centre for Evidence Based Medicine.

While some drinks are lower-calorie than others, most people should stick to water instead, the researchers recommended.

A spokesperson from the British Soft Drinks Association told the Telegraph that sports drinks help people participating in physical activities perform better and recover more quickly.

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