Thousands of gym-goers who buy energy sports drinks are wasting their money, an expert said yesterday.
While the drinks may be suitable for people training for events such as marathons, many exercisers just end up consuming lots of extra calories.
Nick Hudson, national fitness manager for Virgin Active, said those doing workouts of less than two hours do not really benefit from the drinks.
“Many people drink energy drinks in the belief they will give them more energy to exercise harder,” he said.
“But many of these drinks are simply ‘calorie drinks’ and drinking them means you’ll actually have to train longer or harder to shift the calories that you take in from the drink itself.
“They’re certainly useful for people who compete in very long distance events where they’ll be exercising in excess of two hours.
“Your body is generally thought to be able to store enough glycogen (a form of glucose) to last roughly two hours and marathon runners swear by them.
“But those doing shorter, more intense workouts don’t really benefit physiologically.”
Mr Hudson said people trying to lose weight should avoid the drinks altogether, or opt for a low-calorie version.
However, it is important to avoid dehydration, he added.
“You certainly should be well hydrated to exercise so choose water or a zero or low-calorie exercise drink instead of a high calorie one.
“From a taste perspective, if someone has become conditioned to dislike the taste of water then it’s certainly better to drink these drinks than be dehydrated.”
Most energy drinks contain some form of carbohydrate to provide a quick source of fuel, and sodium, which helps to maintain fluid balance in the body.
Smaller amounts of other electrolytes, such as potassium and chloride, which are lost in sweat, may also be included.
Mr Hudson said people who run or train over long distances will need to replace lost electrolytes in the system, and these drinks can help in those situations.
“After a training session is also a good idea – there’s no doubt that after very long distance events you need to replace electrolytes,” he said.
“But just remember that water and food with salt will really do the same thing.”
Research on the impact of energy drinks in adults has produced mixed results, with some finding no effect on performance and others finding some benefit.