Ask the experts: Sports drinks

Q: “I go to the gym. Do I need a sports drink during and/or after my workout?”

A: Senior nutritionist Rose Carr responds:

Probably not. If your workout is less than an hour long, or longer but at a low intensity, there’s little to be gained from drinking a sports drink over plain water from the tap. Four to eight per cent carbohydrate in a sports drink helps water absorption in the gut, and the sodium improves flavour and water absorption, as well as stimulating thirst so you drink more. Sports drinks are great for endurance sports or high intensity workouts, but can add unnecessary kilojoules and expense for shorter or less intense workouts.

Losing body water can cause headaches and affect concentration, so it’s important to get enough water (from various drinks as well as foods) to get the best out of your workout and working day. If you’re not sure how much fluid you need, there are two ways to monitor this. One is to check the colour of your urine: if it’s pale or almost clear, you’re getting enough fluid. However, if your urine is darker, you need more fluid. You can also weigh yourself before and after a workout. Losing one kilo during exercise is equivalent to losing nearly one litre of fluid through sweating which has not been replaced by drinking. (Note that a weight gain indicates over-hydration which is also not advised and potentially harmful). Remember that your fluid needs will vary depending on the intensity and length of your exercise and will change from winter to summer.