Sports drinks are great for replacing needed electrolytes and nutrients during a strenuous workout. Many athletes drink sports drinks to rehydrate after a strenuous workout. However, for the average person exercising, drinking a sports drink for every workout isn't necessary for good health.
Sports drinks are great for very strenuous workouts that last for 3 - 5 hours or more, like marathons, triathlons, etc. Drinking only water during these types of workouts can lead to hyponatremia (low blood sodium concentration.)
For regular exercise lasting 30 minutes to 1 hour, water will do the job just fine.
