Philip J. Goscienski, M.D.
Do you really need to shell out several dollars per month on sports drinks? Not if you exercise lightly in cool weather. However, if you engage in moderately intense, prolonged activity on a hot, humid day, you will need what most sports drinks have to offer: replacement fluid, carbohydrate and salt. If your occupation involves exertion in hot weather the same guidelines apply.
Don't depend on a sensation of thirst to tell you that you need fluids. As we get older the thirst mechanism becomes unreliable. Drink at least a cup (8 ounces) before exercising, a few more ounces during a workout and another cup or two afterwards. There are no hard numbers here; your needs will vary with your size, the intensity and duration of your workout and the environmental temperature.
Activity burns calories that need to be replaced but unless you're running or walking a long distance there's no need for a sugary drink or snack. That before-exercise drink could be 8 ounces of orange juice, which contains about 115 calories, almost all from natural sugars. Sports drinks come with or without sugar. The latter usually rely on artificial sweeteners, something that many people prefer to avoid. If your exercise is hours long you'll need some carbohydrate along the way and the "-ade" brands provide it.
Have you ever noticed a salty taste to your skin after a sweaty workout? That's ordinary sodium and a signal that you need to replace it. The amount of sodium in sweat varies considerably from one person to another. Sports drinks contain about 200 milligrams of sodium per pint, which should be enough for a workout that lasts less than a couple of hours. Potassium is another important electrolyte but orange juice has several times as much as most sports drinks, another reason for making it your pre-workout beverage.
Resistance exercise builds muscle and it requires an intake of protein, best taken both before and after your weightlifting session. Except for competitive athletes or bodybuilders a workout routine should last no more than an hour. Unless the gym is beastly hot and humid you won't need a sports drink. Whether you get your protein in a shake or a steak it will have enough sodium to replace what you might lose.
Sports drinks fill the needs of those who exercise with intensity — an activity that could go a long way to solving the obesity problem.
Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at firstname.lastname@example.org.