With so much concern over the fuel we put into our bodies for optimum performance or weight loss, we often overlook an extremely important aspect to an effective workout program: hydration.
Improper hydration can impair performance whether you are training for a race, or sweating it out in a spin class. In addition to poor perforamnce, dehyration can have serious consequences if electrolytes become imbalanced. For some who are trying to lose weight, thirst can even be misconstrued for hunger signals and cause you to overeat.
So how much fluid should you be drinking? It depends on how much you sweat and how long you exercised. But here are some general guidelines to keep in mind:
Before exercising: 5 to 7 mL/kg of body weight (2 to 3 mg/lb) four hours before activity. For a 120 pound woman this is about 1 and 1/2 glasses (8 ounces) of water. If you are headed to the gym after work, and not preparing for an endurance event, sipping water throughout the day should be sufficient.
After exercising: 24 ounces for each pound lost. This is about 3 glasses of water. If you weigh yourself before and after a workout and notice a loss of two pounds immediately, this is likely due to a loss of water weight. By drinking water to rehydrate yourself you will not negate any weight loss efforts that are a result of fat loss. Instead you will be able to recover more quickly and be more likely to work just as hard at your next workout.
Sports drinks with electrolyte replacements are necessary in cases of endurance exercise when an individual is exercising longer than an hour, or in hot temperatures, to provide fuel for the muscles in the form of glucose (sugar) and decrease dehydration risks. For the average person exercising at the gym under normal conditions, rehydrating with water is a better choice to avoid unnecessary caloric intake. Sports drinks purposely have added calories from sugar, as well as added electrolytes that you may not need. Just make sure you are properly fueling with food too (read here for more information).