While not the most exciting topic, proper hydration is incredibly important for anyone who’s active.
Fluids keep everything from your brain to your big toes functioning properly. Nutrients are transported by and dissolved in fluids… The sweat we use to cool body temperature is comprised of fluids… Metabolic waste products are excreted in fluids (1)… Quite simply, fluids – specifically, the water that they contain — are more essential than ANY other nutrient. We can survive without food for weeks, but perish after just a few days without water.
Our bodies are comprised of over 60% water. Concentrations in muscle tissues are even higher. So, it shouldn’t really come as much of a surprise that as little as a 2% reduction in body water can diminish performance by 10-20%! Imagine if there was an energy or protein bar that could almost instantly improve performance by up to 20%; the stores wouldn’t be able to keep that $#*! on the shelves.
Luckily, fluids are found pretty much everywhere. The most obvious source is water itself. But, other liquids like coffee, tea, sports drinks, juice, and soda pop are also quite hydrating (2). Foods such as fruits & vegetables, soups & stews, and cooked cereals like oatmeal contain lots of water, which counts towards your daily fluid intake.
How do you know if you’re drinking enough? Thirst and urine color can be unreliable predictors of fluid needs. By the time that you get thirsty, fluid losses through perspiration and respiration may already be great enough to impact performance. And urine color can be affected your diet as much as your hydration status. Anyone who has ever taken a high-potency multivitamin knows how these supplements turn your pee bright yellow.
Sweat rate is a more dependable way to gauge your fluid needs. To calculate your sweat rate, simply weigh yourself (sans clothing) before and after your workout. For each half-pound of weight loss, you should aim to drink 6-8 fl oz (177-236 mL) of water or sports drink to replace what you lost during that workout. If you regularly perform different types of workouts (e.g., weights only, weights + cardio, long-duration cardio, and CrossFit), you should check your sweat rate for each and rehydrate accordingly. You’re likely to sweat more during long-duration cardio than you will during a workout focused solely on resistance training.
Bottom Line: Don’t skimp on hydration. It may not be as exciting as the latest training technique, nutrition bar, or carb-controlled diet plan, but it’s every bit as important.
- Athletes that eat a high protein diet need even more fluids to keep the kidneys flushed
- It’s a common myth that caffeine-containing beverages like coffee, tea, energy drinks, and cola are dehydrating. While they may not be as hydrating as pure water, the net effect is still positive. Put another way, you don’t pee out more than you take in. In fact, the increase in urine output for caffeinated beverages is only marginally higher.