Now that summer's here, it's more important than ever to stay hydrated. Athletes and those who exercise every day need more water than the average individual. A muscle is comprised of 80% water and your body is 45% to 60% water.
Exercise generates more heat in your muscles. Intense, shorter duration activities like weight training can raise heat production 100 times what it would be at rest. During exercise, your body temperature and heart rate also increase. Eventually, the body is limited in transferring heat from the muscles to the skin surface.
It's important to drink water before, during and after exercise. Your athletic performance can suffer with as little as a 2% drop in body weight from fluid loss. Everyone is different, but the standard recommendation of 8 glasses of water a day was meant for inactive people. Athletes likely require more.
In addition to hydration, water also helps with nutrient absorption by transporting food through the digestive system. It's also absorbed into the muscle cells, which is important because carbohydrates can't be completely absorbed into muscle cells without an adequate supply of water.
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