“Your ability to perform athletically can decline with a very small amount of dehydration. “Just losing 2% of your body weight in fluid can decrease performance by up to 25%.”
Whether you’re an elite athlete or a weekend warrior, drinking water is essential if you want to get the most out of your workout and feel good while you’re doing it.
If you are well-hydrated you will feel stronger and can work out longer and more effectively. “The heart does not have to work as hard to pump blood to the body, and oxygen and nutrients can be transported more efficiently to the muscles you’re working during exercise,”
But research has found that even experienced athletes don’t do a very good job at estimating their fluid needs.
So how much water should you drink before, during, and after a workout? First, make sure you’re well hydrated to begin with. Drink fluids throughout the day before you exercise. Then follow this formula from Melton:
You may need to drink more if you’re sweating heavily, especially if you’re exercising outdoors in very hot weather.
When you’re working out, you’re more likely to be losing water, both through your breath and through sweat, If you start out dehydrated, you won’t get a good workout. You’ll get dizzy, lethargic, your muscles won’t work as well, you won’t feel as sharp mentally, and you’ll get cramps sooner.
That’s because water helps your body to exercise efficiently. It lubricates your entire body — without it, you’re like the Tin Man without his oil. It’s a vital part of the many chemical reactions in the body. “If these reactions slow down then tissues heal slower, muscle recovery is slower and the body is not functioning at 100% efficiency,” says Trent Nessler, PT, DPT, MPT, managing director of Baptist Sports Medicine in Nashville.