The current prescription to stay hydrated during your workout is to drink water when you’re thirsty.
But those instructions aren’t always clear because too many of us try to satisfy thirst with food instead of water. So nutritionists recommend you drink half your body weight in ounces every day. That means if you weigh 150 pounds, aim for 75 ounces of water a day. Drink more when it’s hotter or if, after you finish a run, you have salt streaks on your skin.
How do you know if you’re drinking enough water? Your urine will be the color of pale lemonade. Clear urine means you’re drinking too much water. If it’s the color of apple juice, drink more. Here’s another formula: Weigh yourself naked before your run and again after. Keep track of how much fluid you consume during the run and add it to the amount of weight you lose. For every pound of body weight you lose, drink an additional 16 ounces of fluid.
How do you know if you need to drink more than water? Sometimes you need the nutrients found in sports: electrolytes, such as sodium and potassium, which you need for proper nerve and muscle function (and which are lost through sweat), and carbs for energy. Consider reaching for a sports drink if:
- You run for more than an hour. If you run for an hour or more, refuel on the road with 30 to 60 grams of carbs per hour. If eating on the run messes with your stomach, sports drinks are an easy alternative.
It’s hot and humid outside. When you sweat, you lose electrolytes. Sports drinks will help you restore electrolytes and hold onto fluids, so you can keep running.
- You’re a salty sweater. If you notice white streaks on your skin after your run, it means you’ve lost a lot of sodium through sweat. You’ve probably also lost potassium, magnesium and calcium. Sports drinks will help you replenish these.
- You’re doing two workouts close together. If you’re running twice in less than 15 hours or doing two workouts in one day, rehydration is key to helping you power through the next workout. Complete rehydration means replacing both fluid and electrolyte losses. After your run, drink 24 ounces of fluid for every pound of weight lost. Water is fine if you’re also eating salty, solid foods. A protein shake with electrolytes will provide protein, carbs and fluids for rehydration and recovery. But if you can tolerate only fluids and don’t have time to digest a protein shake before your next workout, grab a sports drink.