Last month, my friend Lila started training for her first 5K. Sheād read somewhere that you need to drink 8 glasses of water during any workout, so she chugged a bottle before her run and kept sipping every 10 minutes. Halfway through, she felt bloated, got cramps, and had to stop. Turns out, sheād overhydratedāand the 8-glass rule she followed was a myth.
Is 8 Glasses Really the Magic Number?
The idea that everyone needs 8 glasses of water during workouts is a persistent myth. Itās not based on scientific evidence for athletes or casual exercisers. Your hydration needs depend on a bunch of factors: how much you sweat (some people sweat more than others), the weather (hot and humid days mean more fluid loss), the length and intensity of your workout, and even your body size.
2 Key Hydration Myths to Ditch
Letās break down two of the most common workout hydration myths and their truths:
| Myth | Truth | Why It Matters |
|---|---|---|
| You must drink 8 glasses of water during every workout. | Hydration needs are individualāaim for 4-8 ounces every 15-20 minutes during moderate exercise. | Overhydration can lead to cramps, nausea, or even hyponatremia (low sodium levels). |
| Only water counts for workout hydration. | Electrolyte-rich drinks (like sports drinks) are useful for workouts longer than 60 minutes. | Long workouts deplete sodium and other electrolytes, which water alone canāt replace. |
āThe best guide to hydration is your own body. If youāre thirsty, drink.ā ā Alberto Salazar, former marathon champion
Salazarās words ring true here. Instead of sticking to a rigid number, pay attention to your bodyās cues. Thirst is a reliable sign you need to drink, and the color of your urine (pale yellow is ideal) can also help you gauge hydration levels.
Common Q&A: Sports Drinks vs. Water
Q: Can I use sports drinks for all my workouts?
A: Not necessarily. For short, moderate workouts (like a 30-minute walk or yoga class), water is enough. Sports drinks are better for longer sessions (over 60 minutes) or intense activities (like running a half-marathon) where youāre losing a lot of sweat and electrolytes. They help replace sodium and carbs to keep your energy up.
Practical Hydration Tips for Workouts
- š§ Pre-hydrate: Drink 16-20 ounces of water 1-2 hours before your workout.
- š” Sip, donāt chug: Drinking too fast can cause stomach issues. Take small sips every 15-20 minutes.
- ā” Replenish post-workout: Drink 16-24 ounces of water (or a sports drink if needed) within an hour after your workout to replace lost fluids.
At the end of the day, hydration isnāt about following a strict ruleāitās about understanding your body and adjusting accordingly. Lila now drinks based on her thirst and the length of her runs, and she hasnāt had cramps since. So next time you hit the gym or the trails, forget the 8-glass myth and listen to what your body tells you.
