By the time you feel thirsty during a workout, mild dehydration may have already set in — the body typically signals thirst once fluid loss reaches around 1-2% of body weight, which can already cause a noticeable drop in performance. So what's the right amount, and when should you actually drink?
General Rules for Before, During, and After Training
Drinking about 400-600 ml of water 2-3 hours before training helps start the session well hydrated. During training, a common guideline is 150-250 ml every 15-20 minutes, though this can increase in hot weather or with heavy sweating. After training, it's recommended to drink around 1.5 liters of water for every kilogram of body weight lost, a ratio meant to make up not just for fluid lost through sweat but for ongoing loss through urine as well.
Is Water Alone Enough, or Do You Need Electrolytes?
For moderate-intensity sessions under 60 minutes, plain water is usually sufficient. But for workouts lasting over an hour with heavy sweating, replacing electrolytes like sodium and potassium becomes important — otherwise cramping and performance drops can occur. Electrolyte drinks can help in these cases, but they're generally unnecessary for light daily training; in fact, drinking sugary electrolyte beverages unnecessarily can add extra, unneeded calories.
Can Drinking Too Much Water Also Be a Risk?
A lesser-known risk around water intake is a condition called "hyponatremia," where blood sodium levels drop to a dangerous level due to overhydration; this typically occurs in long endurance events like marathons, when athletes keep forcing themselves to drink water even without feeling thirsty. That's why "the more water the better" is the wrong approach; listening to the body's thirst signals is generally safer than rigidly following a predetermined water-intake schedule.
3 Practical Tips for Proper Hydration
- Don't Wait to Feel Thirsty: By the time thirst kicks in, the body is already mildly dehydrated.
- Watch Your Urine Color: A light yellow color is generally a sign of good hydration.
- Don't Overdo It: Drinking excessive amounts of water in a short time can also throw off sodium balance.
