Running, cycling, gym, hiking and team sport
Workout Hydration Calculator
Plan around the workout you are actually doing—not a generic activity label—and keep both underdrinking and overdrinking in view.
Before, during and after
Build your workout plan
Use a measured sweat rate when available. Otherwise the planner shows a clearly labelled conservative estimate.
Complete the workout details, then build a practical timeline.
Safety: these estimates are general guidance, not medical advice. Never drink beyond measured losses or to the point of weight gain. Excessive intake can contribute to hyponatraemia. People with kidney, heart or liver conditions, pregnancy, or medicines affecting fluid balance should follow personal clinical advice.
How the workout estimate works
When you provide a measured sweat rate, the calculator uses a bounded fraction of observed loss as the during-workout range. When you do not know it, activity, intensity, body size, temperature and humidity create a conservative estimate that is clearly labelled.
Short easy sessions in mild conditions are treated differently from long or hot sessions. The result is a starting plan to rehearse, not a requirement to finish every drink.
Keep the plan practical
Match the range to actual bottles, fountains, breaks or aid stations. Review what remained afterwards and repeat a sweat-rate test when season, clothing, intensity or environment changes.
Heat safety also involves pace, shade, clothing, cooling and acclimatisation. More fluid cannot make an unsafe session safe.
Workout hydration questions
How much water should I drink while running?
Use duration, weather, intensity, access, thirst and—when available—a sweat rate measured in similar conditions. A flexible range is safer and more useful than one universal running number.
Should I drink during a 30-minute workout?
Often not. For an easy short workout in mild conditions, starting normally hydrated and drinking afterwards may be sufficient. Keep fluid accessible when conditions or personal needs differ.
How much should I drink before exercise?
The planner uses body weight to create a bounded 2–4 hour range. It is intended for gradual preparation when needed, not last-minute water loading.
How much water should I drink after exercise?
Recovery depends on measured or estimated loss, what you drank during exercise, food and the time before your next session. Replace larger losses gradually.
Can you drink too much water during exercise?
Yes. Drinking beyond losses can cause body-mass gain and contribute to exercise-associated hyponatraemia. Sodium products do not make excessive drinking safe.