脫水會影響運動表現與傷害運動員的健康，因此復水對運動員而言是非常重要的。運動員的脫水可能是運動中流汗造成的，也可能是脫水減重或熱環境下運動未適當補充水分而造成的急性脫水；不同狀況下使用的復水溶液應有所不同。依據美國運動醫學會的建議，運動時間超過1 小時的運動員應適當飲用含有醣類5%-10%、鈉20-30 mEq/L、氯20-30 mEq/L、鉀2-5 mEq/L的運動飲料，以防止運動中脫水而降低運動表現。而世界衛生組織建議一種用於治療急性腹瀉引起脫水的口服復水溶液處方，其相較於運動飲料為低醣(13.5-20 g/L)、高電解質（鈉75-90 mEq/L、氯65-80 mEq/L、鉀20 mEq/L），對於已經發生急性脫水的運動員而言，口服復水溶液應該更能滿足人體在大量水分流失後的需求，使身體快速回復平衡的狀態。

Rehydration is crucial for athletes since the dehydration will decrease performance and causes adverse effect to health. Dehydration of athletes may be caused by sweating during exercise, weight reduction or exercising in hot environment without adequate supplementation of water. Application of rehydration fluid should be different depending on variance situations. The American College of Sport Medicine suggests that athlete should ingest sports drink containing 5%-10% of carbohydrate, 20-30 mEq/L of sodium, 20-30 mEq/L of chlorine, and 2-5 mEq/L of potassium when exercise is lasted more than one hour to prevent dehydration before performance is reduced. World Health Organization recommends an oral rehydration solution which contains less carbohydrate (13.5-20 g/L) and more electrolytes (75-90 mEq/L of sodium, 65-80 mEq/L of chlorine, and 20 mEq/L of potassium) to treat dehydration after acute diarrhea. The fluid could be more efficient in rehydration for dehydrated athletes.