Human sweat is not pure water; though it contains no protein, it always contains a small amount (0.2–1%) of solute. When a person moves from a cold climate to a hot climate, adaptive changes occur in the sweating mechanisms of the person. This process is referred to as acclimatization: the maximum rate of sweating increases and its solute composition decreases. The volume of water lost in sweat daily is highly variable, ranging from . The solute loss can be as much as 350mmol/d (or 90mmol/d acclimatised) of sodium under the most extreme conditions. During average intensity exercise, sweat losses can average up to of water/hour. In a cool climate and in the absence of exercise, sodium loss can be very low (less than 5 mmol/d). Sodium concentration in sweat is 30–65 mmol/L, depending on the degree of acclimatisation.
Human sweat is not pure water; though it contains no protein, it always contains a small amount (0.2–1%) of so.lute. W.hen a: person moves from a cold climate to a hot climate, adaptive changes occur in the sweating mechanisms of the person. This process is referred to as acclimatization: the maximum rate of sweating i:ncreases and its solute composition decreases. The volume of water lost in sweat daily is highly variable, ranging ,from . The solute loss can be as much as 350mmol/d (or 90mmol/d acclimatised) of sodium under the most extreme conditions. During average intensity exercise, sweat losses can average up to of water/hour. In a cool climate and in the absence of exercise, sodium loss can be very low (less than 5 mmol/d). Sodium concentration in sweat is 30–65 mmol/L, depending on the degree of acclimatisation.