Sodium and salt for athletic performance
Sodium and salt play a key role in the body's functioning during exercise, helping to maintain fluid balance and cognitive function, among other things. When sweat losses increase over time, and thus salt and sodium are lost, it is crucial that these are adequately replaced.
Importance of sodium in competition
A 2015 study1 of a middle-distance triathlon found that athletes who adequately replaced sodium lost through sweat finished an average of 26 minutes faster than those who did not. While this performance benefit cannot be generalized, it exemplifies the potential impact that a proper hydration strategy can have on performance.
Athletic performance
Salt and sodium play an important role in athletic performance, among other reasons:
1. Electrolytes and fluid balance: Sodium is an essential electrolyte that helps maintain body fluid balance. During exercise, the body loses not only water but also electrolytes, primarily sodium, through sweat. A constant sodium level is crucial to promote hydration and maintain fluid balance in the body.
2. Muscle contraction: Sodium is important for the function of muscle cells. It is involved in various functions necessary for muscle contraction. A sodium deficiency can lead to muscle cramps and reduced performance.
3. Blood pressure regulation: Sodium plays a role in blood pressure regulation. Stable blood pressure is important to ensure optimal blood flow during exercise and to ensure the supply of oxygen and nutrients (e.g., carbohydrates) to the muscles.
4. Energy production: Sodium is involved in various biochemical processes in the body that contribute to energy production. Adequate intake can therefore also support endurance and performance during strenuous workouts.
5. Avoid hyponatremia: During intense and prolonged exercise, especially in hot weather, hyponatremia can occur when blood sodium levels become too low. This can lead to symptoms such as nausea, headaches, and, in severe cases, confusion or seizures.
Individual sodium loss in sweat
Sweating is the main cause of sodium and fluid loss. Therefore, those who exercise regularly and thus sweat have different sodium replacement needs compared to the normal population. Furthermore, the amount of sodium in our sweat is individual and can vary greatly from person to person. We see athletes who lose only 180 mg of sodium per liter of sweat as well as those who sweat out 2600 mg of sodium per liter. For this reason, blanket recommendations for
Individual sodium intake makes little sense. The sodium concentration in sweat is largely genetically determined and varies only slightly,2 depending on training status, for example. This means it can be easily determined with a sweat test .
Summary
It's important to ensure adequate intake of sodium and other electrolytes during exercise and sweating—especially during long, intense, and strenuous workouts—to support performance, recovery, and health. Ideally, sodium and salt intake should be individually tailored based on both genetic factors (sodium loss per liter of sweat) and athletic factors (sweat volume).
The Sweat Test is an ideal way to easily measure your individual sodium concentration in sweat and receive personalized advice on how to implement this in practice. For ambitious athletes, we recommend repeating the test once a year, for example, before the start of the competition season.
Source:1: Scandinavian Journal of Medicine & Science in Sports, 2015 https://www.sciencedaily.com/releases/2015/03/150304075220.htm
2: Sweating Rate and Sweat Sodium Concentration in Athletes: A Review of Methodology and Intra/Interindividual Variability; Lindsay B Baker (2017)