Sweat doesn't isn't just moisture meant to cool your skin; it also contains salt. The salt can accumulate on your skin and clothing, making unattractive white stains on your shirt after sweating that can make you feel uncomfortable walking around after you exercise.
Salt stains on your clothes are normal in most cases, but take the proper precautions to replenish your body's salt levels during and after hard workouts. Stay hydrated and consider a sports drink containing salt during particularly difficult workouts.
All Sweat Isn't Created Equal
When you've been running on the treadmill for the same time as the person next to you but he is barely breaking a sweat, it doesn't mean he's in better shape. Not everyone sweats to the same degree, nor do people release the same amount of salt as they sweat.
The amount you sweat and the sweat composition is a result of many factors, including your genetics, the temperature and your metabolism. Some people never have to worry about salt on their clothing after exercising, while others battle the issue with every workout.
Problems With Salt Loss
If you have salt on your clothes after a workout, chances are you're losing a fair amount of salt in your sweat. During a short workout, this isn't such a problem -- consume a sports drink that includes sodium, and you should be fine.
Over an extended exercise period, such as running a marathon, problems can arise from salt loss. When you replenish your body with too much water and not enough salt — which can happen even when drinking sports drinks during the run — you could develop hyponatremia. This salt imbalance can cause cramping, nausea, confusion and seizures.
Hyponatremia can be dangerous, even deadly, if not treated quickly. Seek immediate medical attention if you show any symptoms of hyponatremia.
Salt Is a Good Thing
Although some people are on doctor-ordered salt-restricted diets, most people get plenty of salt through everyday foods to meet their needs during a typical workout. Processed foods include salt, but even foods such as eggs and cheese contribute to your sodium intake.
The Centers for Disease Control and Prevention recommends no more than 2,300 grams of sodium per day, and you typically lose about 500 milligrams of sodium in 1 pound of sweat. In a normal workout, you could lose a pound of sweat in about an hour. When exercising intensely in hot weather, that can climb to 2 pounds of sweat per hour and up to 1,100 milligrams of sweat per pound.
Salt Stains on Your Clothes
Salty sweat stains can easily ruin your workout clothes if not treated promptly. Soaking them in cold water until you're ready to wash them can keep the stains from setting in. Pre-treating the stains with a commercial stain remover also can help, or use household solutions such as baking soda, vinegar or lemon juice. Wash them with your normal detergent in warm water.