Do crusty white salt marks appear on your face and clothing when you work out? This can help determine if you are a salty sweater.
Sweat rate isn't directly related to sodium loss. You can be a heavy sweater and not necessarily lose a lot of sodium, and vice versa. But, no matter how much you sweat, you lose nutrients as well as water.
Sweat contains electrolytes: sodium, potassium, chloride and small amounts of minerals (iron, calcium, and magnesium). Of all these, sodium takes the biggest hit from sweat loss, so it's the most important to replace.
Most athletes lose about 500mg sodium per pound of sweat loss, and heavy, salty sweaters can lose more than 1500mg sodium each hour.
Because these electrolytes are essential to proper hydration, it’s important to also replace them after a workout. It’s difficult to measure exactly how much sodium and other electrolytes you lose in sweat, so you should contact a sports dietitian to determine the ideal amount you should be replacing.
Post-Workout Hydration Tips:
Once you know your sweat rate, you can develop a rehydration plan that’s tailored to your body.
For every pound of fluid (16oz) lost in exercise, you should consume 20oz to cover obligatory urine loss. The rehydration beverage should contain both sodium and simple carbs to accelerate reabsorption.
Products like Skratch Labs Hydration Mix and nuun drink tablets pack both electrolytes and carbs to help you replenish the other stuff you lose in sweat.
By Susan Kitchen. Susan is a Sports Certified Registered Dietitian, USA Triathlon Level II Endurance Coach, IRONMAN Certified Coach, published author and founder of Race Smart, a sports nutrition and coaching company.