How Salt in Drinks Affects Your Body During Long Bike Rides
Sodium replacement and fluid shifts during prolonged exercise in humans
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
When cyclists drink fluids with more salt during a long ride, their bodies hold onto more water in the right places and pee less. But the salt level in their blood stays the same no matter how much salt they drink.
Surprising Findings
Plasma osmolality didn’t change even with vastly different sodium intakes.
Most people assume drinking salt raises blood salt levels, but here, even 100 mEq/L of sodium didn’t budge it—showing how tightly the body regulates this.
Practical Takeaways
Include sodium in your drink during prolonged exercise (e.g., 4+ hours) to help maintain blood volume and reduce unnecessary fluid loss through urine.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
When cyclists drink fluids with more salt during a long ride, their bodies hold onto more water in the right places and pee less. But the salt level in their blood stays the same no matter how much salt they drink.
Surprising Findings
Plasma osmolality didn’t change even with vastly different sodium intakes.
Most people assume drinking salt raises blood salt levels, but here, even 100 mEq/L of sodium didn’t budge it—showing how tightly the body regulates this.
Practical Takeaways
Include sodium in your drink during prolonged exercise (e.g., 4+ hours) to help maintain blood volume and reduce unnecessary fluid loss through urine.
Publication
Journal
European Journal of Applied Physiology
Year
2001
Authors
B. Sanders, T. D. Noakes, S. Dennis
Related Content
Claims (4)
If cyclists drink the same amount of fluid during a 4-hour ride, it doesn’t matter how much salt is in the drink — their blood salt levels stay steady even if their body handles water and salt differently.
If endurance cyclists drink fluids with sodium during long rides, they pee less and keep more fluid in their bloodstream, which helps prevent dehydration—even though the salt level in their blood stays the same.
If you're biking for a long time and drink fluids with a lot of salt, your body holds onto more fluid outside your cells. But if you drink fluids with almost no salt, you actually lose fluid from that same space — even if you're sweating the same amount.
When athletes sweat a lot during tough workouts in the heat, they can lose a surprising amount of salt—up to more than a teaspoon of salt every hour.