Some athletes who do long, tough workouts like marathons or triathlons can end up with low sodium in their blood — a condition called exercise-associated hyponatremia — and it’s actually pretty common depending on the event.

Even if endurance runners take in a lot of salt, they can still develop low blood sodium if they drink too much water — it’s the overdrinking, not the salt intake, that’s the main problem.

Even if endurance runners take a lot of salt pills during long races, drinking too much water — like 10 liters — can still give them a dangerous condition called low blood sodium. Salt alone won’t protect you if you’re chugging way too much water.

If a runner gets low on salt during a long race, drinking a strong saltwater mix might help boost their sodium levels quickly before they get to a hospital.

Drinking too much fluid during long workouts can actually be dangerous — it can lead to a serious condition called low blood salt (hyponatremia), especially if you're gaining weight during a race because you're taking in more fluid than you're losing.

If endurance runners drink too much during long races, it can dilute their blood and cause dangerous low sodium levels — not just from losing salt, but from drinking too much. Cutting back on fluids in events over 4 hours could prevent this problem.