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Even if it doesn’t show up as a clear result in small studies, salty supplements might still make endurance cyclists feel thirstier during long rides in cool weather — possibly because salt affects how the body senses thirst.
Taking sodium supplements during a long bike ride in cool weather doesn’t really change your body’s sodium levels if you're already drinking fluids whenever you feel like it.
Endurance cyclists who take in 700 mg of sodium per hour during a 3-hour ride in cool weather tend to drink about 160 mL more fluid each hour than those who don’t — probably because the salt affects how thirsty they feel.
If elite cyclists drink as much as they want during a 3-hour ride in cool weather, taking in 700 mg of sodium per hour helps keep their blood fluid levels stable—or even slightly increases them—while skipping it leads to a small drop.
Taking sodium pills while cycling doesn't seem to make well-trained cyclists faster during a 72 km ride in cool weather — they finish just as quickly with or without it.
When these special mice have high blood pressure, their bodies seem to react by saving water — they drink more, their kidneys change how they handle water, and blood flow to the skin drops, possibly because their cells are losing water.
Mice given a certain hormone and baking soda don't get high blood pressure from too much salt because their cells swap potassium for sodium to stay hydrated — but mice given regular salt don't do this and their cells dry out.
In mice, losing potassium and water inside their cells happens before their blood pressure goes up — and this might actually help cause the high blood pressure, even if salt isn't building up at first.
If trained cyclists drink when they're thirsty during a 3-hour ride in cool weather, they can keep their sodium levels safe — even if they don't take extra sodium.
Taking sodium supplements while cycling for 3 hours in cool weather doesn’t stop your blood sodium from dropping slightly — and it’s no different than taking a fake pill. Nobody in either group had dangerously low sodium levels.
If you drink a sports drink with 700 mg of sodium every hour while cycling 72 km in cool weather, your blood volume might go up a little bit because the salt pulls water into your bloodstream from your cells.
If you're cycling for 3 hours in cool weather and take 700 mg of sodium every hour, you'll drink about 160 mL more fluids each hour without feeling any thirstier, because the salt may trigger a natural urge to drink.
Taking 700 mg of sodium every hour during a long bike ride in cool weather doesn’t make well-trained cyclists finish faster — they perform about the same as those taking a fake pill.
If healthy adults eat the typical high amount of salt found in processed foods, their body shows lower levels of important proteins that help control blood pressure and fight inflammation — compared to eating almost no salt at all.
Eating very little salt might raise levels of certain proteins in your blood that are linked to inflammation and blood pressure control, compared to eating a lot of salt—especially in people with normal blood pressure.
Eating a lot of salt—like most people do today—might raise levels of certain proteins in your blood that are linked to heart and blood vessel damage, compared to eating very little salt like people did long ago.
Ultramarathon runners who take sodium supplements during long races in extreme heat keep more of their body weight, but those who skip the supplements might actually stay better hydrated, according to the researchers.
Ultramarathon runners who took more sodium during a super long, super hot race tended to lose less body weight — the more sodium they took, the less weight they lost.
Ultramarathon runners who drank only when thirsty and skipped salt pills during a long, hot race lost about 3.4% of their body weight — and experts say that’s still a safe level of hydration.
Endurance runners in a super long, hot race who took sodium supplements every part of the way lost less body weight during the race than those who didn’t take any.
If fit guys sweat a lot for 3 hours in the heat and drink lots of fluid, a sports drink with more salt (60 mmol/L) helps keep their blood sodium up, while a low-salt version (21 mmol/L) causes it to drop — and the difference is clear.
When fit guys bike for 3 hours in the heat and drink about a liter of fluid per hour, they lose a little body weight — around half a percent. They might lose slightly less if their drink has more salt, but the difference isn’t strong enough to be sure it’s not just chance.
If fit guys sweat hard in the heat for about 3 hours and drink a lot of fluid, a sports drink with more salt (60 mmol/L) keeps their blood volume stable, but a low-salt version (21 mmol/L) causes their blood volume to drop by about 2%.
If fit guys bike hard in the heat and drink a lot, a sports drink with more sodium keeps their blood sodium steady, but one with less sodium causes it to drop a bit on average.