Hi there, Fall is coming, which means marathon training is ramping up. High mileage plus high temperatures means your sodium needs probably ramp up, too. Sodium helps you maintain blood volume. Lose too much sodium without replacing it, and blood volume falls. Your heart works harder. Cooling becomes less efficient. You run the risk of nausea and GI distress. Of course, sodium losses (and therefore needs) vary from person to person. There's no one-size-fits-all prescription, but running coach Bailey Lasko and LMNT partner Zach Bitter recommend using this sodium protocol as a starting point: Start with a baseline. About 500 mg of electrolytes per hour (half a stick pack of LMNT) in normal conditions, increasing to about 900 mg (a full stick pack) for hotter or longer efforts. Estimate your sweat losses. Weigh yourself before and after an hour of training without drinking anything. One kilogram (2.2 lb) of weight loss is roughly equal to one liter of fluid lost. Check for signs you may be a salty sweater. White salt deposits on your clothing, a salty taste on your skin, or stinging eyes all point to higher sodium losses. Adjust for heat. In hot conditions, aim for roughly 1.5 to 2 times more sodium than you'd need in cooler weather. Adjust for diet. Low-carb or keto athletes often need more sodium, especially early on, since lower insulin causes the body to excrete more sodium in urine. Monitor and iterate. If a hot long run leaves you wrecked, lightheaded, or needing hours to rehydrate, your sodium target might be too low.
That's the framework. In today's article, we go deeper into the science behind it, including: Why elite ultrarunner Zach Bitter nearly passed out at the finish line despite drinking water all day How sodium helps your gut absorb carbs during long efforts, not just fluid Why hyponatremia, a dangerous sodium crash, can affect up to 22% of marathon runners
It may be hot out there, but getting your electrolytes dialed in now can help you cross the finish line feeling stronger and recover faster. Stay Salty,
Robb and the LMNT Team |
