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The next time you see a climber hauling a gallon jug to the crag, consider this: Depending on how long he’s out, drinking that much water could cause more harm than good. While most of us worry about dehydration, overhydration can lead to a throbbing headache, nausea, muscle spasms, cramps, and in a worst-case scenario, brain swelling or a coma. Plus, a gallon of water weighs more than 8 pounds. Preparing your climbing gear for a day at the crag isn’t guesswork, and calculating the amount of fluids you need shouldn’t be either. To keep your head from swimming over the art of proper hydration, read the tips below on how to maintain optimal hydration.
Water and Electrolytes
Water consumption and electrolytes go hand in hand when discussing hydration. Electrolytes, the body’s critical salts and minerals, regulate muscle contraction. Operating under a codependent relationship, electrolytes move between cells through plasma, which is primarily composed of water. Riding on this fluid, potassium and sodium are exchanged between cell membranes to give muscles an electrical charge, meaning a contraction. This electrolyte-induced jolt happens billions of times during exercise. However, just as water carries electrolytes between cells, it also carries them straight out of the body in the form of sweat.
Dehydration, or hypernatremia, happens when the body is oversaturated with electrolytes but lacks adequate water. Overhydration, or hyponatremia, occurs when the ratio of electrolytes is diluted by excess water. Both conditions can cause physical and mental impairment. Rehydration following exercise should include replenishing lost stores of water as well as electrolytes: sodium, potassium, chloride, calcium, magnesium, bicarbonate, and hydrogen phosphate.
Hydration for Climbers
A variety of conditions affect how you should approach hydration. Is your natural sweat level heavy or light? Is it hot outside? Humid? How many hours will you be climbing? What have you had to drink and eat so far that day? The simplest way to gauge hydration is urine tint, with pale yellow meaning you’re good. If your urine is closer to the highlighter-yellow color of this page, then drink some water.
Observing weight fluctuations on long climbing days can help measure hydration. If your session is going to last a couple hours, hop on the scale before and after climbing. An increase in weight by 2.5 percent or more signifies overhydration. In this case, replenishing electrolyte stores is most important, so eat a snack with salts and sugars. Continuing to consume fluids in this state (hyponatremia) can have serious consequences, particularly when blood sodium levels dip below a certain point (135mmol/L).
Conversely, dehydration might be an issue with a loss of 1 to 2 percent in body weight; losing more than 3 percent is very dangerous. The risk of tearing or pulling a muscle increases when dehydrated, and muscle recovery is severely hindered. Dehydration can result in heat exhaustion or heat stroke, regardless of the ambient temperature. If the body cannot produce sweat to cool itself, you will overheat. To properly hydrate, replace electrolytes while drinking water. Know the basic tenets of an electrolyte drink: water, salt, and sugar. As a rule for determining the baseline amount of water to drink in a day, divide your body weight in half to calculate the number of ounces needed at rest. Alcohol consumption, strenuous exercise, and hot weather require more water.
160 lb. Male Climber:
Baseline H2O requirement: 160/2 = 80 oz.
+2 hr. training = 16 oz.
+16 oz. beer = 8 oz.
Total H2O requirement: 104 oz.
125 lb. Female Climber:
Baseline H2O requirement: 125/2 = 62.5 oz.
+2 hr. training = 16 oz.
+12 oz. Red Bull = 12 oz.
+30 min. running = 4 oz.
Total H2O requirement: 94.5 oz.
In commercial recovery mixes, look for options without artificial dyes or sweeteners (like Skratch Labs and Vega Sports). Naturally sourced sugars like coconut palm nectar, stevia, and tapioca starch are OK because carbohydrates are essential during recovery. Finishing a workout with an electrolyte-rich snack is another alternative. Trail mixes with salted nuts and dried fruit (like raisins) provide sodium as well as potassium. Other electrolyte-rich foods include avocados, salad greens, sweet potatoes, yogurt, whole grains, lentils, dried beans, and most vegetables. Or consider making your own electrolyte drink with this recipe:
- 6 oz. fresh citrus juice (lemon, lime, orange, or grapefruit)
- 1—2 oz. honey, sugar, or natural sweetener
- ½ tsp. salt
- 16 oz. water