"The Happy Mountaineer Always Pisses Clear…"
The Happy Mountaineer Always Pisses Clear
by Kelly Cordes
The long days of summer provide plenty of bang for your climbing buck, and the best way to ensure that you'll climb well all day is by staying hydrated. It may seem simple --- just drink --- but there's a bit more to it.
No one is immune Everyone has had a partner who insists that he doesn't see much effect from dehydration ("I just don't need that much water," he'll say, passing on the water break for the fourth time that day). In fact, few things hinder performance as dramatically as dehydration. Even slight dehydration can impair aerobic endurance (think long climbing days, such as alpine routes or long rock climbs), primarily by reducing blood plasma volume. Problems include an increased heart rate, core body temperature and greater perceived effort at any given level of exercise.
In one study, when subjects dehydrated 1.9% of their body mass (2.8 lbs. for a 150-pound climber), a 22% decline in exercise endurance resulted. At 4.3% dehydration, the decline was a dramatic 48%. Just going cragging? Another study showed that dehydrated, fatigued athletes showed significantly reduced skill performance and coordination compared with athletes who were equally fatigued but hydrated.
Drink early, drink often. The human thirst mechanism is well known to be inadequate during exercise --- wait till you're thirsty, and you're already in the hole. Since gastric emptying (the rate at which fluids leave the stomach to be absorbed) is impaired when the body is dehydrated, it's crucial to drink early and often throughout the day.
You are most likely to dehydrate when drinking becomes a hassle (i.e., stopping to dig out a water bottle from your pack), so make sure your liquid is readily available. On long approaches and moderate all-day routes, wearing a hydration system will practically guarantee greater fluid intake. The added weight is easily offset by the performance benefits, and on harder multi-pitch climbs, the second can wear the hydration pack and sip while belaying.
Another important factor in staying hydrated is to make sure that your beverage is tasty. Sport drinks are your best bet, because they taste good and promote fluid retention. These drinks have the added bonus of supplying easily absorbed carbohydrates, which help maintain energy stores. Avoid drinks with fructose as their sole sugar source, such as fruit juices, because fructose absorbs slowly.
Individuals vary greatly in their fluid volume tolerance during exercise --- experiment with how much liquid is right for you, as feeling waterlogged isn't pleasant. Drink enough to maintain clear urine output, and strive to weigh about the same at the end of the day as you did at the start (true weight loss doesn't happen in a day, but you can easily drop five pounds or more from dehydration). Avoid taking in too many calories at once (i.e., sports drink, energy bar and snacks at the same time), which also hinders fluid absorption. Instead, nibble and sip continuously.
Rehydrating Hydration is largely a function of the human body's ability to maintain a balance between fluid and electrolytes (when dehydrated, sodium is the most important electrolyte to replenish). Once the body becomes dehydrated, fluids without sodium, like water, are not a good means of rehydrating because they throw off the balance. Several studies have shown that when dehydrated subjects drink beverages containing sodium, urine output is significantly lower and blood volume significantly greater than when drinking the same amount of plain water. Thanks to the sodium, the body retains a greater relative portion of the ingested fluid.
Most sports drinks have the right amount of sodium, while Kool-Aid, plain water and soda do not. The differences in fluid restoration rates are most pronounced during the initial six hours following dehydration.
Most foods also contain sodium and electrolytes, which helps --- just be sure to down plenty of water with them.
Kelly Cordes' exercise physiology master's thesis at the University of Montana dealt with hydration and thermoregulation.
Sports drinks are effective because they are quick sources of sugar and electrolytes. The sugar is important in maintaining blood glucose levels during prolonged exercise. Granulated sugar (sucrose) works great, as do maltodextrin and glucose (dextrose or corn sugar). Avoid fructose as your primary sugar source because its slow absorption may upset your stomach if taken in large quantities. For electrolytes, unless a person is severely dehydrated and isn't eating (we typically get enough electrolytes from our meals), sodium is the most important one because it promotes effective fluid retention, maintaining blood volume. Warning: excessive sodium and sugar concentration above 8% can impair fluid absorption.
Commercially available sports drinks aren't rocket science. For less than what you'd pay for a packet of Ramen, you can produce your own carbohydrate-electrolyte solution of about 7% sugar.
1 liter water
1/3 cup sugar
1/4 tsp. table salt (sodium-chloride)
1 packet of unsweetened Kool-Aid mix (add to taste)
Note: The weight of sugar divided by the volume of water will give you the concentration. Metric makes it easy: 1 Liter (33.8oz) = 100 ml; 1/3 cup sugar = 66 grams, or 6.6% sugar.