Caffeine. Beer. No water. Resort skiers and riders are notorious for becoming dehydrated on the slopes. But dehydration can affect performance. 

“Most people don’t drink while skiing, and just grab a sip at a water fountain, but that’s not drinking,” said John Seifert, associate professor in the Movement Science Lab at Montana State University. The exercise physiologist has been studying hydration in skiers for two decades. 

Over the past couple years, Seifert teamed up with Doug Wales from Bridger Bowl to study hydration behavior with recreational skiers. They discovered some surprising facts. 

“The vast majority of skiers show up in the morning dehydrated,” Seifert said. “They start the ski day dehydrated, having drunk tea or coffee. That’s one foot already in the hole.”

Hydration Story

Tea and coffee cause dehydration, yet many skiers start the day that way. Photo by Becky Lomax.  

Dehydration behavior usually continues during the day. Seifert points out that skiers lose water through normal breathing and sweating, but most fail to replenish fluids while skiing. Cold temperatures and altitude inhibit the desire to drink, and many skiers shun drinking to avoid taking bathroom breaks.

One mid-day study at Bridger got 130 skiers, ages 18-82, to complete a hydration questionnaire and contribute urine samples. Less than 10 percent of the skiers reported drinking while skiing. Analysis of the samples revealed than most were extremely dehydrated. 

“Ironically, a lot of people were carrying backpacks, but weren’t necessarily drinking,” Seifert notes. “For some people, the urine samples looked like orange juice.” 

One easy way to check your hydration level is to look at urine color. The clearer it is, the more hydrated you are. The darker yellow it is, the more dehydrated you are. 

Hydration Story

Urine samples show varying levels of dehydration. Photo by John Seifert. 

Seifert’s studies have shown that dehydration affects the ability of the body to cope. Dehydration can cut blood flow to muscles, which can cause them to be less productive. 

“If dehydrated, the heart must work harder to pump the same amount of blood,” Seifert explains. “The heart rate can go up 10-15 beats per minute just sitting on a chairlift.”

Not only will muscles lose the ability to remove waste products, but the body can also lose its ability to regulate temperature. When dehydrated, the body doesn’t push blood to the fingers and toes, hence cold extremities when sitting on a chairlift. 

“Feeling cold can set in quickly, in a matter of minutes,” Seifert said.

Hydration Story

Seiffert and Wales study has revealed much about skiing and hydration. Image Courtesy of John Seifert. 

Dehydration can diminish performance, including the number of runs you can ski. One three-hour study at Snowbird revealed a striking difference between skiers who drank sports drinks and those who didn’t drink while skiing. In the final hour, those using sports drinks averaged nearly four runs while those who did not drink averaged 2.5 runs. 

Unfortunately, waiting until lunch to rehydrate doesn’t work. In another study, Seifert tested participants after three hours of skiing and lunch. He discovered that people who didn’t drink while skiing became so dehydrated that they couldn’t even replenish themselves with water and food during a 90-minute lunch. They still ran at a deficit of about a pint of fluid when they hit the slopes in the afternoon. But those who drank during skiing lost only six ounces of fluid, enough to recover during lunch. 

So how much should you drink while skiing? Seifert recommends 12-16 ounces of fluid, either water or sports drinks, per hour. 

“If you can stay on 12 ounces per hour, you’re good. A quart during a morning of skiing is minimal,” Seifert said. “Throw a reservoir in a backpack and take sips every time you ride up a chairlift.”

Hydration Story

Seifert’s study reveals that skiers tend to drink less than they should. Image Courtesy of John Seifert. 

For more information on dehydration while skiing, check here. You can even take a survey to assess your hydration habits.