On a bluebird Saturday in Southwest Colorado, Durango Nordic Ski Club joined forces with the Fort Lewis College exercise science department to add a secret weapon to their training tools: lactate threshold testing.

The testing session was led by Rotem Ishay, director and exercise specialist at the Durango Performance Center and Fort Lewis College’s exercise science lab coordinator; Dr. Melissa Knight-Maloney, chair and professor of exercise science at Fort Lewis; and Melissa Thompson, assistant professor of exercise science at Fort Lewis.

Tad Elliott, head coach and program director of Durango Nordic Ski Club, assisted the session and data collection. A total of 10 athletes participated.

Athletes began the testing by completing a series of functional balance and strength testing exercises before it was time to strap on skis and hit the snow. Each participant then skied five laps of an approximately eight-minute loop, steadily increasing their pace with every lap. The first lap began easy; the last lap was an all-out effort.

“In between each interval, we took their heart rate and their time,” said Elliott. “Then we pricked their earlobe to take a blood sample that would measure the amount of lactate in the blood.”

Lactate, a byproduct of anaerobic metabolism in the body, provides a measure of how hard athletes are going. Lactate threshold is the highest intensity an athlete can keep at a given pace for an extended period of time. Elliott said lactate threshold testing helps athletes identify their training zones and, therefore, train more effectively.

“The fear with children and young adults, especially at high altitude, is that they train too hard too often, and so they’re tired all the time,” said Elliott. “When we’re training easy, the goal is to train easy enough to easily recover from it and build base. As athletes get older, we want to make sure that they understand what easy training is and what it feels like. The lactate threshold test tells you where your easy training zones are so that you’re not constantly building lactic acid.”

According to Elliott, understanding training zones can be especially important for multi-sport athletes, of which Durango has an abundance.

“Being in Durango, a lot of our skiers are also cyclists and use skiing as a way to train for biking,” he said. “When training at nearly 9,000 feet, it’s pretty easy to train too hard, which might not be as beneficial for cyclists when it comes time for them to race in the summer. Determining lactate threshold on snow helps show those athletes the pace they should be going based on their heart rates. We want to keep them in their appropriate zone on skis so they can be better on the bike in the summer.”

Athletes can keep track of their training zones by wearing a heart rate monitor when they exercise, which displays their data on a watch or phone. If athletes don’t have a heart rate monitor, they can use what is called a rating of perceived exertion (RPE) to develop a better feel for their training zones.

Perceived exertion is how hard you feel like your body is working and is based on the physical sensations a person experiences during physical activity, such as increased heart rate, increased respiration, increased sweating and muscle fatigue. While RPE is a more subjective measure, when coupled with date on lactate levels and heart rate, it can be a pretty good estimate of actual effort.

Using RPE can be especially effective for younger skiers, who may not have heart rate monitors and are still developing an awareness for their bodies and effort levels.

Elliott plans to use the data from the testing session to work with Ishay and the Fort Lewis exercise science department to create more effective training plans.

“They’re the experts,” said Elliott. “It’s amazing to have a local resource that can help me adjust training based on what scientists and doctors have to say. They’re helping me understand how to better train skiers, as well as train cyclists as they ski.”