The American Birkebiener

The American Birkebeiner website notes that more than 250,000 individuals have completed its ski events since the race began in 1973.

First held in 1973, the race was cancelled in 2000 and 2017 due to poor snow conditions. In 51 years, thousands of skiers have received a coveted finisher’s medal.

The Birchleggings Club celebrates the accomplishments of skiers who have completed 20 or more 20+ Birkie or Kortelopet, or combined finishes.

Birchlegging members wear a special purple bib. After the 2025 race, the Birchleggings Club had 322 male and 61 female members.

In 2013, race organizers split the event into two races, representing two disciplines: skate (51 km) and classic (53 km) disciplines.

Fans of most competitive events are always interested in the numbers. Fastest time. Average time. Time by discipline. Time by gender. Average time over a period of years.

Through the efforts of James Coors, a retired professor of agronomy at the University of Wisconsin-Madison, Silent Sports is presenting a collection of detailed graphs documenting the American Birkebeiner, by the numbers.

Coors has skied the American Birkebeiner an amazing 36 times. Now 75, he’d like to ski the Birkie again, but he’s nearing the point where every new year is more an act of serendipity than a planned event.

Coors has always enjoyed working with large datasets, stemming from his work at UW-Madison as a research geneticist/biostatistician/plant breeder. Most of his work involved field-based research evaluating extensive plant germplasm collections over multiple years and varied environments. Creating summaries from large datasets that capture performance potential in meaningful ways is an enjoyable pursuit.

Only now, instead of plants, Coors wants to focus on summarizing the performance of thousands of skiers over decades of the Birkiebeiner. The challenge is just as great given the tremendous variation in weather conditions, alterations in course/race management, and demographic shifts.

The website XCSkiStats.info (aka Birkie Stats) reviews results from 1999 through 2025 of the marathon-length (~50- 55k) American Birkebeiner cross country ski race, which is commonly referred to as the “Birkie.” A large dataset containing 108,000+ individual results was assembled to address several interesting questions. The primary focus is on how age affects performance. Cross-country skiing may be unique among endurance sports in that excellent performance can be extended well into the sixth decade and beyond. But this varies depending on skill level, gender, and technique.

Other interesting issues include how classic and freestyle techniques compare historically and whether the relative performance of male and female skiers has changed over the years.

Coors is the founding president of the Foundation for the Endowment of the American Birkebeiner, and designed XCSkiStats.info to highlight that organization. Coors supports the Birchleggings Club, which is also featured prominently in these charts.

This project has benefited greatly from the help of Dave Armstrong, Liam Johnston, and John Oman.