The March cold-snap debrief.

Thirteen members of our panel skied the American Birkebeiner on the last Saturday of February. The course conditions were the coldest in the race's recent history — air temperature at the gun in Cable was −18°F, falling to −22°F at the front of the field; wind chill bottomed out at −38°F; the start was held until 09:30 to give the air a chance to warm into the −12°F band, which it eventually did. None of our panel withdrew. Twelve finished. One fractured a left distal radius on a downhill at the OO crossing and skied the remaining 24 km on it; he and his wrist are now doing well. Nobody, to our knowledge, took home a frostbite injury.

The number we wanted at the post-race clinic was not "thirteen finishers." It was the cold-injury count. The cold-injury count was zero. That is the result we were trying to engineer in the eight weeks before the race, and we were not entirely sure we had earned it. What follows is a debrief of what we counselled, what worked, and what we will do differently for the 2027 cycle.

The pre-race visits

Beginning in early January, every Birkie-cycle member of the panel came in for a 45-minute pre-race visit. The visits ran on a structured template — based loosely on the Wilderness Medical Society's 2019 cold-injury guidelines^[1], the AMSSM position on cold-weather competition, and the CDC NIOSH cold-stress reference — and the agenda was always the same: layering, exposed-skin management, hydration in cold, fueling at low temperatures, peripheral perfusion (especially fingers and toes — the failure modes there are real and not always reversible), and a brief conversation about when to not race.

The "when to not race" conversation is the one I was the most prepared to lose. The race is a sunk cost — entry fees, hotel, six months of training, the social commitment of a wave of friends — and the cognitive incentive to start is enormous. The data we have on cold-related event injuries is limited; the narrative experience of cold-related disasters at endurance events is vivid. We pushed, in every visit, the position that finishing a race is not a clinical achievement and not finishing one is not a clinical failure. Whether the position took, in any given member, depended on the member.

What worked

The single intervention I am most confident about, in retrospect, is the wax-handed cheek-and-nose check. Members were instructed to apply petroleum jelly or a cold-weather face balm to nose, cheeks, and any exposed skin in the staging area, and to have a buddy do a visual check at the start line. Several members reported buddy-checks catching early frostnip during the race itself; one member's wave-mate flagged them at the OO aid station, and they spent ten minutes warming the face under a buff before continuing. The intervention is cheap and the negative cost is low. Recommend.

The hand-warmer-in-glove protocol — disposable hand warmers in lobster mitts, replaced at OO and at Hwy 77 — produced no peripheral problems in our skiers. We had counselled against bare hands during course-condition checks, and we had counselled against thin race-style gloves at the start. Some members reported the lobster mitts being cumbersome on poling; nobody reported losing finger function.

The pre-race fluid loading conversation also went better than I expected. The hard part of cold-weather endurance hydration is that the body's thirst mechanism is suppressed at low temperatures^[2], and dehydration progresses without obvious cues. Pre-race fluid loading — 16 oz of warm electrolyte drink in the staging area, plus a hot bottle in the warming bag — meant that nearly every member started the race already on the right side of euvolemia, and we had only one mild post-race orthostatic hypotension presentation in the clinic.

What didn't

The race-day fueling was less orderly than we had hoped. Several members reported gel packets freezing solid in chest pockets despite the recommendation to keep gels close to the body. One member resorted to chewing a chocolate-and-almond bar that had become rock-hard; another lost a tooth filling on it. The lesson, for 2027: liquid carbohydrate sources (fluid bottles in the chest, kept warm by body heat) are more reliable than gels in cold below −15°F. We will counsel that explicitly next cycle.

The "when to not race" conversation worked better with first-time Birkie skiers than with seasoned veterans. The veterans had already raced colder days; their personal narrative of "I've handled this" carried significant weight against the abstract risk argument. I do not have a fix for this. I do think the conversation needs to happen earlier in the cycle — November rather than January — so the cognitive sunk cost is smaller.

The fracture

The distal-radius fracture happened in the way distal-radius fractures usually happen on a Birkie-style course: a fall on a frozen downhill at OO, an outstretched hand to break the fall, an audible crack the skier dismissed because the skier wanted to keep moving. He skied to the finish — twenty-four kilometers on a closed extra-articular distal-radius fracture — and presented to the medical tent at Telemark. He was casted in Hayward and follow-up imaged at Aspirus St. Luke's three days later; he is doing well in a removable cast at three weeks.

Skiing on the fracture did not do him a kindness. It did not, in his case, change the management — the fracture remained extra-articular and well-aligned — but the principle is the principle, and we should not learn the principle from the cases where the gamble paid off. The next time a member describes a hard fall on a downhill with an audible crack, I want them to stop. That is the conversation I would like to have already had in pre-race visits, more directly than I did.

Closing the loop

Thirteen members. Twelve finishes, one fracture, no cold injuries, one tooth, two minor post-race orthostatic episodes, three rounds of "I needed to take a fifteen-minute warming break and I felt bad about it but I shouldn't have." We will run the same pre-race protocol for 2027 with the November timing change and the gels-to-liquids change. We will also add a 30-minute group session in early February for first-time Birkie skiers in the panel, taught by Vass with one returning veteran member, focused entirely on the on-course decision-making in the cold. We have agreement from a 2026 finisher to teach with us.

The chronograph metaphor for this debrief: the race is the lap; the medical work is the pre-race timing analysis. The lap times we recorded — the fluid load, the wax check, the layering — are the splits we will improve next time.

— OV