American endurance athlete Tyler Andrews' record-breaking ascent of Mount Everest has ignited a fierce debate within the climbing community. Critics question whether his 9-hour, 55-minute summit push from Base Camp benefited from an earlier route reconnaissance climb that used supplemental oxygen.
The Record-Breaking Ascent
Andrews, a 36-year-old cancer survivor, reached the summit on May 28, the last day of the climbing season, and returned to Base Camp in 16 hours and 32 minutes. This broke a 23-year-old speed record on Everest's South Side, making him the first non-Sherpa climber to hold the South Base Camp speed mark. However, scrutiny soon focused on his aborted attempt on May 24.
Controversy Over Pre-Climb
For two years, Andrews had aimed to break the no-oxygen Everest speed record set by French climber Marc Batard in 1988. On May 23, he left Base Camp without supplemental oxygen but turned back near the Balcony at approximately 8,500 meters due to shifting weather and altitude complications. Critics argue that this climb allowed him to study key sections, plan his speed push, and acclimatize before his successful attempt.
Lukasz Borowski, a Polish alpinist, stated, “People don't understand how much easier route-finding is when your brain actually has oxygen. He memorised the placement of every technical ladder and rope section while completely clear-headed on his first turn. When you go back to run it fast, that mental blueprint is a massive tactical advantage over someone navigating the icefall in a hypoxic haze.”
Pemba Tenzing Sherpa, a veteran high-altitude logistics coordinator with 12 Everest summits, added, “If you breathe bottled O2 at 8,000 meters during a scouting run, you are actively preserving muscle tissue and letting your nervous system recover. Coming back down to Base Camp and running back up a few days later isn't a clean slate. You are riding a wave of oxygen-assisted cellular recovery that a true no-O2 climber never gets.”
Widening Grey Area in Speed Climbing
Spanish mountaineering great Kilian Jornet, who summited Everest twice in a week without supplemental oxygen in 2017, was among the strongest critics. The dispute highlights a growing ambiguity in Himalayan speed climbing. Billi Bierling, managing director of the Himalayan Database, noted, “The lines used to be very clear: you either used gas or you didn't. Now, we are seeing athletes combine multiple strategies—using oxygen on Monday for safety or routing, flying down by helicopter to heal their lungs, and then attempting an unassisted or assisted speed run on Friday. It creates a massive taxonomy problem for historical tracking.”
Andrews Defends His Achievement
Andrews rejected suggestions that the controversy diminishes his feat, arguing that assisted and unsupported climbs should be separate categories. “No, it doesn't take anything away from me. They are different marks, but I can't tell that one is harder than the other from an athletic perspective. I have always been motivated by pushing my own limits as an athlete, and going to the summit in 9h55 (and back in 16h32) is one of the hardest things I've ever done. Climbing without gas is maybe a different kind of hard, but I know that I left everything out there.”
Supporters argue that critics are moving the goalposts. Markus Vance, an ultra-endurance coach, said, “The clock does not lie, and he didn't use a single drop of oxygen during the first legs of that 9-hour, 55-minute push. Unless there is a governing body that outlaws supplemental gas during a previous week's acclimatization, a record is a record.”
