In 2025, the Mammoth 200-miler was established to push the limits of endurance across California's Sierra Nevada region. At the inaugural edition, Rachel Entrekin rose to the occasion, claiming victory in the women’s race and etching her name into the record books as the event’s first course record holder.

The Course: A Brutal Sierra Nevada Loop

The race, known officially as theMAMMOTH, is an adventure through some of the most rugged terrain California has to offer. The 214-mile (344 km) route winds its way around Mammoth Lakes and deep into the Sierra Nevada backcountry.

Key highlights of the course:

• 31,000+ feet of elevation gain with relentless climbs and quad-busting descents.
• High-altitude exposure with much of the course hovering above 7,000 feet.
• Remote and technical trails that require focus and resilience
• Variable mountain weather, from scorching daytime heat to chilly alpine nights.

Rachel put the challenge in perspective: “I actually think that for the distance, 30k of gain isn’t that unreasonable. I just spent a lot of time running terrain that was similar to the race course, and stacking weeks of 100-110 miles with 20-25k of gain.”

This course demands strategic pacing and strong navigation, as sleep deprivation and fatigue compound to complete the race under the 110-hour cutoff. Finishing alone is a triumph; racing it at record pace is extraordinary.

Training for the Mammoth 200

Rachel’s preparation for the event was methodical and relentless. “Generally, I don’t dip below 70 miles per week, with the other three weeks being 85–115 miles or so. I did do one week of over 150 miles on the course. I typically run 5–6 days a week.”

That training gave her the confidence to take on such a massive unknown. “I did feel confident, even though I wasn’t sure what the outcome would be. My fitness felt great and I’ve got a good bit of experience with the multiday racing, plus a stellar crew. These races are mostly about problem solving in the moment, and I felt good about mine and my crew’s abilities out there to figure things out quickly.”

When asked how she prepared for a first-year race, she said: “I went out to scout the course about three weeks before the race to get to know the area. If you’ve not run the course, or don’t have a way to check it out, do your research on the area and try to find trails you can access and practice your race strategies on those!”

What Happened on the Trails of the Mammoth 200

The Mammoth 200 began with a steady, tactical pace. Rachel tucked in alongside Appalachian Trail FKT-holder Tara Dower through the early miles, the two pushing each other across the first 80 miles. “I think her company made those opening sections feel lighter,” Rachel recalled. But when Dower dropped from the race, Rachel settled into her rhythm.

She encountered pivotal choices as the miles wore on. “There were a couple times I probably should’ve tried surging forward, but held back because my usual mindset of outlasting people has usually been successful. Jimmy Elam held on really well to the lead, and as a result, I wasn’t able to pass him.”

Through it all, Rachel remained composed and joyful. “To be honest, I felt good the whole time. I think surrounding yourself with your loved ones, staying on top of your nutrition, and having a good reason to be out there kept my headspace positive.”

Numbers That Tell the Story

Rachel completed the punishing 214-mile loop in 46:50:55, taking women's first place, 2nd overall, and establishing the women’s course record. By the finish, she had built a nine-hour gap over the next woman, Amber Weibel, and was just 90 minutes behind men’s champion Jimmy Elam.

She crossed the line seeming unshaken, even quipping to the crowd: “That was fun … who’s in for one more loop?”

This victory marked Rachel’s 18th consecutive ultra win—a streak that speaks volumes about her consistency, durability, and mental toughness.

A Year of Breakthroughs

Mammoth 200 wasn’t Rachel’s only headline-grabbing performance in 2025. Earlier in the season, she tore through the Cocodona 250, shattering the women’s course record by more than seven hours. Her 2025 race calendar shows a series of high-level performances: wins in races from 100-mile to 250-mile events.

Crossing the line at Mammoth wasn’t just about this race, but part of a bigger story of steady, proven strength across ultra distances.

Rachel put it best when reflecting on her season and looking forward: “We are much more capable than we might think! I’ve had big opportunities to race huge names within the sport this year, and even though it’s been nerve-wracking, each time I’ve toed the lines with the Greats I’ve found an extra gear I didn’t know I had. Never be afraid to stick your nose in it, because you just might walk away surprised!”