Heather Jackson: from elite triathlete to ultra running champion

HOKA athlete Heather Jackson won the Canyons 50K in April. Photo provided by HOKA

By Henry Howard

Heather Jackson, fresh off a course record at the Unbound gravel cycling championship, returns to Western States this month after her top 10 finish a year ago.

In 2024, she finished as the seventh woman at Western in 17:16:43. She is the top returning American woman runner and among six runners who finished in the top 10 last year. Jackson is somewhat new to trail and ultra running after a successful competitive career in triathlons.  

As a young girl, even a toddler, Jackson focused on team sports growing up in New Hampshire.

“We were always outside skating on the frozen pond because early on my focus was ice hockey,” she recalls. “But even prior to that, I was playing everything, soccer, tennis, basketball, softball, lacrosse. My mom was a phys ed teacher, so she kind of had all four of us, four kids in everything with her after school.”

Jackson, a HOKA sponsored athlete, played ice hockey through college and fell just short of making Team USA in the 2006 Olympics. Soon after her college graduation, she jumped into her first triathlon, a sprint, called Race to the Face.

“I was just absolutely addicted to the thought that I did it,” she says, comparing the individual pursuit versus her experience playing on teams. “And the second it finished, I was like, oh my gosh, I could have gone so much faster if I had done this or that. I hadn't actually even really trained for it. It was more just a fun thing. I had literally just finished playing ice hockey, so this was a personal test.”

Jackson turned pro in 2009 and raced triathlons professionally until the Kona World Championship in 2022. Among her most notable achievements were the all-time fastest Ironman by an American, thanks to her 8:39:18 at Arizona in 2018. She also has four top five finishes at Kona in 2015, 2016, 2017 and 2019.

Making the transition

Jackson is not the first triathlete to venture into trail running but arguably the most successful among today’s top athletes. What does she recommend for other triathletes and cyclists who are thinking about transitioning to trail and ultra races?

“My biggest advice is just to give it a try,” she says. “I wish I had started doing it way earlier. I think it's so fun. It's running and you're testing yourself and you're pushing yourself, but you're in some of the most beautiful terrain. There's so many different types of courses. There's so many different things. Versus triathlon which was just very much the same. You're on a paved road. The marathon or the half marathon was almost always the same. Maybe a couple of rolling hills, but not like trail running hills or hiking mountains.”

She also says that experienced athletes will be able to adapt quickly.

“I just would encourage everyone to just try it,” she says. “And then you’ll figure out your weaknesses pretty quickly. For instance, for me, not having run off road a lot, it's been the technical side of things, learning where to place your foot, how to not roll my ankle every run.”

‘It’s a special race’

Jackson’s first trail race was the Javelina Jundred, just two weeks after her final race at Kona in 2022. After crossing the finish line in fifth place, her thoughts mirrored that first triathlon way back in New Hampshire: “I could get better at this. I could change what I did here. I could train better.”

Admitting she hadn't prepped for Javelina specifically, she relied on her fitness as an endurance athlete.

“I had only ever run a marathon, and I just went there and started running,” she remembers. “I led the race until about mile 80. And then the wheels just came off so hard. But literally, I couldn't walk for a week, but I was hooked. I thought, ‘If I did this differently, then I could be ready for these races.’ So it was exactly the same.”

And she was ready for the following year’s Javelina, where she took the win, lowering her time from 15:42:18 to 14:24:47. The victory assured her a spot in last year’s Western States.

“It's a special race,” she says. “I knew about it coming from triathlon and maybe a couple others like UTMB. But this was the race I followed even prior to getting into the sport. It's what I knew about trail running. To be able to be a part of it and be one of the runners who gets to toe the start line, it's so special. I don't take that for granted and I feel grateful to be a part of it.”

Just a few weeks ago, Jackson shattered the women’s course record at the Unbound XL, a 359-mile gravel bike race, finishing eighth overall in 20:57:57. Last year before Western States, she took fifth at the 203-mile version of Unbound in 10:26:03.

“It took probably three or four days to really recover,” she says of the 2025 Unbound. “My body honestly felt better than if I had raced the 200-miler because it's a different type of effort. It's a steady, consistent effort. It was more getting over the fact that I didn't sleep that night. It was a 21-hour event. So just getting over that lack of sleeping Saturday night.”

Jackson puts it into perspective.

“For me, I think honestly it’s a good race to have done, because in my mind, that was a 21-hour race,” she says. ”Now I'm hoping to go under 17 hours, 16 hours at Western States. It's going to hopefully feel short. When I break it down in my head of the time sections … five hours to Robinson, then another four … it makes it seem not as daunting.”

Impact on Western States

She approached Unbound as a last training effort for Western States, practicing nutrition, for example.

“A lot of people are out there running 40-, 50-mile runs, and that's great too for their prep if that's what's called for,” she says. “But for me, if I was doing that, I would be so tired and trashed and just muscularly fatigued. I got this effort in and the fueling practice, the cooling practice, all the things without necessarily the pounding on the legs that a 21-hour day would've brought. So I'm seeing it as a good final, long day out and have had a good two week or so block since then running.”

The 2025 Western States chatter has largely focused on the incredibly competitive men’s field. The women’s field also has elite runners, even while lacking previous top athletes like course record holder Courtney Dauwalter and last year’s winner, Katie Schide.

One thing is certain, however: a new women’s champion will be crowned.

“Courtney and Katie aren't there, so maybe people are kind of dismissing it,” Jackson says. “But obviously I think all female runners would want them there because everyone wants to see how they do against the absolute best field out there. It's wide open. And that's exciting. There are 20 different women who could break the tape this year. That's why this year is going to be super exciting for the women's field.”

Hooked on HOKA

On race day, Jackson will be wearing a yet-to-be released model that she has been training in. She’s been with HOKA for over a decade.

“I cannot say enough about my partnership with HOKA,” she says. “They supported literally the last eight, nine years of my triathlon career. And I didn't necessarily know what that would look like as I phased out of triathlon.”

But it was HOKA’s Mike McManus at Kona who helped get Jackson into her first Javelina when she expressed interest in trying the Golden Ticket race.

“I love sharing that story because HOKA was the first one to support me wanting to make this transition,” she says. “He was at Javelina two weeks later and was in my crew tent, there for me. HOKA has been there from that whole triathlon career into now. It’s a dream come true to continue to be able to represent them and have their support in the trail running world.”

While Jackson’s trail running career is only beginning, there will come a day when it concludes. What would success look like down the road?

“Success is not about the results or the races even,” she reasons. “It's about looking back, it's the relationships that I made. Thinking of your question in relation to triathlon, the success to me in that sport was all the friends I made, all of just the memories I had in those 15 years of my life that I look back on. The races themselves are probably 1% of my memories. And so the same thing with the trail running. It's even in just the last three years, it's been about the friends we've made and the memories made in the training, the races, the travel, things like that. I get to race and it's a privilege. But for me, success is just having enjoyed this journey every single step of the way and making the most of every single day.”