When Ruth Croft was in her final build for this year’s UTMB, she found an unlikely training partner: a ski lift.
Croft won the highly competitive UTMB in 2025, adding to a resume that already included wins at some of the sport’s biggest races, such as CCC and Western States. A year later, she returns to Chamonix as the defending champion and, unsurprisingly, one of the favorites to win again. The challenge for coach Scott Johnston was figuring out where an athlete who had just won the biggest race in the sport could still get better.
One answer. The downhill.
When working with an athlete preparing for a race, Johnston starts with the demands of the event and looks at what is most likely to limit that athlete from performing at their best. Coming off Croft’s win last year, downhill running was one of the clearest areas he thought she could improve.
“The low-hanging fruit this year for Ruth seemed to be in building that fatigue resistance on the downhill so that she would be strong on both the climbs and descents late in the race,” he explains.
That has meant more downhill-specific work, including dedicated sessions where Croft repeatedly takes a lift up and runs 1,000 vertical meters back down at a hard pace.
This has become the biggest change in Croft’s training heading into this year’s UTMB. Along with the downhill-specific work, Johnston has focused on increasing Croft’s overall strength.
“Ruth’s training volume hasn’t increased much this year,” Johnston says. “What has changed is that we’ve done more strength training, more downhill-specific work, and more uphill weighted work.”
The long way down
Croft already gets plenty of descending in her normal training, including downhill tempo efforts during some long runs. The lift-assisted sessions let Johnston isolate that work and add a large amount of fast descending to Croft’s training without adding a big climb beforehand.
“We don’t progress the downhill work in our normal fashion like we do the uphill work,” Johnston says. “We hold the workload steady on these downhill sessions and let her gradually adapt to that workload.”
Fast downhill running places a large eccentric load on the muscles, particularly the quads, as they absorb force with every step. Over the course of UTMB, that adds up to thousands of meters of descending. Johnston wants Croft to be able to maintain more of her running speed after that fatigue has accumulated.
That fits into how he thinks about ultra training more broadly.
“The goal and central principles of this type of training are to improve the fatigue resistance in the main propelling muscles,” he says.
Johnston points to speed at the second lactate threshold as one of the strongest predictors of endurance performance, with speed at the first, or aerobic, threshold closely tied to it. But maintaining that speed for long efforts depends on what is happening locally in the working muscles.
“The single biggest limiter to the speed at the second threshold is local muscular fatigue,” Johnston says. “The athlete slows down because their legs get tired. If we can improve the fatigue resistance of the main propelling muscles, we can improve the speed the athlete can sustain.”
Strength for the long haul
Croft has also increased strength work this year, which Johnston uses as a base before layering in additional specific muscular-endurance training as UTMB gets closer.
Weighted uphill pack carries remain a regular part of the program, with Ruth increasing her workload during this year’s training. During the final UTMB block, Johnston lists weighted uphill threshold intervals, weighted uphill/downhill sessions, and the lift-assisted descending among Croft’s key workouts.
Croft ran NCAA Division I track and cross country before moving into trail racing and has shown plenty of range as an ultrarunner. Last year, she became the first woman to win all three UTMB World Series Finals: OCC, CCC, and UTMB.
“Ruth is an exceptional athlete with very good speed,” Johnston says. “So for a race like UTMB we’ve not needed to focus much on improving that quality and can instead focus on developing more sustainable speed.”
Johnston trains second-threshold speed with elite athletes and carefully controls intensity using blood lactate. For Croft and fellow 2025 UTMB winner Tom Evans, he generally targets around 2.5 to 3.5 mmol/L.
“The goal here, as it should be for any endurance athlete, is to run, cycle, ski, or climb as fast as possible, as aerobically as possible,” says Johnston.
Keeping those sessions controlled also lets Croft carry more total quality work alongside the strength, vertical, and muscular-endurance training that fills the rest of the week.
What a peak week looks like
One of Croft’s biggest weeks in late July before her 2025 UTMB win gives a good look at how Johnston puts the pieces together. Spoiler alert: it’s a lot of running. During this week, she ran 121 miles in 23 hours and 34 minutes with 28,183 feet of climbing.
Monday included a short tempo run into a harder effort at a 20% grade, while Tuesday was split into two easy runs, with 15 miles total for the day. On Wednesday she tackled a three-hour long run, followed by an easy one-hour run in the evening.
Thursday was one of the bigger muscular-endurance days, with tough weighted hill reps, including 3×20 minutes on a steep climb carrying 10 kilograms and using poles. That was followed by an hour-long run and strength work in the gym. Ruth’s Friday structure was similar to Wednesday, with three hours in the morning, followed by an easy one-hour run later in the day.
On Saturday, Johnston had her complete a two-hour trail run, including 30 minutes at roughly 50K race effort on hilly terrain. After what was already a tough week, Sunday was a downhill-specific day, with a three-hour session where Ruth used a ski lift to accumulate roughly 1,000 meters of descending per descent, followed by an easy hour later in the day.
Overall, Johnston hasn’t pushed Croft’s total volume much higher in 2026. The progression has really come through more strength, weighted climbing, and downhill-specific work.
“This is my fourth year of working with Ruth, and we have gradually built her work capacity to the point now where she’s handling significantly more hard training than even last year,” Johnston says. “It takes time to build this sort of capacity. It can’t be rushed.”
Building on a winning formula
Croft’s 2025 win also gives Johnston a useful baseline for this year’s build.
“Since the build to UTMB last year for both Tom and Ruth was so successful, I didn’t see any need to change much,” he says. “Having the dashboard and Performance Management Chart in TrainingPeaks is hugely helpful in this process because it allows me to compare the training loads and her fatigue response to last year.”
With four years of Croft’s training history, Johnston can compare similar workouts and periods of training, along with the bigger picture of how her current UTMB build is tracking against previous successful builds.
Croft and Johnston are also in contact every day. She doesn’t follow traditional scheduled recovery weeks during the build. If her feedback and recent training suggest she needs two or three lighter days, they take them.
The changes for 2026 are fairly specific, with the biggest focus on fatigue resistance on the downhills. After winning UTMB last year, Johnston wants Croft’s legs to be even better prepared for the long descents that come late in the race, when that strength is hardest to hold on to. Her results this year show that she’s in shape to knock another one out of the park, with wins at the Tarawera 100k and the MaXi-Race Annecy 58k, along with a second place finish at the Ultra-Trail Australia 50k.
With UTMB looming, Croft returns stronger, better prepared for the descents, and with another year of work behind her. In a race that keeps getting deeper and faster, she’s ready to aim for the top step of the podium again.
