Final week, Tom Evans and Ruth Croft received the 2025 Utmba in commanding vogue and below traditionally powerful situations. Evans, a British runner who has as soon as podiumed and twice DNFed the race, stormed to victory in 19:18:58. New Zealand’s Croft, who completed second on the occasion final yr, seized management within the race’s remaining third and completed first in 22:56:23.
Each athletes are coached by Scott Johnston of Evoke Endurance, co-author of the now-iconic e-book, “Coaching for the Uphill Athlete.” Johnston’s roots are in alpinism and mountain sports activities like ski mountaineering, which makes his success at teaching athletes for considered one of path working’s premier long-course occasions particularly notable. Central to his teaching is a particular emphasis on fatigue resistance, often known as muscular endurance. Johnston believes fatigue resistance is the one greatest determinant of ultra-distance efficiency, greater than VO2max or lactate threshold.
“The guts doesn’t get drained in these races,” stated Johnston. “What I’ve seen is that athletes are restricted by that fatigue issue out on the muscle.”
Coaching muscular endurance as a substitute of VO2max or lactate threshold is a considerably novel method that appears to be paying dividends for athletes who embrace it. On this article, we discover what Johnston means by fatigue resistance and muscular endurance, and the way he trains his athletes to enhance their skill to keep up their energy and due to this fact their tempo late in an extremely when everybody else slows down.
Tom Evans, 2025 UTMB champion. Picture: iRunFar/Bryon Powell
Fatigue Resistance and Muscular Endurance
Muscular endurance (ME) is your muscle tissues’ skill to maintain repeated contractions or effort over time. Consider it as how lengthy your legs can hold climbing, descending, or pushing on the flats earlier than they offer out. Fatigue resistance is expounded however barely completely different and is outlined as the flexibility to delay the purpose of muscular breakdown. It’s not simply how lengthy the muscle can hold working, however how nicely it could possibly resist the gradual decline in efficiency that comes with hours of stress.
Put merely, muscular endurance is the capability to maintain working; fatigue resistance is the flexibility to maintain that capability from deteriorating. In ultras, significantly vertiginous mountain races like UTMB, the 2 go hand in hand; athletes with robust ME who may also resist fatigue are those nonetheless shifting nicely when opponents begin to crumble.
Ruth Croft climbing the Grand Col Ferret at daybreak throughout the 2025 UTMB. Picture: iRunFar/Eszter Horanyi
That is echoed in a latest opinion paper in “Sports activities Drugs” by researchers Nicholas Tiller and Guillaume Millet. In it, they mixed observational information with earlier analysis to pinpoint muscle injury as the primary impediment to ultramarathon efficiency. One information level within the paper is a survey of 824 ultrarunners, the place 66% pointed to muscle breakdown as their major obstacle.
Prepare Muscular Endurance
Johnston’s background in alpinism informs his method to extremely coaching. He prefers to prioritize muscular endurance work earlier than addressing VO2max or different power programs in coaching.
Johnston observed that lots of his athletes failed to keep up sufficiently excessive coronary heart charge of their higher-end interval work, indicating that their legs merely couldn’t sustain with their already well-developed cardio engines. To repair that, Johnston makes use of event-specific exercises like steep uphill mountain climbing, downhill repeats, weighted vests, and tire-drags to overload athletes’ legs. The aim, based on Johnston, is to emphasize propelling muscle tissues domestically with out inflicting world systemic fatigue related to high-intensity coaching.
Johnston skilled Evans each for his latest win at UTMB and his breakthrough win on the 2023 Western States 100. Whereas his collaboration with Croft is more moderen, Johnston says their give attention to ME was important to their success. Johnston believes that by extra deliberately specializing in ME through overloading the legs in coaching, and never the cardio system, athletes can nonetheless entry a better proportion of their VO2max late in races. In accordance with Johnston, Croft hit her highest coronary heart charge simply 5 kilometers from the UTMB end line, which Johnston factors to as proof of her skill to maintain a better output when not restricted by her muscular endurance.
Coaching muscular endurance allowed Croft to set her highest coronary heart charge of the occasion solely 5 kilometers from the end. Picture: iRunFar/Eszter Horanyi
“For most individuals in these lengthy races, what I’ve labored on is making it so that they don’t see that decline,” stated Johnston. “They will nonetheless entry a comparatively excessive proportion of the VO2max late within the race, whereas if their legs develop into fatigued, then it doesn’t matter anymore in case you’ve received a excessive VO2max of 90 as a result of you may’t even get near it when the muscle tissues are so drained.”
Johnston’s thought is, in case your legs can’t generate power late in a race, your coronary heart’s oxygen-delivery capability is moot. To bridge that hole, Johnston’s coaching, rooted in alpinism and ski mountaineering, seeks to focus on the legs particularly.
Coaching the Legs
In coaching for giant, mountainous races like UTMB, Johnston has athletes hike on steep grades, slopes of 10% to 30%, both with water — which has the advantage of having the ability to be dumped out on the prime of the hill in order that athletes aren’t descending with pointless weight — or a weighted vest. He has his newbie athletes carry about 5% of their physique weight, and elites carry 12% to fifteen%. For terrain-limited athletes, Johnston has them do tire-drags or stair machine classes to focus on the legs, making certain the burn of their legs is the limiter, not cardio capability. He additionally contains downhill repeats and tempo descents to construct eccentric energy.
For elites like Evans and Croft, Johnston introduces this coaching methodology early within the season and carries it by way of the yr, although he recommends that most individuals add it into their coaching the ultimate 10 to 16 weeks earlier than an extremely. He pairs ME-focused coaching with base coaching and energy work, and sees it as a approach of coaching muscular sturdiness whereas preserving athletes’ capability for high-quality classes.
“We by no means do any VO₂max coaching,” stated Johnston. “I’m making an attempt to get the identical muscular impact that you simply’d get from VO₂max intervals, however with out the worldwide fatigue price. You don’t elevate cortisol, you don’t elevate lactate, and restoration is far sooner.”
Tom Evans main the 2025 UTMB late within the race. Picture: iRunFar/Eszter Horanyi
To gauge the effectiveness of his coaching and observe athletes’ progress, Johnston depends on a number of metrics, together with continual coaching load (CTL). Calculated in TrainingPeaks, a digital coaching platform that Johnston makes use of along with his teaching shoppers, CTL gives a six-week exponential shifting common of an athlete’s coaching stress. That metric, amongst others like ramp charge and general evaluation of their coaching stress, helps Johnston tailor the coaching to every particular athlete.
Croft appears to have benefited from Johnston’s method and says, “I’d need to say that Scott’s coaching method is kind of unconventional. His classes focus closely on constructing muscular endurance and tailoring the work to the precise calls for of the course. However past the coaching itself — and one thing usually neglected in teaching, is the connection and suggestions between coach and athlete. Outdoors of my companion, Scott has been the particular person I’ve had probably the most contact with every day. That degree of constant interplay and assist is, for my part, what separates a great coach from a very nice one. This system issues, however the relationship makes all of the distinction.”
“Understanding the work capability and restoration charge of the athlete is necessary for locating the restrict of what they’ll safely deal with,” stated Johnston. “With an elite, in some over-reaching blocks, we will see CTL will increase of 10 to fifteen per week. Each athlete is completely different and must be handled individually.” For a lower-tech approach of assessing progress, Johnston recommends athletes construct a cairn, or go away a stack of rocks on the hillside the place they do their intervals, encouraging them to repeat exercises on the identical hill, and see in the event that they transfer the cairn uphill over time.
Is Muscular Endurance the New Secret?
Whereas ME-specific coaching is core to Johnston’s philosophy, some query its centrality and relevance to all athletes. Whereas consensus factors to ME being necessary, how precisely to go about it’s up for a bigger debate. Some proponents argue that elevated quantity has the twin good thing about each constructing cardio capability and rising muscular resilience and endurance, and that focusing an excessive amount of on ME to the detriment of cardio growth could be sacrificing greater advantages for a marginal acquire.
Cliff PittmanTeaching Improvement Director for CTS and an expert ultrarunning coach, says ME is one piece of a bigger puzzle.
“ME is completely one of the crucial necessary determinants of efficiency in ultrarunning,” stated Pittman. “But it surely’s not an adaptation that must be remoted in case your coaching is already race-specific. For my part, ME is addressed implicitly within the coaching of any athlete logging constant quantity over acceptable terrain, particularly whereas carrying their required race-day gear. We simply name it endurance coaching as a result of it’s all-encompassing.”
That assertion is echoed by Tiller and Millet’s paper, which factors to coaching quantity alongside energy coaching and fueling, reasonably than particularly concentrating on and overloading the muscle tissues by way of weighted coaching and tire-drags, as being contributors to success. Different research have additionally strongly pointed towards coaching quantity as a significant predictive consider ultramarathon efficiency.
Ruth Croft, 2025 UTMB champion. Picture: iRunFar/Bryon Powell
Strategies of overload, like utilizing a weighted vest whereas working or mountain climbing uphill, are additionally debated within the literature. The aim is to extend the load being carried by muscle tissues, however proof means that the added resistance meaningfully adjustments the entire working or mountain climbing motion. Not solely can that make coaching much less particular — a 2023 examine discovered that carrying weights that exceeded 10% of skilled path runners’ physique weight altered their biomechanics and negatively impacted their efficiency at submaximal velocity — however it could possibly additionally enhance danger for damage in some cases.
All of this stated, UTMB is a singular check case in that it includes loads of mountain climbing, even for an ultramarathon. Evans’ information, Johnston stated that the athlete spent about half the race mountain climbing.
“Working and strolling are very completely different actions,” stated Johnston. “It’s like a special sport, and also you really need to coach them.”
Pittman agrees that particular occasions advantage particular interventions, like concentrating on stronger powerhiking for UTMB. However he worries that some nuance may get misplaced within the weeds. Pittman factors out that athletes who’re too centered on synthetic ME interventions may sacrifice cardio growth, the true cornerstone of extremely coaching.
Last Ideas
On the elite degree, marginal good points in muscular endurance, like what lets you hit one’s prime coronary heart charge late within the UTMB like Croft did, could make or break a efficiency. Ultramarathon success is multifactorial, and whereas two standout outcomes don’t represent proof, the highlight on Johnston’s strategies highlights an space of coaching that will deserve extra consideration. It’s not a silver bullet — no single component of coaching is — nevertheless it gives a helpful lens for understanding success.
What is obvious is that as the game grows extra aggressive, coaches and athletes might want to go away no physiological stone unturned to remain on the prime.
Tom Evans was capable of outrun and outlast everybody else on the 2025 UTMB. Picture: iRunFar/Eszter Horanyi
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