The Trail Running Briefing

In Episode 36 of The Trail Running Briefing , I take you through the ARC100 by UTMB from the perspective of someone who has raced it twice, in 2025 and 2026. This episode is designed as a practical course guide for runners preparing for the race. I break down the key sections of the route, including the wet and boggy terrain around Lizard Point and Mullion, the runnable stretches towards Penzance,...

Cross-training can be a valuable tool for ultrarunners, but it should always serve a clear purpose. In this episode of The Trail Running Briefing , I explore why specificity still matters, especially for mountain ultrarunners. A long ultra is not simply one discipline: it involves running uphill, running flats, running downhill and, very importantly, power-hiking steep climbs. We look at why uphil...

Mental toughness in ultrarunning is often misunderstood. It isn’t about ignoring pain, refusing to walk, or proving how much suffering you can tolerate. Current research suggests the more useful skill is how you respond when things become difficult. In this episode, I look at what the evidence tells us about mental toughness, pain coping, resilience and self-efficacy in ultra-endurance running and...

Episode 33 explores running injuries through a simple risk-management lens: Risk = Probability × Impact . The central idea is that ageing does not automatically make runners fragile or guarantee a higher injury risk, but the consequences of a significant injury can become more costly because rebuilding lost strength, fitness, tendon capacity and race-specific durability may take longer and disrupt...

In this episode of The Trail Running Briefing, we explore cardiac drift: why heart rate can gradually rise during long runs even when pace or effort appears unchanged. We explain the relationship between heart rate and stroke volume, why heat, dehydration and prolonged exercise increase cardiovascular strain, and how this matters specifically for ultrarunners. We also look at aerobic decoupling an...

Peak form is not simply about being as fit as possible. It is the point where high fitness meets low fatigue, allowing an athlete to fully express the adaptations built over weeks and months of training. Hard training develops aerobic fitness, strength, durability, climbing and descending ability, but it also creates fatigue. This means runners can sometimes be getting fitter while temporarily fee...

In Episode 30 of The Trail Running Briefing, we explore why ultrarunners sometimes stop improving even when they are training consistently and working harder. A plateau doesn’t always mean you need more mileage or more intensity. It can mean your body has adapted to the same training stimulus, accumulated fatigue is hiding your fitness, recovery or fuelling is insufficient, or your training is no...

Ultra running demands far more than just mileage. Long runs, back-to-backs, strength work, fuelling, recovery, work, family and everyday stress all contribute to the total load an athlete carries. In this episode, I explore burnout in ultrarunning , how it differs from normal fatigue or overtraining, and why it can gradually turn something we love into something that feels like an obligation. We l...

Episode 28 explores how ultra training should evolve with age without lowering ambition. The central idea is the recovery budget : every long run, hard session, strength workout and race creates stress, while sleep, work, nutrition and life commitments affect how quickly that budget is restored. As runners get older, training does not necessarily need to become easier, but it should become less cr...

After a DNF, remember this sequence: Feel it. Separate it. Learn from it. Then move forward. Feel the disappointment without shame. Separate the facts from the story you are telling about yourself. Extract a small number of useful lessons. Then rebuild through ordinary, consistent action. A DNF is painful because the goal mattered. But it is a result, not an identity. It records where one race end...

Durability is the ability to preserve your performance as fatigue accumulates during prolonged exercise. While fitness describes what you can do when fresh, durability determines how much of that fitness remains after many hours of running. In a 100K or 100-mile race, pace can decline because of muscular damage, worsening running economy, reduced force production, poor fuelling and mental fatigue....

In this episode, we cover why carb loading is not about eating a huge bowl of pasta the night before a race, but about arriving at the start line with full fuel stores. For trail and ultra runners, glycogen is the body’s fast-access fuel, and starting underfuelled can make the later stages of a race much harder. The key message is simple: carb loading should be planned, practised, and spread acros...

In this episode, we look at one of the most important skills in ultrarunning: managing the low points. Every runner will face dark moments during an ultra, but a low point is not necessarily the end of the race. It is usually information: you may need fuel, fluids, sodium, cooling, warmer clothing, slower pacing, or simply a mental reset. The key message is: do not make big decisions from a low po...

In this episode, we explain the difference between heat acclimatisation and heat acclimation. Acclimatisation usually refers to adapting naturally to a hot environment, while acclimation is a more controlled process using tools like hot-water immersion, sauna, or structured heat exposure. The key message is that heat adaptation is not just about “getting used to suffering.” It creates real physiol...

In this episode, we explore one of the most important principles for sustainable ultrarunning progress: using the minimum intensity needed to create the right adaptation . The goal of training is not to suffer as much as possible. The goal is to apply the right stimulus, recover from it, and repeat it consistently over time. Whether we are doing intervals, hill work, downhill sessions, strength tr...

Elite trail runners do not descend faster simply because they are braver. They descend faster because they brake less. Downhill running creates a lot of muscle damage because the quadriceps are working eccentrically: they produce force while lengthening to control the body against gravity. Every downhill step is like a small controlled landing. When runners overstride, lean back, tense up, and lan...

Caffeine is one of the most evidence-supported supplements for endurance performance, but ultrarunners need to use it strategically rather than simply taking more. The key message is that caffeine is not fuel. Carbohydrates provide energy for the muscles; caffeine mainly helps with alertness, focus, motivation, and perceived effort. This makes it especially useful in long ultras, where mental fati...

In this episode, we explore why many trail and ultra runners feel that their breathing is still under control, but their legs simply stop working. The main idea is that ultra running is not limited only by cardiovascular fitness. It is also limited by local muscular endurance : the ability of the quads, calves, glutes and stabilising muscles to keep producing force for hours. Climbing, descending...

This episode explains why running performance drops in hot conditions and why it is not simply a loss of fitness or lack of toughness. In the heat, the body has two jobs: keep running and protect itself from overheating. More blood is directed towards the skin for cooling, sweat rate increases, heart rate rises, and the same pace costs more energy. The key message is that on hot days, effort matte...

In this episode of The Trail Running Briefing , we explore why choosing a race with purpose can be a powerful part of ultra-distance performance. Training, pacing, fuelling, strength, and recovery all matter, but when a race becomes difficult, runners also need a strong reason to keep moving. Purpose gives suffering direction. It helps runners stay patient, calm, and committed when fatigue, bad we...

This episode explains why recovery is one of the biggest limiting factors in ultrarunning performance. The key idea is that training does not create fitness by itself, training creates stress, and recovery allows the body to adapt. The episode challenges the common mistake of treating recovery as something you can buy or add at the end, such as massage, compression boots, red light therapy, or oth...

Tapering is not about resting, it’s about absorbing the training you’ve already done . After weeks or months of building fatigue through long runs and hard sessions, your body needs time to recover and convert that work into performance. Without a proper taper, you arrive at the start line carrying fatigue instead of fitness. The goal of tapering is simple: reduce fatigue while maintaining fitness...

Hydration in long trail running is not just about drinking water. It is about replacing enough fluid and sodium to stay functional as conditions, duration, and sweat losses increase. This episode explains why runners can drink plenty and still feel flat, thirsty, heavy, or cramp-prone when sodium intake does not match the demands of the session. It also unpacks the simple idea that water replaces...

HRV, or heart rate variability, is not a score that tells ultrarunners whether they are fit or unfit on a given day. It is a signal of how well the body is handling overall stress. That stress comes not only from training, but also from sleep, work, travel, fuelling, illness, and life outside running. The key idea in the episode is that HRV is most useful when viewed as a trend , not as a single d...

Training fatigue is normal. Overtraining is not. And very often, what runners call “overtraining” is actually a mix of excessive load, poor recovery, and under-fuelling. This episode explains the difference between normal fatigue, non-functional overreaching, true overtraining syndrome, and Relative Energy Deficiency in Sport, or RED-S. The key message is that not all fatigue is the same, and the...