Ultra and trail running training: climbs, descents, fuelling and safety

How is trail running different from road running?

On the road every step looks like the last; on a trail none do. The surface keeps changing, your ankles make small corrections on every stride, your heart rate rises while your pace collapses on the climbs, and the descents load your legs in a completely different way. Strong road runners are often surprised on their first trail outings: the same effort means a much slower pace, and the same distance takes far longer.

That is why pace is a much weaker target on trails than on the road. Ten kilometres on a technical course can take as long as a road half marathon. Planning by time and effort rather than distance and pace works far better: a target like "two hours at easy effort" means a similar load whatever the terrain. Tracking effort through perceived exertion (RPE) or heart rate is a more honest guide than the pace on your watch.

In an ultra the gap grows even wider. In a race lasting many hours, what decides the outcome is not your top speed but your ability to move efficiently while tired, a stomach that keeps accepting food, and patience. Ultra preparation is therefore less about getting faster than about getting more durable. Long, steady sessions form the backbone of the plan; hard sessions take up less room but still have a job to do.

How do you train for climbing and descending?

On steep climbs, running is often less efficient than walking. Power hiking is a fast uphill walk with your torso leaning slightly forward, short and purposeful steps and, when needed, hands pressing on your thighs; experienced ultra runners cover much of a long climb this way. Walking is not failure, it is tactics. To work on race day it has to be practised, so build deliberate hiking sections into your long runs.

Descending is the most underrated part of trail running. On every downhill step the muscles at the front of your thigh lengthen while braking the load; this eccentric work causes far more muscle damage than flat running. The soreness you feel walking downstairs a day or two after a long descent is the result. In races it is often the descents, not the climbs, that finish your legs, so descending durability has to be built gradually in training.

Good descending technique protects both your legs and your ankles: short, quick steps, eyes a few metres ahead, arms slightly out for balance, and weight over the middle of the foot rather than the heel. Start with short, controlled downhill sections and lengthen them over the weeks. Give eccentric movements a place in your strength work too: step-ups with a slow, controlled lowering and lunges prepare the muscles that brake on the way down.

How do long runs and back-to-back long runs fit in?

In trail and ultra preparation the long run is the centre of the plan, but it is measured by duration and terrain rather than distance. Most of it is run at easy effort, ideally on ground that resembles the race. The load rises gradually over a few weeks, then a lighter week follows. Doing long runs with the shoes, vest and fuel you will use in the race turns each one into a rehearsal as well.

A tool ultra runners often use is running long or medium-long on two consecutive days, known as back-to-back long runs. On the second day your legs are already tired, so you get a feel for the second half of a race without paying the large recovery cost of one very long run. It needs care: keep both days at easy effort, add them only once a solid base is in place, and keep the days that follow light.

Running well while tired, often called durability, is decisive over ultra distances. Adding a short, controlled section at race effort to the end of a long, steady run is one common way to develop it. The goal is not speed but holding your stride, posture and judgement after hours on the move.

How do you prepare for the mountains if you live in a flat city?

Not everyone has mountains on their doorstep, but there are plenty of ways to mimic the load of climbing. A treadmill incline is a good tool for long, steady ascents, and walking at a steep incline is the easiest way to practise power hiking. If you will race with a vest, train with it. Find the longest hill in your city and climb it again and again: repeats of a short hill still add up to serious climbing.

Descending is the hardest part to mimic in a city, since most treadmills do not tilt downhill. So work the way down your short hills in a controlled manner too, and make room in your plan for stair descents and eccentric strength exercises. For footing skills, use dirt paths and uneven ground in parks. Whenever you can, get to a real trail at the weekend and treat those days as the most valuable long runs of your preparation.

Fuelling, kit and night running: what should you rehearse before the race?

In a run lasting hours, fuelling matters as much as training. The general principle is to start early and keep taking something in regularly, rather than waiting until you are hungry or thirsty. How much and how often varies with the person, the weather and the length of the race, and you only find out which gels, drinks or real food your stomach tolerates by trying them on long runs. Fluid and salt needs rise markedly in the heat. If you have a specific health condition, ask a professional.

Many trail and ultra races publish a mandatory kit list; a waterproof jacket, headlamp, emergency blanket, whistle, phone and a minimum water capacity appear on many of them. The list is not a formality: it can save your life when the mountain weather turns. Read it weeks before the race, fill the gaps and do your long runs carrying that load. Find out in training, not on race day, whether your vest chafes or your shoes crush your toes on long descents.

In longer ultras, running in the dark is often unavoidable. Under a headlamp the ground looks different, depth perception drops and your pace naturally slows. Do not meet night running for the first time on race day: do a few sessions in the dark, ideally on a route you know. Test the battery life, the brightness settings and swapping in a spare battery. Darkness combined with fatigue clouds judgement, so make checking the course markings a habit.

Mountain safety and the most common mistakes

Running in the mountains carries different risks from running in town. The weather can change within hours, sometimes faster; it gets colder as you climb, and wind and rain grow harsher. Check the forecast before you go and carry one more layer than you think you need. Always tell someone your route and when you expect to be back, make sure your phone is charged, and avoid running alone on unfamiliar ground. If the weather turns or you feel unwell, turning back is always the right call.

The mistakes runners make when moving to trails and ultras mostly come from road habits. Most of the ones below are easy to avoid if you spot them early in your preparation.

• Chasing pace on trails and targeting distance instead of time and effort.
• Training only the climbs and neglecting the descents.
• Refusing to walk the climbs and burning energy early in the race.
• Trying fuel, shoes or a vest for the first time on race day.
• Building the long run and back-to-back runs too quickly.
• Running on through persistent pain or after an ankle sprain; if pain lingers, see a health professional.

Frequently asked questions