Trail running is an incredible way to connect with nature while pushing your physical and mental boundaries. Whether you’re a beginner or looking to step up your game, building endurance in trail running is the cornerstone of conquering rugged terrains and longer distances. Here is a detailed guide to help you develop the stamina and strength needed for trail running success:

Establish a Strong Aerobic Base

Before tackling the challenges of trail running, it’s essential to establish a solid aerobic base. Start by consistently running on flat or gently rolling terrain, aiming for three to five runs per week. Gradually increase your weekly mileage, adhering to the 10% rule: avoid increasing your total mileage by more than 10% per week to reduce the risk of injury. Focus on maintaining a conversational pace during these runs, as this will train your body to use oxygen efficiently.

This doesn’t just apply to trail running. Building endurance for any kind of distance means starting small and building up the miles gradually to avoid injury.

Prioritise Long Runs

The long run is the cornerstone of endurance training. Schedule one long run per week, gradually extending its duration over time. Instead of focusing solely on distance, pay attention to the time spent on your feet, as trail running often involves slower paces due to technical terrain.

Begin with a distance or duration you’re comfortable with and incrementally increase it. These runs will prepare your body and mind for the sustained effort required during races or extended trail adventures.

Some people do this by counting the amount of miles they run however, when you are out on the trails, you can focus more on how long you are on your feet for. For longer runs, many tend to walk the hills so getting the time out on your feet is invaluable, especially when training for an ultra distance. Be careful not to increase your mileage too quickly – no more than ten percent per week and include a cutback week every 3rd or 4th week to give your body the opportunity to recover and repair.

If you are increasing endurance to trail for a specific event such as an ultra distance, you can start to do what is called back-to- back runs when you do long runs on consecutive days. We usually do these over a weekend and instead of doing 25 miles all in one go, we might break this down into two 15-mile runs.

Train on Technical Terrain

Trail running demands adaptation to uneven surfaces, steep ascents, and unpredictable terrain. Incorporate runs on trails to develop the skills and confidence needed to navigate these challenges. Running on trails improves balance, coordination, and agility while strengthening stabilising muscles.

Start with less technical trails and gradually progress to more challenging routes as your skills improve. If you are not so confident on the trails yet, try and include some grass – we often do sessions on flat grass to get us used to the more uneven surfaces.

Include Hill Training

Hills are an integral part of trail running, and training on inclines will build both strength and endurance. Add hill repeats to your weekly routine by finding a steep hill and running hard uphill for 30-90 seconds, then jogging back down to recover. Repeat this for 6-10 intervals, depending on your fitness level.

Additionally, practise sustained uphill efforts on long climbs to simulate race conditions. Downhill running is equally important; it strengthens your quadriceps and improves your ability to descend efficiently without overloading your joints.

Don’t be afraid to walk the hills on your longer runs – while it is good to learn to run up hills, during longer ultras, the trick is to not elevate your heart rate too much.

Cross-Training for Endurance and Strength

Cross-training reduces the risk of overuse injuries while enhancing overall fitness. Activities like cycling, swimming, rowing, or hiking are excellent low-impact options that build cardiovascular endurance. Strength training should also be a staple in your routine.

Focus on exercises that target your core, glutes, hamstrings, and calves. Squats, lunges, deadlifts, and step-ups are particularly beneficial. Incorporate balance and stability work, such as single-leg exercises, to mimic the demands of uneven trails. Some of our best runs have come off the back of multi-discipline training cycles.

Add Interval and Tempo Workouts

Speedwork isn’t just for road runners; it’s vital for building endurance on trails. Interval workouts, where you alternate between high-intensity efforts and recovery periods, boost your aerobic capacity and help you manage climbs more efficiently. For example, try running 4-6 sets of 3 minutes at a hard effort, followed by 2 minutes of easy jogging. Tempo runs, which involve running at a “comfortably hard” pace for 20-40 minutes, improve your lactate threshold, allowing you to sustain faster paces for longer periods.

Master Nutrition and Hydration

Proper fuelling and hydration are critical for endurance athletes. During long runs, train your body to consume carbohydrates at regular intervals, such as energy gels, chews, or whole foods like bananas and nuts. Practise drinking water or electrolyte drinks consistently to prevent dehydration. Learning what works for your stomach during training will prepare you for race day. Invest in a quality hydration vest or belt to carry fluids and snacks during your runs.

Incorporate Recovery into Your Training

Rest and recovery are just as important as the training itself. Schedule at least one full rest day per week and consider adding active recovery sessions, such as yoga or light cycling, to keep your body moving without adding stress. Additionally, plan recovery weeks every 3-4 weeks by reducing your mileage and intensity to allow your body to adapt and rebuild stronger. Listen to your body and don’t ignore signs of fatigue or pain—overtraining can lead to injury and setbacks.

Mental Endurance and Pacing

Trail running is as much a mental challenge as it is a physical one. Train your mind to stay focused and positive, especially during tough sections of a run. Practise pacing yourself by starting runs at a conservative effort to avoid burnout later on. Use landmarks or time intervals to break down long runs into manageable segments, helping you stay motivated and engaged.

Gear Up for Success

Having the right gear can make a significant difference in your trail running experience. Invest in trail-specific running shoes that provide adequate grip and protection. If you are struggling to find the best trail running shoes, you will find lots of shoe reviews here but we are big fans of a decent pair of Hoka Speedgoats! That’s our top recommendation for multi-terrain all-around running.

Dress in moisture-wicking, weather-appropriate clothing, and always carry essentials like a map, compass, or GPS watch, especially for longer runs in remote areas.

Familiarise yourself with your gear during training to ensure it’s comfortable and functional for race day or extended outings.

Gradual Progression and Patience

Endurance builds over time, so be patient with your progress. Avoid pushing too hard too soon, as this can lead to burnout or injury. Celebrate small milestones along the way, such as completing your first technical trail or conquering a challenging hill. With consistent effort and smart training, your endurance will improve, allowing you to tackle longer and more demanding trails with confidence.

By following this detailed approach, you’ll not only build the physical stamina required for trail running but also develop the mental resilience and technical skills needed to thrive in this exhilarating sport. Whether you’re aiming to complete a race or simply explore new landscapes, your preparation will ensure you’re ready to take on any trail.