Trail RunningTraining

Capacity Training: A Foundation for Successful Trail Running


Trail running is a multifaceted sport that requires a harmonious blend of endurance, speed, technical skills, and mental strength. One of the primary building blocks of this skill blend is capacity training or base training. But what does capacity training entail, and why is it so critical for trail runners?

The Science Behind Capacity Training

In physiological terms, capacity training aims to maximize the body’s ability to transport oxygen from the lungs to the muscles during prolonged exercise. The two primary ways to do this involve increasing the volume of blood the heart pumps with each beat (stroke volume) and the volume of oxygen your muscles can extract from this blood (a-vO2 difference). Training at or below your lactate threshold – the intensity at which lactate starts to accumulate in your blood – helps to improve both.

The other part of this equation is enhancing your body’s ability to use fat as a fuel source. Fat is an abundant energy source, even in the leanest athletes. Training at lower intensities encourages your body to become more efficient at using fat, preserving precious glycogen stores for higher-intensity efforts.

Periodization and Capacity Training

Periodization is the practice of varying training stressors over time to maximize performance and minimize injury risk. Capacity training typically forms the first phase of any periodization plan. It aims to enhance aerobic fitness through steady, comfortable runs, as well as build running skills and strength.

  • Speed Skill: The incorporation of strides and hill sprints in your training plan can significantly enhance your speed skill.
  • Trail Skills: Regular practice on uphill/downhill running and maneuvering through technical trails aids in trail skills development.
  • Proprioception: Balance and agility ladder drills help improve coordination and body awareness.
  • Strength Work: Regular strength and core workouts are vital for running efficiency and injury prevention.

Think of Capacity training as training to be fit and skilled enough to do the race training, which typically happens in the last 8 to 10 weeks before your event. The reason this phase is kept to less than 12 weeks is that not many people can sustain the intensity required for race prep beyond 12 weeks. So your capacity training will have taken into account the skills, energy systems, and fitness you’ll be needing in your main event.

Race training then is taking the capacity you have built and using it with race-specific training to get you into the best possible shape for racing. Many people don’t ever progress beyond capacity training and that is fine because 80% of your result is based on that capacity. But remember, layering the final 20%—race-specific training—on top of that 80% is a recipe for real success.

Too much emphasis is placed on fancy-looking workouts and optimizing the top 5% of the fitness continuum when the 80% which is capacity training hasn’t been maximized. Don’t fall into this trap, concentrate on building a strong foundation first.

In essence, capacity training is about laying a solid foundation of fitness and skills upon which more specific race preparation can be built. For trail runners who can only access trails on the weekends and have to train on roads during the week, this phase provides an opportunity to maximize their time on trails, focusing on runnable trails to improve running skills and limit walking. This makes capacity training an invaluable tool for all runners, regardless of their race goals.

Remember, each run or workout you do during this phase has a purpose, and understanding that purpose is key. Building capacity isn’t just about accumulating mileage, but also about enhancing your overall skills and strength as a runner, preparing you for the race training that lies ahead.

If you’re looking for someone to guide you to your best result then take a look at working with a Mindful Runner Coach