
What Is Trail Running?
A very basic but necessary first question. According to the International Trail Running Association (ITRA), Trail-running is a pedestrian race open to all, in a natural environment (mountain, desert, forest, plain…) with minimal possible paved or asphalt road (which should not exceed 20% of the total course). The terrain can vary (dirt road, forest trail, single track…) and the route must be properly marked.
Trail runs are on-trail activities in both semi-urban and backcountry areas, usually moving at a faster pace and with an emphasis on traveling light. They require a mix of skills for traveling across various types of terrain; anything from paved streets to forest service roads or single-track trails of dirt, sand, stone, snow, or another material.
The race is ideally – but not necessarily – in self-sufficiency or semi self-sufficiency (meaning that the runner has to be autonomous between aid stations, regarding clothing, communications, food and drink) and is held in the respect for sporting ethics, loyalty, solidarity and the environment.
Trail running is a popular activity for the summer season. Contrary to popular belief and widespread notions, you don’t have to have mountains for trail running. Trail running can in fact be done everywhere. It is considered a “trail run” when you are not on surfaced, paved, sealed or asphalt roads. For trail running, it’s all about the movement outdoors in nature in fresh air.
While for road running or on sealed paths, standardized values such as distance, running pace or heart rate are frequently the focus, for trail running the experience itself takes center stage. The obstacles and the terrain are constantly changing – first you’re on rocks, then on grass, occasionally over roots, and in between it may go up and then go down. On a trail, both your body and soul are alert and challenged.
Trail running is probably one of the most liberating sports out there. The total freedom of stepping off the pavement and onto countryside footpaths is an experience that everyone should try at least once. I grew up running trails as a child. Living in the remote areas of South Wales with no public transport or even street lights in our village, running on trails was part of my everyday life, just a quick way to catch up with my friends at the beach or getting home in time for dinner. Roads and pavements in towns are getting busier as more people live and work in urban areas, particularly London. This combined with the increased popularity of running and cycling to and from work as well as at lunch times makes for busy pavements. If you are tired of running the same old route or losing your mojo to pound the streets. Perhaps it’s time to have a look at trail running to escape the crowds and get back to the true freedom running provides.
Where To Run?
The route options are limitless and all within just a few hours from London; from the wild areas around London, like the Chilterns and South Downs to the Alps in France. The key thing is to have an adventure and really enjoy your running. Don’t forget that over 80% of the UK is considered to be ‘rural’. You may be surprised at how near you are to finding some trails, even if it requires some effort to get there, it is certainly worth your time.
Is It Good For You?
There are many health benefits to trail running, improved plyometrics and proprioception, stronger core as well as less impacts on joints. It’s also a very easy way of burning calories whilst having fun! But preparation for trail running is just as important as heading off on the roads or track. Building up core strength as well as overall strength conditioning is key to remaining injury free and getting the most out of your runs. Getting into trail running is easier than you may think and a countryside path, or trail around a city park is a good place to start. These changeable surfaces can build up strength and refine your technique, avoiding the more repetitive actions of road running, but trail running can be a stimulating, 3-dimensional experience. Watching out for the different surfaces, steep ups and downs, the scenery, the peace and quiet, all add to an experience that is both mentally and physically challenging.
History

Since the mid-1990s, the popularity of trail running has grown at a rate of 15% each year for the past decade and the future looks even brighter as new countries and entrants discover the joy of running in the environment, with the current estimates at 20 million trail-runners worldwide. The International Trail Running Association (ITRA) was founded in 2013, with the aim to promote trail running around the world and give voice to all parties involved in the sport. In 2015, trail running was recognised by World Athletics as a discipline of athletics. Today ITRA is World Athletics’ partner for the management of trail running worldwide.
It is difficult to pinpoint the exact birth date of trail running; however, the first organised races took place in the United States in California with the Dipsea Trail Race. The Western States 100 Mile Endurance Run (1974) and Leadville Trail 100 (1983) are also among the pioneers of this sport, followed closely by the Marathon des Sables in Morocco (1986) and the Grand Raid de La Réunion (1989).
Trail running experienced a boom in the 2000s in Europe with the first edition of the UTMB® in 2003, then followed by many other races. Today trail running is quickly expanding into Asia and South America and has become one of the fastest growing sports in the world.
Difficulty Ratings
Difficulty ratings for trail running routes use the following scale as a general guide. Leaders may set a route’s baseline difficulty rating to a higher difficulty level to reflect trail conditions or the need to use equipment such as traction devices.
- Easy – Up to 5 miles round trip with less than 1,000 feet of elevation gain or a moderate trip with an average pace of 3-4 mph or slower. Easy runs are not held in darkness and do not require equipment such as traction devices or poles.
- Moderate – Up to 10 miles round trip or with 2,000-3,000 feet of elevation gain or a strenuous trip with an average pace of 3-4 mph. Trail runs which would otherwise be categorized as Easy but that do require equipment such as traction devices or poles or that are held in darkness are listed as Moderate.
- Strenuous – Up to 15 miles round trip or with 3,000-4,500 feet of elevation gain or a very strenuous trip with an average pace of 3-4 mph. Equipment may be required, and the trail run may be held in darkness.
- Very Strenuous – 15-20 miles total or over 4,500 feet of elevation gain, or a shorter mileage/smaller elevation gain trip with an aggressive pace. Equipment may be required, and the trail run may be held in darkness.
- Ultra – 20-31 miles total which does not fall under Advanced Ultra 1 as described below. For all Ultra categories equipment may be required, and the trail run may be held in darkness.
- Advanced Ultra 1 – 20-31 miles total which will be covered at an aggressive pace, has an exceptional level of difficulty or remoteness, or requires significant technical skills and equipment.
- Advanced Ultra 2 – 32-50 miles total with has an exceptional level of difficulty or remoteness, requires significant technical skills and equipment, or will be covered at an aggressive pace. Or any trip 51 miles round trip or longer, even if held in a non-backcountry setting.
Leader Ratings
Each trail run is additionally given a leader rating by the trip leader. This leader rating is meant to show participants how the trip leader intends to lead the trail run. Leader ratings include:
- For Beginners – Average pace 3 mph or slower counting any rest breaks but not counting a lunch break or a planned pause for instruction and skills practice. No technical challenges are present and no equipment or special skills are needed. Run is not held in darkness.
- Easy -Average pace 3-4 mph and no technical challenges are present and no special skills are needed.
- Moderate – Average pace 3-4 mph or an easy route with a heavier pack due to logistical requirements, such as the need to carry extra water and supplies, or some route challenges (e.g. rough trail, log crossings, steep terrain, crossing a talus slope).
- Challenging – Average pace greater than 3 mph or a trail run rated as Moderate done with a heavier pack that the leader plans to lead in a challenging fashion, or significant route challenges or skills requirements (e.g. fixed ropes, very rugged terrain, steep scree descents, snow crossings; mandatory use of traction devices). Challenging applies to all routes rated as Strenuous, Very Strenuous, and Ultra. Challenging also applies to organized races/events where participants aim for maximum speed and must negotiate the trail with others participating in the same event.

Technique For Trail Running
Imagine a fast running form. What do you see? For most people, the first thing that subconsciously gives away “speed” is quick turnover—a high cadence built to withstand many miles. The strides are soft and quick, with strong rearward kick. The person is running tall, with good posture and arms held closely to the body. And most of all, he/she probably looks relaxed and comfortable.
That ideal form is not just genetic, though it does have genetic components. By practicing form every day on your run, you can improve. And by improving your form, you can improve your running economy for the long haul. Let’s start from the feet and work up.
Foot Strike
To overturn one misconception: there is no perfectly ideal place on your foot to first make ground contact. Some swear by running on your toes and others on your mid-foot, but all that really matters is where your foot strikes in relation to your center of gravity. The key is to avoid over striding by having the foot land under the mid-line in your hips, rather than slightly in front of that mid-line.
For many runners, that essentially means that landing “flat-footed” is ideal, which will usually feel like a mid-foot strike, but if you slow it down using a camera, you’ll see what we mean. The body wants to maximize the surface area underfoot at impact. Heel striking is often (but not always) associated with over striding. Toe striking is active, rather than passive, requiring a pointed foot that uses excess energy.
To achieve the ideal foot strike, relax your feet and ankles and take short strides that fall under your center of gravity. The landing that results will likely be ideal for your physiology.
Stride Dynamics
While footfall is mostly passive, stride dynamics are an active set of choices you can make every day you go out on a run. Let’s start with the general and work toward the specific using a three-point strategy.
First, your strides should generally be soft, which usually means your form is more efficient. Listen to your footfall when running. Does it sound like a light pitter patter, or like a person playing the drums too loud? Ideally, you are quiet enough that you can sneak up on people like a ninja without them knowing you are there.
Second, your strides should be quick, which distributes load more efficiently over the course of a run. Often, it feels a bit unnatural at first, especially for people with a background in sports that involve sprinting. As a sprinter, you learn to practice long, powerful strides. As a trail runner, you want short, rapid strides.
Third, you should learn to target a running cadence that works best for you. There is no right answer for this. Most elite runners are around 180 strides per minute, and almost all successful runners are above 170 strides. However, there are exceptions. Trail-running superstar Jim Walmsley is notorious for his loping stride that is closer to 165, practically unheard of among fast runners.
While there is no right answer, most trail runners would be well-served to practice a soft, quick stride that is at least 170 strides per minute. A way to measure your stride rate is to count how many times your right leg hits the ground in 30 seconds. Multiply that number by four for your stride rate.
Engage the Glutes and Practice Good Posture
Glute engagement is about running form, rather than focusing specifically on what your butt does. A three-step process can be helpful to figure it out.
First, stand up. Most people will have tight hip flexors when standing. So, think about loosening the hip flexors and activating your glutes slightly. Your hips should move forward and your spine should straighten. That is the posture to use when running.
Second, when running, think about that relaxed-hip-flexor posture, then focus on flowing back, rather than pulling forward. The moment of power in your running motion is when your foot pushes off the ground behind your body; maximizing push-off comes from relaxed hip flexors that allow a full range of motion, not a flexed butt.
This rearward flow through push-off is most evident in elite road runners, who usually have a strong back kick. Meanwhile, many recreational runners look more like they are riding a bike, with pronounced forward motion.
Third, to really understand glute engagement, do a fast set of strides on a slight downhill. The best downhill runners have mastered that relaxed-hip-flexor, flowing-back running form. While accelerating, try to stay relaxed and get as close to top speed as possible without sprinting. Then, apply that form to the rest of your running, including at slower paces and on variable terrain.
So when people say, “Engage your glutes,” perhaps they should say, “Relax your hips and practice good posture.”
Arm Swing

A good runner is like a T. rex—ferocious from the waist down and neck up, but unimposing in between. Your arm swing is meant to counter the motion in your hips to preserve balance, not to propel you forward. The most efficient way to do that is to make like a T. rex and keep your arms close to your body.
While studies have not found an optimal arm angle, start at 90 degrees. The key is what comes next. Focus on keeping your arm angle at 90 degrees or less throughout the arm swing—in other words, if you draw a line from your shoulder to your elbow to your wrist, it should form a right angle. Don’t let your arm angle open up.
If you watch many efficient road and track runners, their arms often form even shorter levers, sometimes around 70 degrees. By keeping the angle at 90 degrees or less, the arm swing uses less energy, which can then be used where it’s really needed—in the legs.
To put it another way, T. rex arms are essential for Velociraptor speeds.
Uphill Technique
Running uphill can be pretty darn horrible.
The social-media accounts of professional runners (or even normal people with very short memories) may claim that running up steep grades is “awesome” or “epic.” But no amount of heavily filtered photos can hide the truth: If we were meant to run uphill, we would all weigh 100 pounds and be born in a hut in the Spanish mountains like Kilian Jornet.
So, yes, gravity can be a jerk. But you can make it your friend. A few simple techniques make every uphill a breeze … well, easier.
Lean Forward
The main thing to focus on when running uphill is to lean into the ground and use your forward momentum.
First, look down at the ground in front of you (which you should be doing anyway to watch your footing on trails). Second, tilt your center of gravity forward, aiming to mirror the gradient beneath your feet. For example, when on a 10-percent grade, think about leaning 10-percent forward from center. On steeper grades, go even farther forward.
Finally, when running with this technique, think of your legs less as powerful pistons, and more as tools to keep you from falling face-first into the ground. With each step, your momentum while leaning forward will carry you up the mountain—your legs merely keep the forward motion going.
This technique takes practice, but staying too upright is the number-one mistake that most self-proclaimed “bad hill runners” make. Concentrating on leaning forward is the first step to becoming a mountain goat.
Relax
Running uphill, tension makes every step harder, forcing you into a hike that much sooner. But relaxing is a simple two-step process. First, and most importantly, focus on letting your leg muscles loosen whenever your leg is not in active contact with the ground. The step-to-step cycle of contract-loosen-contract-loosen will delay accumulation of fatigue in your legs and allow you to push longer.
Second, while leaning forward, concentrate on letting your lower back and arms release tension. A slight forward lean on uphills can immediately be counteracted by a lower back that springs you upright every chance it gets. And flexing arms are using up blood that should be going to your legs and lungs.
Power Hike Strategically
Hiking is the dirty secret of the trail-running world. You almost never see a magazine cover with someone walking. But like pooping, everyone hikes, even the pros!
That said, there is often a massive difference between how people hike. And that difference can turn something fast and efficient into a waste of time. So how do you hike with a purpose?
First, as with running uphill, lean forward. Even farther forward. Even farther. Perfect. When power-hiking uphill, you want to feel like you are almost parallel to the ground (even if you are actually not even close).
Second, focus on using your arms. The ideal technique is to place your hands on your quadriceps closer to the hip than the knee. Each time your leg pushes off, use your arm to push down and give you an extra lift.
Finally, alternate uphill running and purposeful hiking for maximum efficiency. Like running uphill, power hiking is hard, and mixing it up will allow you to go farther, faster. A good breakdown is 10 seconds running, 50 seconds hiking, but any mix can work. Adapt to the terrain, hiking on steeper gradients, and running on flatter ones.
As for when you should start hiking, that is a personal choice based on your fitness level and background. Experiment with what works for you. Some people should be hiking whenever the trail goes up; others might never need to hike unless the trail almost requires rock-climbing ropes. A good rule of thumb for long runs or races is to hike any hill when you cannot see the top.
Downhill Technique

One of the toughest things for new trail runners to learn is that moving fast downhill requires two different types of running form. Let’s call them the angry hippo and the dancing mountain goat.
Non-Technical Downhills
The hippo is best on slight downhills without too many big rocks or girthy roots, such as fire roads or typical Northern California trails. On these hills, the most efficient form is one that eats up the ground with slightly longer strides. A slight heel strike is natural on these downhills, but try to land as flat footed as possible to distribute the load away from your knees and toward the big shock system in your quads and butt. To train your musculoskeletal system, do relaxed, 30-second strides on gentle downhills, emphasizing a powerful stride and rearward hip extension that engages your glutes.
Steep and Technical Downhills
The mountain goat is reserved for the steep, rocky descents common in Europe, Colorado and much of the eastern United States. Imagine a vertical line drawn from your hip bone to your ankle, and try to keep it from moving forward or backward. Run with short, choppy strides, raising your knee rather than kicking back powerfully. This technique will lead to a soft, high-cadence stride that reduces impact while lessening the risk of tripping. To practice, there is really no substitute for finding steep, technical hills and running down them as often as you can.