One of the first things many people wonder as they think about trail running for the first time is whether they need trail-specific running shoes. The most common follow-up is: what’s the difference, i.e. what are trail running shoes like? In this post, I will offer my perspective on the first question. In a future post, we’ll look at the latter.
The short answer is that most runners enjoy their time off road more in a pair of trail-specific running shoes than in shoes designed either for road running or hiking. However, the degree of benefit depends a great deal on both terrain and runner. Let’s discuss each in turn.
The Terrain
When someone talks about “trail running,” they could actually mean any of a range of activities. It is therefore helpful to begin by defining the term. As a starting point, let’s consider how ATRA (American Trail Running Association) defines it:
“Although most runners consider trail runs to be strictly an off-road and primarily a mountain experience, our definition of trail runs is fairly broad based to include not only mountain single-track trails but to encompass the oft paved pathways in rural and urban areas. We wrestle with the idea that a trail must deny motor vehicle access for consideration by our association since many out of the way places in the mountains have jeep or four-wheel drive access.”
Based on ATRA’s definition, trail running encompasses an incredibly diverse range of terrain. I have no quibble with this as a philosophical matter; inclusivity is good for the sport. But when discussing appropriate gear, it isn’t specific enough.
When trying to determine the appropriateness of trail-specific shoes, I like to think in terms of “leverage.” The point is to move away from the binary thinking of “trail running/not trail running” in favor of a spectrum. We can further refine leverage as consisting of both physical and technical dimensions.
As you probably suspect, lower leverage terrain has smoother, more predictable surfaces (the technical difficulty dimension) and easier grade changes (the physical difficulty dimension). Foot placement entails little risk of immediate injury. Sustained climbs and descents rarely exceed 5% — 1 foot of elevation change for every 20 feet traveled — and are usually well below this threshold. Examples include natural-surface park paths, rail-trails, and most fire roads, in addition to the single- and double-track wilderness trails that typically come to mind. Per ATRA’s definition, low-leverage trail running may even include paved bike paths.

Low-Leverage Single-Track
By contrast, higher leverage trail running happens on uneven, unpredictable surfaces with significant grade changes, almost always in mountain and other wilderness settings. Primarily, this means double- and single-track where rocks and roots litter the trail. Exposure — the myriad risks associated with being far from help in the face of often extreme natural elements — may be a significant factor. (You know, as opposed to the hazards of sharing a bike path with pre-teens on rollerblades.) Sustained climbs in excess of 5% are common, as are shorter ramps of 15-25% or more.

High-Leverage Mountain Single-Track

High-Leverage Desert Single-Track
The Runner
Athletes who decide to take up trail running bring a range of experiences and expectations to the activity. Common converts include road runners, hikers and backpackers looking to go ever lighter and faster, and multi-sport athletes interested in all forms of human-powered outdoor activity.
The kind of trail running pursued at the outset by a particular athlete will usually be a natural extension of what they already are doing. The road runner is likely to cross over by first mixing some lower leverage trail terrain into his or her current road routine, whereas the lifelong hiker is more likely to tackle difficult terrain straightaway, but probably at a speed only slightly faster than their hiking pace.
Upshot
Now that we have made more meaning of the term “trail running,” it should start to become clear whether trail-specific shoes are a worthwhile investment for the beginning trail runner. If you are thinking about taking only a minor, incremental step from what you are currently doing in terms of terrain, speed, and/or duration, trail-specific running shoes will provide only a limited advantage over the footwear you are currently using. But if you are interested in high-speed, high-leverage trail running, a pair of shoes equal to the task will, for most people, significantly increase both the safety and enjoyment of the experience.
The obvious advice is to try the type of trail running activity most like what you are currently doing, using the footwear you currently use for that activity. If you like it — and, let’s face it, you will — upgrade to specialty shoes, and other trail-specific gear, as you lever up.
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I wore only trail shoes when I first crossed over to trails, but now I find that I let the terrain/footing dictate the shoe choice on any given day. Harder surfaces beg for my cushiony roadies generally, but if there’s snow or ice on top of any surface, the trail shoes come out without question. They rock on slippery surfaces!
I run a lot of high leverage trails and enjoy my trail shoes on those trail. My problem is that I sometimes run 3-4 mile on roads to get to the trail head. Since a major function of a trail shoe is the tread, I rarely wear my trail shoes unless I launch from the trail head without the road work pre-trail. Am I being overly anal about the trail shoes tread? Is there a hybrid Trail/Road shoe that you can recommended?
Thanks for your hard work, I look forward to new articles!
General note: A very few of you may have experienced déjà vu with this post. That’s because it was originally published last year in the old “Owner’s Journal” (as was its forthcoming part two). In the WordPress transition, I elected to re-publish a few items (with minor editing) instead of moving them over with the old date where they would have been somewhat buried among other topics.
Paige: Your approach sounds pretty similar to my own. Terrain is probably the biggest single consideration for me when choosing which shoe to sport. More about this in the second post on this topic.
Bob: Going from one extreme to another — from pavement to high leverage trail — does present a bit of a shoe-selection challenge for many runners. My two cents. I wouldn’t worry about taking your trail shoes on pavement, if you can stand the stiffer ride. There’s definitely no need to “baby” them. In general, their mid and outsole are much denser and more durable than road shoes. But the stiffer ride can be annoying if you’re covering more than short distance. Among the shoes that are legitimate trail shoes but are a bit softer and more road-like in their feel are: Brooks Cascadia, La Sportiva Wildcat, Salomon XT Wings, and Vasque Blur SL. Hope that helps a bit. Do stay tuned for the second part of this discussion, since it will get into the differences between road and trail shoes, and among the different types of trail shoes.
That photo of “High-Leverage Mountain Single-Track”? Looks a lot like the TRT. Just in case you were wondering.