Which trail running shoes do you need? How to choose by fit, lugs and cushioning

Which trail running shoes do you need? Walk up to a wall of trail models for the first time and you can soon feel overwhelmed: lugs, stack, drop, rock plate. Good news: four things decide almost everything. How the shoe fits your foot, how deep the lugs are, how much cushioning you want and how much protection your terrain demands. And that terrain is surprisingly varied in Belgium: muddy paths in the High Fens in November, stones and roots in the Ourthe Valley, a mix of forest track, gravel and asphalt in the Sonian Forest, sand in the Kempen. If you know where you run most, you've already done half the work.

What types of trail shoes are there?

Trail shoes fall roughly into four families. Pick the family that fits your outings first; the rest is fine-tuning. ^[1]

If you're a beginner, you'll usually be choosing between the training shoe and the all-round shoe. You only buy a racing shoe once speed becomes your goal.

How do you choose the right fit?

Fit comes first, because no other feature will save a shoe that doesn't fit. Many runners start at about half a size up from their usual size, with a thumb's width of room for the longest toe, because feet swell on a long outing and your toes slide forward on a descent. Treat that as a starting point, not a rule: in the end, choose the size where your longest toe has room, your heel stays put and your foot isn't squeezed. Check three things: your heel doesn't slip, your toes can spread and your midfoot sits firmly. Try on both shoes with your own running socks and test a descent: your toes shouldn't hit the front. If they do, try another size or another model. ^[1]

Then the shape of your foot. Men's shoes usually come in width D, women's shoes in width B. Women often have a narrower heel and a wider forefoot, and some models differ between the men's and women's version. A 2022 study found hardly any effect of sex-specific design on running biomechanics, but fit remains decisive. A shoe is like a jacket: the size is sometimes right, but the cut isn't. If you have a wide forefoot, also try the men's version or a wider fit. If you have a narrow heel, try the women's version. ^[6]

How much cushioning do you need?

Cushioning determines how soft or firm the shoe feels under your foot. Stack height tells you how much sole there is under the heel and forefoot, like the thickness of a mattress. That's not the same thing: two soles of equal height can feel very different. So don't just compare millimetres, but also comfort and control on your usual terrain. ^{[1] [2]}

In practice: for an hour in the woods, an ordinary sole height is plenty; for long days in the Ardennes, a thicker sole becomes more interesting. A low sole gives a more direct feel for the ground and sits more stably on rocky terrain, while a thick sole absorbs more. If you want a direct feel, go lower. If you do long days, go higher. In both cases, test on a descent to see whether the shoe stays stable. ^{[1] [3]}

High or low drop: does it change how you land?

Drop is the height difference between heel and forefoot, like a small heel in the sole: 32 mm under the heel and 26 mm under the forefoot gives 6 mm of drop. That changes the position of your foot in the shoe, but doesn't automatically decide whether you land on your heel or forefoot. In a randomised trial of 59 runners, running mechanics did not change in the long term with 10, 6 or 0 mm of drop in standard cushioned shoes. So don't choose a low drop just to change your running style. Start with a shoe that feels good and with the drop you're used to. ^{[2] [10]}

Comfort can differ, though. RunRepeat's guide to drop says that many runners who land on the heel, and runners with a sensitive Achilles tendon or sensitive calves, often find a higher drop more comfortable, and that a lower drop often asks more of the calves and Achilles tendon. Treat that as a tendency, not a rule. If you want to try a different pair, start with short loops and alternate with your familiar shoes. Watch for new symptoms in your foot, calf or Achilles tendon, and don't also ramp up your running distance sharply at the same time. If you already have complaints, discuss the choice with a sports doctor or physiotherapist: a higher or lower number on the box is not a treatment. ^[9]

How deep should the lugs be?

Lugs are the knobs under your sole, like the tread of a winter tyre: the softer and slicker the ground, the deeper they need to be. The choice is simpler than it seems, because your terrain decides: ^{[3] [5]}

Why does the space between the lugs matter so much? If they sit close together, the sole fills with mud and after a kilometre you have a smooth plank under your foot. Shallow lugs of about 2 mm barely bite into mud. If you're torn between two treads, pick for the terrain where you run most often, not for the one muddy race a year. ^{[4] [5]}

Is soft rubber better?

Rubber is the material the lugs and sole are made of. Many runners think soft rubber grips better and wears out faster. In a lab testing more than 200 shoes, there was no strong link between wear resistance and grip. Grip depends more on the quality of the rubber and on the design of the sole: how much of the sole is covered and what the lug pattern looks like. Rubber hardness is measured with a durometer, grip with a SATRA TM144 test machine on wet concrete. So that tells you something about wet, hard terrain and not about mud or roots. In practice: two shoes with equally deep lugs can still grip differently. Look at coverage and pattern rather than the word "soft" or "hard" on the packaging. ^[5]

When do you need a rock plate, toe cap and sturdy midsole?

A rock plate is a thin, stiff layer in the sole between your foot and the ground. It works like a piece of cardboard under your foot on a pebble beach: you feel the points less. For rocky paths, a package matters: a toe cap and reinforcements in the upper, a sturdy midsole (preferably with a rock plate), moderate lugs with rubber that grips well and a fairly low, stable sole. For example: in the Ardennes valleys with stone and roots, that package pays off. If you mostly run on soft forest paths and gravel, it matters less than fit and lugs. In the shop, check whether the shoe has a plate: press with your thumb under the forefoot and flex the shoe. ^[1]

How much should a trail shoe weigh?

Weight is given in grams on the label. Racing shoes are built light, training shoes emphasise cushioning and durability. In the shop you barely feel the difference, but after two hours in the Ardennes you do: as with a backpack, grams only count when you get tired. Always compare weight in the same size, because a shoe in size 45 weighs more than the same shoe in size 39. Lighter is only better if you don't give up protection your paths need. ^[1]

Which shoe suits you? Three example runners

Three made-up runners. Recognise yourself? Then you'll see straight away how the choice plays out.

Lotte, a beginner in the Sonian Forest. She runs 8 km twice a week on forest track and gravel. Her paths are friendly, so no rock plate or mud tread needed. Choose: an all-round shoe with moderate cushioning and lugs of 3 to 4 mm, in the size where her toes don't hit the front on a descent. ^{[1] [3]}

Karel, 90 kg, first 25 km trail in the Ardennes. In October that means mud and stones along the river. His weight doesn't automatically decide which sole height feels good. Choose a pair that fits, with deeper, widely spaced lugs and a sturdy front, and test it beforehand on a descent. ^{[1] [4] [7]}

Femke, wide feet. She runs 12 km on sandy paths in the Kempen and feels her forefoot squeezed in most women's shoes. The terrain is easy, the shape of her foot is not. Choose: lugs of 3 to 4 mm and the version where her toes have room, even if the label says "men's" or "wide". ^{[1] [6]}

When do you replace your trail shoes?

The well-known rule of 500 to 800 km has an unclear origin and little scientific support. A 2017 study found that midsole material can harden after just 160 km, while runners barely noticed. You only notice a change in cushioning at a difference of about 10%. So replace your shoes when comfort drops, with pain or discomfort, and when performance gets worse. It's a bit like a mattress that looks fine but no longer supports your back. Note the kilometres per pair and look at the lugs: if they're visibly lower than when the pair was new, your grip changes too. ^[8]

Tight budget or second-hand: what do you look for?

On a tight budget, spend your money in this order: first a shoe that really fits, then lugs for the terrain you run most often, and only after that extra protection. A well-fitting pair from last season or a barely used second-hand shoe beats a new one that pinches. A short test run tells you little with second-hand, because a hardened midsole is hard to feel. Ask how many kilometres the shoe has already done, measure the lugs and look for parts coming loose and tears in the upper. ^{[3] [8]}

How to start this week

Ready to start? Think about which terrain you run most often, take the checklist to the shop and run down a slope in both shoes. Then plan a first outing of 5 to 8 km on a path you know, for example a route from RouteRadar, and build up gently. Let someone know where you're running and slip your phone in your pocket. Then autumn in the woods becomes mostly one thing: fun.

Field notes · Route library