If you are interested in trail running, you should probably own a shoe designed specifically for running on the dirt. Trail running shoes are constructed with features that road running shoes don't have, and these features add the safety, protection, and durability needed to tackle the unpredictable terrain you will encounter when you venture off the beaten path.

So what specific elements make up a trail shoe? Although not all trail shoes have the same features (since not all trails have the same features), if the shoe you are looking at has one of the following four attributes listed below, chances are it's made for running trails.

When you hit the trail, rocks, branches, and other natural debris will hit you back. Having a durable upper is essential, both for the longevity of the shoe and for the protection of your feet. Many trail shoes are built with tear-resistant uppers to withstand anything the trail might throw at your shoe. One of the reasons you don't want to run in road shoes on the trail is that the materials of road-specific uppers are not designed to be as durable for handling abrasions and tears.

Like treads on a tire, the outsole of your shoe helps determine what kind of grip you will have on the surface you are running on. Trail shoes typically have deeper, more pronounced lugs on the outsole than road running shoes, providing more traction between your foot and the ground. Lugs will vary in size, shape, and depth. For a harder trail, you will want shallower lugs, and for softer, muddy trails, you should go with deeper, aggressive lugs for a more solid grip to avoid slipping.

Equally important is the spacing of the lugs. Lugs positioned farther apart from each other will allow mud to shed off from the bottom of the shoe, preventing it from accumulating and weighing you down. Conversely, more closely spaced lugs are suitable for rocky, dry trails and will offer you more stability and efficiency.

To help protect your toes from any rocks or debris that your feet may encounter on your run, running shoes are built with reinforced material at the front of the shoe. Trail shoes generally have a larger or more durable toe bumper than road shoes to prevent breakage, stubbing, or bruising of your toes from tree roots, jagged rocks, and stones.

Some trail shoes contain a rock plate, a material embedded between the outsole and the midsole of the shoe for underfoot protection. The rock plate may add a bit of stability and stiffness to the shoe, but more importantly, it helps protect the soles of your feet from sharp rocks and stones that you may run over. This helps to eliminate the painful ouch factor, especially on technical trails. In turn, the rock plate allows you to pick up the pace without worrying about injuring your feet on rugged terrain.