You’ll be surrounded by nature.
Chipmunks will be flying out into your path. Squirrels will drop nuts and branches on your head. And you’ll most likely swallow a nat or a fly at one point or another. Keep an eye down, as you’ll probably run over a variety of animal feces, too.
You’ll get dirty.
Dirt likes to grasp onto wet areas and make a nice mud mixture. It’ll find its way up your legs, on your arms, and leave a nice reminder that you were outdoors. Don’t plan to go shopping after a trail run, first you’ll smell pretty bad, but people might wonder if you shower at all.
You’ll have to go uphill.
I have never found a trail yet that is completely flat. I swear nature tortures you with rolling hills even when it so easily could be a flat path. Always be ready to go up and down, it’s never flat.
If you’re lucky, there’ll be porta potties.
If you’re on a nice trail, they’ll provide you with delightful bathrooms that the guy before stunk up. You’ll learn to go as fast as you can while you hold your breath. If it’s not provided, well, see a variety of animal feces comment above and watch where you step.
You’ll feel so amazingly peaceful during your run, you’ll want to keep going.
And we know if you keep going more than you should you’ll be injured. Don’t fall prey to the beauty you encounter. It’s a trick.
As you can see, trail running is fraught with huge drawbacks. Ones that’ll make you question why you went out in the first place. You have to lug your own stuff, go potty in the most unassuming places, and be on the lookout for wildlife.
It’s dangerous out there, best keep to the couch where it’s safe and clean.