Runners are famous oversharers about all the shit — literal and otherwise — that happens when you run: All the bodily sweat, smells, secretions, excretives, discharges and other nastiness that your corporeal self does in response to you running hard. For the love of God, TMI already!
But there’s a lower-key, ongoing debate among runners along these lines, or at least, in this same bodily region: Are you supposed to wear underwear when you run? Some runners swear off underwear, while others doggedly stick to it with the relentless determination of a clingy elastic waistband. Can they both be right? What are you really supposed to do?
Alongside Mario Fraioli, a running coach and creator of The Morning Shakeout, a running newsletter and podcast, we’re freeing up some answers.
Wait… some people run without underwear?
Oh, totally — in fact, you could say it’s a bit like broccoli. People tend to know where they stand on the topic, and swear by their decision. In a sense, it might also be one more element of gatekeeping that hardcore runners use to delineate themselves from the rest, though Fraioli personally doesn’t see it that way.
The thing is, that lining you find in many running-specific men’s shorts is truly designed to be worn without underwear. It’s an extra layer between your body and the outer short, it’s supportive enough to prevent, well, all that could go wrong, and it’s designed to be all you need. As long as it’s operational, it’ll keep everything in place.
How am I supposed to know this?
True — it’s not written anywhere on the short, and the hangtag never says anything like “no underwear required” or “do not wear underwear while using this product.” A lot of longtime runners just sort of picked up on it at some point.
“I remember my senior year [of high school cross country] I was given a pair of real running shorts with the built-in liner inside, and I put them on over my boxer shorts, and it just became clear to me that that wasn’t how they were meant to be worn,” Fraioli says. “It took a little getting used to, but then you realize that everything stays intact, and it was a more comfortable experience — I’ve just stuck with it ever since.”
Is it gross?
Well, there’s a reason the liner in running shorts is often silky smooth and made out of quick-drying material. So no, it’s no grosser than what running does to you anyway. A lot of people vastly prefer it to wearing underwear.
But there are people who insist on wearing underwear even after figuring this out?
Yes — this is definitely a thing, Fraioli says. “I do know of a few runners, most of them newer runners, who will wear some type of underwear under running shorts that have a built-in liner. And more and more companies these days are offering at least an option of linerless running shorts, so that runners can choose what they want to wear underneath.”
He points out that there are companies who also make running-specific underwear. Either way, it’s mostly a comfort thing, he says. “I’ve asked people who do wear underwear with their running shorts why, and they say it’s more comfortable, which I don’t understand, but if it’s comfortable for them, go for it.”
So is wearing underwear with running shorts a bad thing?
Not really. The downsides are that it’s one more thing that’s clinging to your body as you’re moving and sweating hard, which means it could chafe your skin. And you’re just adding in an element that the product wasn’t designed around. It’s perhaps a bit like the guys who wear underwear under swim trunks, and pretty much harmless.
What about the laundry factor?
Yeah, you might be able to get another run in some shorts you’ve previously worn with an underwear barrier before having to wash the stank out. Fraioli says that’s not necessarily the case for him — a decent rinse in the shower followed by air drying buys him a couple runs in a pair of shorts between washes. “Maybe because you’re not sweating on the garment [your shorts] last longer, but then you’re washing your underwear more often,” he says. “So I don’t know — I think that’s a wash, no pun intended.”
But the shorts, then, are only as good as the liner?
Kinda, yeah. The liner will stretch out after a while, and Fraioli says you can always tell when they’re too far gone. If you’re running without underwear, once the liner goes, so too should the shorts. Or, you could just start wearing underwear.
What about tights?
Again, it’s all personal, though you’ll tend to find more guys wear underwear with tights, particularly when it’s really cold. Some tights have liners in them, some don’t. Even if tights feel fairly supportive, one major consideration — let’s be honest — is the silhouette factor. Tights don’t hide much! At least, less than some people would like. Then there’s also the sweat factor, and that extra layer, whether it’s via a liner or underwear, is pretty important in keeping you dry everywhere (both for looks and for comfort).
Either way, though, you’ve gotta have some support, right?
Oh yeah — if you run truly freebird, prepare to face the consequences — which are awful. “I definitely wouldn’t advise it!” Fraioli says. “A male runner definitely needs some kind of support. In my experience, most lined running shorts provide an adequate amount. If you don’t run in traditional running shorts or you wear one of those models that comes without a liner then yes, you should wear some sort of brief or boxer brief underneath to keep everything intact.”
Whatever you end up doing, though, it’s probably better for your balls than cycling.