Personally, I don't care what I wear when I am doing my running, so long as I am comfortable and it doesn't hinder my workout. And my clothes are really ugly because most of those that I am comfortable to wear when I am exercising don't really look good. They look like floor rags, but I don't care so long as they are not that revealing. Besides, I find them good company for my workout, so why bother?
It's usually just shorts, a t-shirt, and maybe a hoodie if it's cold out. I don't particularly care what I wear when I work out, and I don't really care if people are judging me. If they're there to judge me, then they're wasting their running or gym time.
Personally, I don't find wearing your best tshirt or clothes to the gym to be worthwhile, if you are planning on sweating heavily anyway. As you say, wearing anything as long as it doesn't hinder your workout and is also up to the dress standard of the gym is fine for a workout. You don't go to the gym to make a fashion statement, you are going to exercise so I don't see a reason why it should matter how well you dress. Although dress standards do matter if it negatively impacts other people working out around you, such as unclean clothes. After a workout, the clothes go straight into the wash anyway so this isn't a problem most of the time.
To some extent, outfit does matter when exercising. I mean, I can't just wear dark clothing. Once you get too sweaty, the sweat will cling to the clothes and leave white traces all over. Also, I avoid baggy pants and loose shirts. They're not particularly comfortable to wear compared to spandex or stretchable figure-hugging clothes.
I wear very old, comfortable clothing when I go on my walks. I used to belong to a couple of gyms, and cared a little more about what I wore then, but now I'm usually outside in nature, with like-minded people. There are a few I see on the trails who dress up to work out, but most of us wear whatever suits the weather, and fits and feels good.
Comfort is the most important thing, but I also like to look presentable just in case, but I would rather wear a t-shirt that doesn't ride and a pair of yoga pants that have good stretch in them, than designer matching pieces. As most of my things are black, they do match so I don't have to think about any clashes, only a VPL.
Mostly the same rule that applies to my everyday wear: I MUST BE COMFORTABLE FOR WHATEVER I AM DOING. Obviously, this rules jeans and a tank top out, but anything I can freely move it and won't get in the way. Like someone else mentioned, I can't deal with dark clothing. Makes me get hotter quicker (and not hotter in the good sense) LOL
I don't really mind wearing any old rags when I work out at home, when I go to the gym it's a slightly different story. Even though I don't care about appearances I at least like to look decent when I go out. I don't wear anything flashy, just a simple t-shirt and shorts, but ones that are in good condition.
I'm not one for expensive workout gear either. As long as I am covered, clean and comfortable I'm happy! I really don't think anyone at the gym pays a blind bit of notice to what I've got on anyway - surely they are too busy with their workouts?
I would like to say no, but that's really not the case for me personally. Outfits have a little to do with my overall mood when exercising. Putting on a good, well-fitting, and appropriate exercise outfit when going out can make you feel enthusiastic and not have to worry about your appearance while working out, which is a little shallow, I grant you that. Also, a good outfit doesn't hinder your routines so it also saves you the hassle.
I think that outfit does matter when you go out to exercise. Not for other people, but for yourself. depending on the whether, the outfit that you wear is going to improve or hinder your ability to work out in the way that you want to. Of course, if people want to wear a certain look just so that they can feel good about themselves, rather than wearing it to be practical, then good for them too.
I prefer to not look like a hobo when I exercise, so I do put some thought into my exercise attire. I purchase higher end workout clothing, mostly focusing upon functionality with a little dash of design. If I spend that much money on workout clothes, then I can't afford to just let those clothes sit there, so I guess they help me work out!
I'd have to say, to me it matters to a certain degree. I look for comfort first and foremost, but I also have to like the stuff I'm wearing. I want it to look reasonable, not for anyone else but myself, because it makes me feel good about myself. It doesn't have to be expensive stuff, there has to be a happy medium. Leggings, a nice sports bra and vest top will do me.
Yes, it sure does matter. I always go for a loose t-shirt, leggings, and rubber shoes whenever I go out to exercise. They are all comfortable to wear when you want sweat out.
The most important is to be comfortable. Anything else is just to show off to others.... I personally enjoy working out with sports leggings and a loose t-shirt and tennis shoes. Some people will tell me I should wear tighter shirts or sleeveless but I don't feel comfortable in those, so t-shirt it is, no matter what people say.
For me, it really doesn't matter. I look so awful when I'm exercising that, quite frankly, what I wear doesn't even make the slightest bit of difference to me. I will actually try to buy the cheapest exercise-wear that I can, because I know that more often than not I'm not even going to be seeing anyone that I know, so I might as well just wear whatever I'm comfortable in. There's no point at all in trying to spend money on exercise clothes, as nobody looks at you in them, and more often than not, you're not going to feel that attractive when you're exercising anyway.
It matters a bit if people will observe what you're wearing, so it pays to at least wear presentable workout clothes. I prefer to work out in knee-length shorts and loose t-shirt, so that when I sweat it's not as clingy as a fitted one.
I think it's important to feel as comfortable as possible while you're running. Personally, I wear only polyester clothes because they are light, easy to wash, they let your skin breathe, and they don't absorb sweat, making them very reliable. The bad thing is that most running shorts don't have a pocket so I think I'll buy an armband so I can keep my phone with me.