Because they're an unnatural device created by a need for puritan modesty and 'fashion'. They're also detrimental to your posture, and your tits. Think about always riding in a wheel chair, what kind of shape are your legs going to be in? Breast may not have muscle in them, the supporting tissues do.
Greek and Roman woman wore primitive bands during athletics. It wasn’t about modesty, it was about support and not having your tits bounce around. It was a tool. Ditto for guys and briefs, but tits can weigh a hell of a lot more.
Modesty is part of contemporary usage, but it ain’t all about modesty. Undergarments are functional tools as well. Humans make all sorts of tools to make their bodies get around more efficiently.
I have massive tits and I am physically active. I also have a physically demanding job. I think people (mostly men but also women with smaller breasts) don't realize how much they just straight up get in the way!
And I'm nearing 40. And have had a child! They get pendulous real quick and I have a feeling by the time I retire I'll be able to tuck them into my waistband! I am a liberated woman! I come from hippies! I even went a couple years completely without a bra! Strapping these fuckers out of the way has nothing to do with a fear they are sinful or might be seen and everything to do with not having the time to bat them out of the way every thirty seconds.
I also hate the pivot from "we need better boob operator equipment" to "Well akshyually if you didn't wear bras at all it wouldn't be a problem." Okay fucko you think you have all the answers about why breasts are saggy, how about addressing the problem?
Yeah I'm a man but I have a wife and quite a few friends with medium to large chest extensions and I do not envy them - the inconvenience looks like a right pain in the hole. I find running for a bus bad enough in the morning without having to worry about things getting out of control up there. Unless you're planning on being stationary a lot (basically not doing day to day activities) you're going to need support for those things.
My wife keeps trying to arrange a free bra fitting at M&S but it seems like that's a high demand service...
Lots of guys wake up everyday and wear briefs and boxer briefs over boxers or going commando because they like the support. Hell, Saxx underwear is huge right now, and their whole thing is about providing support. And that’s for some junk that can weigh a lot less than a pair of tits.
Jock straps are to hold a cup so you don't get your balls smashed while playing sports. You only wear one in sports that involve a lot of risk of that happening.
I switched to the boxer briefs with a little pouch in the front for your junk, and it is amazing! I've still got a few pairs of the older ones, but I don't wear them if I have the chance because the extra support is so much more comfortable!
So, you should probably just stop talking since you don't have any clue what you're talking about here.
The need for support varies a LOT with size. I never wear a bra in my own home, and I rip the underwires out of the ones I wear outside. My breasts sag, but that's normal at 60+. But I'm a C cup, so they're only protruding about 3 inches even when supported. And I only do low-impact workouts for other reasons. I wear bras to put my boobs in the parts of my clothes that are designed to have boobs in them, rather than falling out the armholes or something.
A large-breasted woman with three or four times the pounds of flesh hanging off her ribcage is not going to be comfortable slinging them around braless all day, especially when they get out of sync, as boobs are wont to do when you're moving around. Especially if she's running or jumping. Her bra has to work hard, and requires more engineering than mine. She and I have the same underlying muscles, tendons and bones, but her whole balance is under much more stress.
Meanwhile for an A cup woman a bra is probably mostly for fashion. She could have completely flabby musculature underneath and they'd still be perky.
If men had balls the size of boobs they would understand better how they can get in the way. And go 2 different ways! And it would probably be difficult to design comfortable underwear for them.
Bras were invented by women, for themselves, for their own comfort. Yes, SOME bras are unnatural and fashion-driven, and even those serve an occasional purpose. If you're a woman who doesn't ever wear a bra, great! Enjoy! Nobody should ever force anyone to wear a bra against their will. But if you choose to go braless, remember it's not necessary to disparage the women who make a different choice for their own reasons.
You're alluding to leg atrophy from wheel chair use, but could you go ahead and explain how you believe not wearing a bra would be less detrimental to your tits?
(I don't disagree where you say it's bad for your posture, and I'm not even sure I disagree with you saying it's bad for your tits, which is why I'm asking for a clearer explanation. Maybe I just don't understand what you mean by "detrimental")
Every day motion keeps the supporting pectoral muscles in better shape. Strenuous exercise, or large breasts, tend to tip things the other way, because the supportive tissues don't build up the way muscles do. Topless yoga is great, topless 100m dash, not so much.
Basically, since the bra is holding up the breasts, the body isn't putting as much into the ligaments and such that would normally do the job. Resulting in saggier breasts than would result if you didn't wear one as often.
I don't know how much formal research has been done on it, but that's the usual line of thought.