Since I only ever exercise at home where no one can see me, I've always worn truly awful clothes. The sports bras were nearly 10 years old, the clothes themselves were somewhere between 15 and 20 years old, and they had no redeeming qualities except that they're cotton and light and comfortable. They were horrible enough that if, while exercising, I had ever found myself in a situation where a fire alarm rang or I had to call an ambulance, I would have changed clothes into something that at least acknowledged that the 1980s had turned into the 1990s before saving my life. After reading about some emergency or another where people had to flee their apartment building with nothing but the clothes on their backs, I had actually worried about how humiliating it would be if I were stuck in my exercise clothes.
Just recently, on top of all those aesthetic problems, elastics started dying. I was crossing my arms under my breasts and tugging my pants up. So I finally decided to splurge on new exercise clothes.
I got Secrets From Your Sister to fit me with an exercise bra which doesn't let anything move (while still giving me a decent line) and is a very fun shade of purple. And I got a simple black and charcoal yoga outfit with lines that flatter my figure. Even though I shopped well and got everything at significant discounts, that's still about $100 spent on clothes for something I hate.
What I didn't expect is how good these clothes make me feel. I look like I'm aware that the 21st century has started! I look like I have a waist! And a figure! If I were interrupted without a chance to change clothes, I'd look like a perfectly competent, fashion-aware person who happens to have been interrupted while exercising. And, underneath it all, a fun purple bra!
Attractive exercise clothes don't help the tedium or sheer hatefulness of exercise, but they do help mitigate the indignity of it all. My morning feeling of "Blah, ugh, I have to go exercise!" is now accompanied by a tiny little glimmer of "But I get to wear my purple bra!" While it doesn't make the process pleasant, it does make it less unpleasant.
If, like me, you feel utterly disgusting and hideous while exercise, I do recommend getting something attractive and flattering to wear. It does help, more than I would have expected.