What do you wear. I mean its an honest question. You can wear whatever you want, depending on what activities you do and what capacity you need to function. Honestly, nothing makes me feel better then walking into the gym with a tank top, with a sweater over it. Underneath I have sweatpants on, which i may double a layer with either compression pants or a pair of gym shorts.
I like to walk on the treadmill and get warmed up, then get my first few reps in with all my fall gear on. When the muscle is alot warmer, its easier to provide nutrients to the muscle. So, you end up getting a better lift. Then you take the sweater off and have a great look body because now your muscles are full and pumped with blood.
You can also wear sweat suits, but those really are just for cutting water weight and that is very temporary, however, keeping your body cool does cost some calories. I have not personally used them but some people love it. I will say that the ab saunas definitely don’t work, and that isolated sweating doesn’t burn away fat. Hell, not even isolated movements like crunches burn away fat. Calories are diversely burned through out the body.
So when it comes to what you wear. It really does not matter so long as you are comfortable and capable of doing the work. Now, I prefer to workout in adidas. There dri fit shirts work great and fit me great as an Xl. They also only cost about 12 bucks a shirt and I can usually find some nice sweats at marshalls for about 10-14$. Then nordstroms rack for shoes. Unless you are an intermediate powerlifter, or an avid runner, simple running shoes will work. You can even get casual workout shoes for about 40$ at marshalls. T
On these clothes I would never spend more then 120 dollars on, and I would have about a weeks worth of workout clothes and honestly by the time the year changes, you will probably want to throw those out along with some old boxer briefs or compression shorts.
In terms of underwear, either of these two styles of underwear work, its just up to you to decide does this feel right. Now, if you find yourself in yoga, or doing crunches on the ground alot in the summer, the boxer briefs may allow for a sneak preview which can easily be prevented with compression shorts.
Last are the shoes. If you run, buy running shoes and spend as much as you want. Or buy weight training shoes, those too can be expensive. As for me, I picked up a 40$ pair of Doctor Scholls athletic shoes and so far they have done the trick. You really do not need anything special, but if you love to run I definitely recommend getting the right shoe.
After spending so much time in the weight room with high school football players I know that you can lift whatever you want in converse. It just depends on how you want to look and feel, and to be honest, I think buying comfortable clothes that make you feel good about your body image is motivating. Especially if you get to throw them out at the end of spring because you are a totally different size.