They provide you with the equivalent of oversized scrub pants and an oversized t shirt. This is for the common area mind you. When you are in the mens area with the shower and hot tubs, you are buck naked. They may not allow clothes there.
Flapping in the wind lol
Don't need them
In the locker room/wet area you are naked, in the co-ed common area you are wearing the provided shorts & tee shirt, as for flopping around...the shorts are down to your knees so if something flops out then you need to train your Dragon.
Some wear undergarments, some don't...
You can choose to wear your tidy whities under the shorts... But flashing in the wind could be invigorating!!
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