Are you permitted to wear swim trunks to the gym?

You can wear trunks, ie. a swim suit with legs, not a speedo. As long as you have a modest appearance, the gym won’t mind.

But they aren’t designed for exercising and may be very uncomfortable. They aren’t designed for handling your sweat. And they may cause very painful chafing.

@zenvelo Update: I found some nylon pants that fit perfectly. I will change into them after I leave the gym on Friday March 22nd at 2:45pm… or I can wear the nylon pants to the gym and change to the jeans. I will ask my outreach worker seeing he will walk with my to the gym.

Dude.
Just make sure you are wearing something that respects community standards of modesty.

That depends on your area and specific gym.