Lava shorts for injury rehab swimming??

I think Lava shorts would do the trick. My BIL hates the pull buoy so he uses the shorts instead. He says they are just as buoyant as a buoy.

Went ahead and ordered them. Hope I didn't screw up with sizing. Looks like it is unisex...The chart just gave hip size and it showed I needed Large??! I guess guys have smaller butts in general but--I'm an American size 2 or 4 for regular clothes, and have never worn "Large" before anywhere but maybe Vietnam! I have visions of the waist completely falling off and thighs flapping everywhere, but maybe they fit more like a wetsuit (really snug)?

I would think lava shorts would help... or heck even if you had an old wetsuit that you don't care about. Throw it on and swim in the pool.
Find a cheap used one on ebay.

I did order Lava shorts, tried them at the pool yesterday, but the sizing is really, really off! The size chart said Large based on hip size (first time I have EVER been recommended to order a Large in anything outside of Asia) but they were HUGE. Just wrote Xterra and gave them a few other parameters (waist, thighs, height, gender) and now they recommend a small. Don't think unisex sizing works too well! Might try the Small if I can get a full refund.

I do have a sleeveless shorty wetsuit (meant for OWS) but don't particularly want to trash it in a pool as I sometimes race in it when water temps are borderline wetsuit legal, and also use it for open-water swims in late summer (local lakes are still cool enough, and I'm cold-blooded enough, to want it then). Might end up using it instead though if I can't get the Lava shorts to work out.