There are probably different ways of doing it with different apparatuses and different temperatures and all, but that also speaks to it drifting into junk, or at least unproven, science as well.

There's plenty of subjective wellness to talk about from people who do these things, anecdotes for days about feeling better after a session or two or whatever. But this really needs to be kept in context with just how many ineffective treatments can 'feel good' as well as how many aches and pains aren't actually as bad as people might think so they conflate natural healing with 'must have been that magic tube I sat in'.

For the most part, when it comes to pro athletes, it's important to keep in mind too that these guys basically have to at least try every single possible (legal) gimmick and novelty and they are essentially paid to do so as well. (Certainly if you were trying to sell WBC machines having a superstar athlete demo them would go a long way towards helping you accomplish that)