Well, when One is basically trapped in a box (studio apartment that One's hoarder friend lets One crash in) with narrow pathway between kitchen and bathroom, and One's friend is sleeping most of the day so One has to be quiet... It's a big challenge. If He would let Me have a key,,,
So I do a bit of yoga. That's about all I can do.
You may find free help from experienced people on the subject who can help him. Hoarding is a serious illness. Intervention may very likely be necessary.
He's 60, and won't discuss the issue. I would rather just try to get out than deal with His anger if I press it. He does not think He has a problem.