I'm trying to help a relative get fitter and lose weight. He would like to do something at home as he is a bit of a recluse and would hate classes. He was considering an exercise bike. I know nothing about these things, but was wondering if anyone had any advice? He is v overweight and I'm not sure if there are weight limits on bikes? He also has knee problems which are being exacerbated by his weight. His home doesn't have a lot of room so it would have to be quite compact.
Any words of wisdom?