I know people say if you want to get better at karate, do more karate, but a) it's just not possible for me at the moment due to time and money and b) I think cross-training is better for you.
So... do people have any suggestions for cross-training? I own a punchbag and a bike and I get free gym and swimming. I've already noticed that the leg extension machine at the gym (sit with your legs bent, weights on your shins, and straighten your legs) works the same muscles as kibadachi. Quadriceps, I guess. I've also noticed that general fitness is an issue, and that I've got better since I've taken up running, in that my stamina for kumite has improved. I remember reading somewhere that cycling is good for building up leg strength for kicks. Do people have any other suggestions?
Another thing is that most of the long-term Shotokan karateka I know have knee issues. Does anybody know of any particular knee-strengthening exercises that could help prevent these? I already wear knee supports (elasticated bandages) when training or running, and I don't run on concrete.
Thanks for any help.
(Cross-posted to karate_women and karate_do)