I've been off the bike for the past week due to left knee pain. Judging by where the pain is located I suspected it was caused by not having my new bike properly fitted and by too many large hills during my 21 mile commute to work everyday.
I had my new bike properly fitted and the guy that did the fitting, who also happens to be an exercise physiologist, confirmed my suspicions. He said my seat was too low and I need to spin and not hammer up hills. I know, I need to spin but just can't help myself when going down a large hill, I love the speed and try to see how high I can get my mph to. Here's my question- in order to maintain cv fitness while I'm off the bike is it okay to run since running uses different muscles than cycling? I hate being in-active but don't want to do more damage to my knee which would mean even more time away from cycling.