Apparently my gluteus medius are quite weak, which is why I am starting to have pain while walking in one hip, and I guess it doesn't help that the piriformis muscles are tight (both sides). Thankfully neither bike nor spinning bike causes pain - and between my PT and trainer we will be able to reverse this.
What I don't understand is how this snuck up on me - it isn't like I haven't been very active for the last 1.5 years and have been doing a lot of walking and strength training :confused: :( Oh well, I guess that just means I am no longer 30, or even 49...

