Why My Knee is Injured

My old home and neighborhood really gave my knee a work-out. There were stairs all over the place plus the yard was steeply graded. If I went for a walk or run around the block, I negotiated steep hills. No wonder I'm injured.

Marathon running only occupied the last three and a half years - with months off for an inflamed tendon, broken fifth metatarsal, and torn calf muscle. 

What does this mean? I blame my house and neighborhood. No lawsuits, but I'm starting a whispering campaign that they're intolerant of knees. Well, mine, anyway.