Baby Boomers started the running craze. I just couldn't get into it. When I was in my 40's, I was getting physical therapy for a foot injury not related to running. The therapist said they were starting to see a lot of boomers with hip and knee problems due to all the running. All of that pounding wreaks havoc on your joints. What he says is true. Boomers are having knee and hip replacements in mass, now. I don't have any aches and pains. I told my doctor I'm glad I sat on my ass all my life. lol!