What up with this "core" stuff? When I ran (jogged) six miles a day 25 years ago you never heard of "core strength". Hey.....I even had a subscription to RunnersWorld and they never mentioned it. They just called it abdominal fitness. You see and hear "core" all the time now.
When did the term come about? Is it something that Jane Fonda came up with? I don't think it was Jack Lelaine.