I have definitely noticed lack of strength, especially six months in or so...what was once 20 pounds now like fifty-but the only muscle soreness I have ever gotten was during those times, like carrying milk, dog food bags in to the fur baby, etc etc. I do notice a little flab where arm muscles once were a bit more defined...but not much atrophy thay asside upper body strength wise other then forearms got tad more feminine as well as hands.