Core Workouts for Runners This means more than just having strong abdominal muscles. It extends to your lower back and gluteal muscles, specifically your gluteus minimus. The core is comprised of the rectus abdominis (the six-pack muscles), the transverse abdominal muscles (deep abs), the obliques (side abs), erector spinae (lower back muscles) and the gluteal muscles (your butt). Strong erector spinae muscles help give ...
March 10, 2014 - U.S.News & World Report LP via Yahoo! News