Core training has always been part of military PT and fitness testing. From crunches to sit-ups, flutter kicks, leg tucks and plank poses, the U.S. military uses many exercises to test core strength.

Core-stabilization training was derived from physical therapy in which injured patients needed to improve core strength after an accident or surgery. This specialized category of exercise made its way ...

Editor’s note: Dana Santas, known as the “Mobility Maker,” is a certified strength and conditioning specialist and mind-body coach in professional sports, and is the author of the book “Practical ...