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.

Your core is so much more than a six-pack—it’s the powerhouse that supports your every move, from lifting groceries to crushing a workout. Training it properly means going beyond crunches and mixing ...

This mini core workout has helped me run regularly ...