This simple move is becoming a must-have for runners and strength athletes alike.

Your core is so much more than just abs—it’s the powerhouse that supports posture, balance, and everyday movement.

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.

Balance board workouts are a training method involving a series of standing and weight-bearing exercises completed on an unstable surface. They aim to train the muscles around the ankle and improve ...