A | Position yourself on a large fitness ball to support your upper back. Align shoulders with hips, keep feet hip-width apart, knees bent at 9O degrees, and abs and glutes tight. Holding a weighted medicine ball or the ends of an 8-pound weight, extend both arms directly overhead, palms facing each other.
B | Keeping upper arms and elbows stationary, bend arms to lower the weight to the crown of your head. Slowly press weight back up, straightening arms. Do 2 to 3 sets of 12 to 15 reps.