Starting Position: Begin kneeling on the right knee with left foot forward holding a medicine in both hands. Keep the ball close to your body. Engage your abdominal / core muscles to stiffen your torso and stabilize your spine. Your torso should vertical to the floor.
Bring the medicine ball toward your right hip, but do not rotate your torso. Your chest, hips and head should remain facing forward at all times throughout this exercise.
Slowly bring the medicine ball up and across your body above the left shoulder and slightly behind you. Do not rotate your torso. Keep your chest, hips and head facing forward. Keep the medicine ball relatively close to your body. Hold this end position briefly before returning to your starting position.
Repeat the movement in the opposite direction with the opposite leg forward.
Exercise Variation: To increase the intensity, repeat the same movement, but extend your arms at the elbow and maintain this arm position throughout the hay bailer movement. The longer lever this creates increases the loading on the spine, requiring the core muscles to work harder.
As much of your body weight is resting upon your knee, it is advisable to place a foam mat, pad or rolled up towel under that knee to reduce any discomfort.