Supine alternative to further establish robustness of the triple extension pattern, with focus on hamstring strength.

Start with your shoulders laying on a bench, a medball in line with your sternum, one leg in extension over a box and the other leg flat on the ground.

As the medball drops to your chest the foot on the ground engages in an explosive hip flexion. Press the ball back up.

Your extended leg will hit the box with its heel. As the pressing motion and hip flexion occur, the hamstrings of the extended leg have to generate an appropriate force to withstand the impact plus the perturbations created by the other extremities.

Maintain posture for a second to feel into the end-position.