Strengthening the hamstrings. Part2of3. The thrust & roll

Part1 of this series - the reverse aeroplane - stretches and strengthens the hamstrings with particular emphasis on working the muscle through a full range of possible motion.  Loads in the reverse aeroplane are not large but focused.  Part2 - the Swiss ball thrust & roll (T&R) - increases load but continues the theme of Glute co-involvement.
The swiss ball thrust & roll can be done with 2legs (an ideal warm-up even when you intend to advance) and 1leg.  The T&R can be viewed in the videos below.
The critical coaching points are these:

1. two discrete movements: thrust with soles against the ball, and the ball close to your bottom.  Don't move the ball during the thrust
2. with the hips held high, slowly roll the ball away from your body toward full knee extension.  Roll only as far as your high hip position permits - no hip drop is allowed   
3. roll the ball back to your bottom, and lower your hips onto the ground.  Repeat

video: 2leg thrust & roll

video: 1leg thrust & roll