1. Start on your stomach and wedge the Swiss ball between your glutes and your calf
2. Bring your calf towards your butt and push into the ball firing your hamstring
3. Hold the position for about 30 seconds
Give yourself at least 2 minutes of recovery before performing another set. This move is a great way to get the hamstring to fire isometrically and can be a useful early rehab exercise for hamstring issues.