Lie on your back and lift your leg up towards your chest, holding your calf as demonstrated, until you
feel the stretch in your hamstring. It is important that the leg is straight, but that
you don't lock you knee.
This stretch forms a similar purpose to the hamstring stretch detailed with the
warm up stretches. Some say that it is more effective as there is the ability to
put as much stretch into the muscle as you like and also none of the other muscles in
the area are tensed due the weight bearing during the exercise.