With the body well extended lift the right foot, knee straight, as
far backward and upward as possible. Then release, and lift the
left foot in the same way.
This exercise should be used alternately and given a good deal of
activity. The heels may be extended or stretched downward as they are
lifted. This will give greater extension to the muscles at the back of
the leg.
This exercise causes extension of certain muscles which are kept short
when sitting. It is also beneficial for the back.