Adding a medicine ball to the plank increases the demand on various muscles
for stabilization. Using a single leg on the medicine ball forces your core to
work even more. Finally, adding single leg abduction/adduction is yet another
progression to make the plank more difficult for the core as well as work your
inner and outer thigh muscles and flexibility.
This medicine ball abduction plank
is a great exercise to use in a core and abdominal workout. Another smart use
for this
exercise is to do it between other resistance training exercises in a circuit
training workout. The larger and harder the medicine ball is (in addition to the
hardness of the surface) the more difficult this exercise will be. In
addition to medicine
ball workouts, you can utilize the medicine ball as a substitute for
any elevated surface such as a Reebok step.