You lower the bar to a soft piece of
foam where you pause without allowing
the bar to sink
and then press the bar back up.
Because you are
lowering to a soft surface as opposed
to boards, you
are required to press the bar up from
a static hold.
Pressing from a static hold makes the
exercise more
difficult than regular board presses for
many people,
and is another way to target the muscles
used at that
particular board height. Boards
can be added or
removed from under the foam to adjust
the height you
wish to train at. The foam can also
be used when
training tricep close grips.