The plank (also called a front hold,
hover, or abdominal bridge)
is an isometric core strength exercise that involves maintaining
a difficult position for extended periods of time
The most common plank is the front plank
which is held in a push-up position with the body's weight borne
on forearms, elbows, and toes
Many variations exist such as the side plank and the reverse plank
The plank is commonly practiced in pilates and yoga, and by those
training for boxing and other sports
The plank strengthens the abdominals, back, and shoulders
Muscles involved
in the front plank include
primary muscles
erector spinae and rectus abdominis (abs), and transverse abdominus secondary muscles
trapezius (traps) and rhomboids and rotator cuff and the anterior,
medial, and posterior deltoid muscles (delts)
and pectorals (pecs) and serratus anterior and gluteus maximus
(glutes) and quadriceps (quads), and gastrocnemius
Muscles involved in
the side plank include
primary muscles
transverse abdominus and gluteus medius and gluteus minimus muscles
(abductors)
and the adductor muscles of the hip and the external and internal
obliques secondary muscles
gluteus maximus (glutes) and quadriceps (quads) and hamstrings