The plank is a handstand and balance pose that strengthens the abdominal and lower-back muscles as well as the shoulders and upper back. Variations of the plank provide different levels of challenge and work diverse muscle groups. For example, the high and low planks engage the rectus abdominus and lower-back muscles, while the side plank focuses more on the obliques. The reverse plank focuses more on the lower back.
Lie face down with your forearms on the floor and your elbows directly beneath your shoulders. Keep your feet flexed with the bottoms of your toes on the floor.
Clasp your hands in front of your face, so your forearms make an inverted “V.”
Rise up on your toes so that only your forearms and toes touch the floor -- your body should hover a few inches off the floor in a straight line from shoulders to feet.
Draw your navel toward your spine and tighten your buttocks. Look at the floor to keep your head in neutral position and breathe normally.