Plank

Exercise Overview

Plank is one of the best core exercises. You hold your body in a straight line over a period of time, the longer is the better. It sounds simple, but it is not that easy. The plank and all its variations will work your core muscles (the rectus abdominals and the obliques, as well as stabilizing deep core muscles) isometrically.
It is a foundation of all good bodyweight programs, and a great introduction to static, isometric work.
And like almost calisthenics exercises, it requires no equipment and can be performed just about anywhere (well, use your judgment).

Plank muscle worked

The progression

Choose one of the following variations as a starting point and hold the position for 30 seconds. Gradually build up to a hold of one minute over time. When you can do the exercise for one minute, move on to the next variation in the progression.

1. Kneeling plank. 

Performed on your knees, with thighs and spine in line.

2. Kneeling side plank. 

Bend your legs at the knee at a right angle and keep your thighs and torso in line. Your forearm, elbow, knee and lower leg are your points of contact with the ground.

3. Plank. 

With your weight resting on your toes and forearms, keep your core muscles tight and remember to breathe throughout the duration of the exercise.

4. Side plank. 

Can be performed with your upper arm at your side, or in the air. Aim for 30 seconds on each side, with a quick transition between the two.

5. Decline plank. 

Performed with feet elevated on a bench. Keep a straight back and remember to breathe throughout the exercise.

6. Leg lift plank. 

From the plank position, lift a leg straight behind you, parallel with the floor. Hold one side for up to 30 seconds; then change legs for the remaining 30s.

7. Arm and leg lift plank.

 From the plank position, lift a leg up and its opposite arm. Keep a horizontal back throughout the exercise. Hold one side for up to 30s; then switch arms and legs for the remaining 30s.

8. Wall plank. 

Performed with your feet flat against a wall. Prop yourself hard on your forearms and dig the soles of your feet hard into the wall.

Common mistakes

1. Collapsing the lower back.

The Fix: Instead of compromising the lower back by dipping the bum, engage the core by imagining your belly button pulling in toward the spine. This will help keep the torso flat, and in turn, the spine safe. If you want to get super technical, have a friend gently place a broomstick or yardstick on your back—the top of the stick should make contact with the head, and the bottom of the stick should rest between the buttocks. The stick should also make contact right between the shoulder blades for proper alignment.

2. Reaching the butt to the sky.

The Fix: Planks aren’t supposed to look like a downward dog. To really get the core working the way it should in the plank position, keep your back flat enough so your abs feel engaged from top (right below the sternum) to bottom (directly below the belt). Just don’t dip the tush too far toward the ground.

3. Letting the Head Drop

The Fix: While the focus may be on keeping the hips, butt, and back in the proper position, form isn’t only about the core and the lower body in this move. It’s important to think of the head and neck as an extension of your back. Keep your eyes on the floor, letting them rest about a foot in front of the hands, which will help keep the neck in a neutral position.

4. Forgetting to breathe.

The Fix: It’s human nature to hold your breath when in a strenuous position for a period of time. But denying yourself oxygen can bring on dizziness or nausea, which is unpleasant at best and dangerous at worst.