1. Swing Ups

swingup1

Start lying faceup on the floor with the bottoms of your feet touching and your knees bent and dropped to the side in a “butterfly” position. Extend your arms overhead so they are resting on the floor.

swingup2

Swing your arms up and forward in an arc over and past your head, using the momentum to raise your shoulders and torso off the floor. Keeping your back straight and your elbows extended, touch your toes with your fingertips.

Keeping your elbows extended, reverse the motion as you lower your torso and shoulders back to the floor.

2. Plank

Start in a facedown position, propped up on your elbows, with your elbows aligned directly beneath your shoulders and your forearms resting on the floor. Your knees should be fully extended and your toes on the floor.

Squeeze your glutes, draw your belly button in toward your spine and raise your hips approximately one foot above the floor. Your body should be rigid and elevated from heels to shoulders. Hold the position as long as you can. Lower hips to the ground when you need to rest.

3. Twisters

twister1

Start lying faceup on the floor, holding your legs in the air perpendicular to the floor, your legs straight, and your arms extended outward like wings resting on the floor.

twister2

Keeping your shoulders and arms anchored to the floor and your legs together, swing your legs over to your left side. Touch your left foot to the floor to mark a complete repetition.

Keeping your shoulders and arms anchored to the floor and your legs together, bring your legs 180 degrees over to your right side. Touch your right foot to the floor to mark another repetition. Return your legs to the starting position.

4. Knees To Elbows

knees to elbow

Start lying face up on the floor with your arms extended overhead, hands and heels touching the floor.

kneestoelbow2

In one movement, draw your knees up toward your chest and your elbows down toward your hips, crunching upward with your torso so your buttocks and shoulders lift off the floor. Touch your elbows to your knees.

Original from:

http://www.mindbodygreen.com/0-17072/the-only-4-moves-you-need-for-a-strong-core.html

Extend your legs all the way back downward and your arms all the way back overhead. Touch your heels and the backs of your hands to the floor, returning to the starting position.