One of the best ways to stay fit is by strengthening your core. It is not just enough to do sit ups and  perform ab crunches to tone your core. To build core strength you need to carry out exercises that work on a variety of muscles. Here are five best exercises that can help you strengthen your core without much effort.

Knee Fold Tuck 

Sit tall on the floor with your hands down and knees flexed, with a playground ball squeezed between the knees. Now extend arms in front of you and lift your knees up so that the shins are almost parallel to the floor. Keeping your upper body still, gradually pull the knees towards your shoulders, making sure the ball remains squeezed between them. Slowly bring the knees back to original position. Repeat 15 to 20 times for a set.

Climbing Rope

Sit on the floor with legs stretched straight and feet turned out in a V position. Contract the core muscles and roll your backbone into a C-curve. Now lift your arms and move them as if you are climbing a rope, twisting your body slightly with each reach. Do 40 reaches with both arms, 20 each.

Side Balance Crunch

Position yourself so that your left knee and left hand are on the floor and the right arm is straight up. Now extend your right leg so that your body forms a straight line. Now pull your right elbow towards the right knee and knee towards the torso and then straighten both the arm and the leg. Repeat 10 times for a set before switching sides.

Circle Plank

Plank position also helps strengthen core muscles. The longer you can hold the plank position the stronger your core will be. Begin in a plank position, the typical pushup position, with your forearms on the ground instead of hands. As you take the plank position, your abs should be tight. Now pull your right knee in and rotate it clockwise, then counterclockwise. As you circle the knee, keep the rest of the body stationary. Repeat five times for a set and then switch legs.

Sliding Pike

Sliding pike is best done on an uncarpeted floor. Again start in a plank position with your hands shoulder-width apart and a towel under your feet. With your legs fully stretched, gradually raise your hips and pull your legs towards your hands, until you get the pike position. Hold for one count before returning to the original position. Repeat 10 times.

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