Most Effective Ab Exercise: Bicycle
Lie face up on your mat and place your hands behind your head, lightly supporting it with your fingers.
Bring the knees in to the chest and lift the shoulder blades off the floor without pulling on the neck.
Rotate to the left, bringing the right elbow towards the left knee as you straighten the other leg.
Switch sides, bringing the left elbow towards the right knee.
Continue alternating sides in a ‘pedaling’ motion for 1-3 sets of 12-16 reps.

 

 

The plank exercise is a great way to build endurance in both the abs and back, as well as the stabilizer muscles. This move is also great for building strength for pushups, an exercise that requires quite a bit of core strength.
How to:
Lie face down on mat resting on the forearms, palms flat on the floor.
Push off the floor, raising up onto toes and resting on the elbows.
Keep your back flat, in a straight line from head to heels.
Tilt your pelvis and contract your abdominals to prevent your rear end from sticking up in the air or sagging in the middle.
Hold for 20 to 60 seconds, lower and repeat for 3-5 reps.

 

The vertical leg crunch is another effective move for the rectus abdominis and the obliques. It’s similar to a regular crunch, but your legs are straight up, forcing you to use your abs to do all the work and adding intensity to the exercise.

How to:

Lie on the floor and extend the legs straight up with knees crossed.

Place your hands behind the head for support, but avoid pulling on the neck.
Contract the abs to lift the shoulder blades off the floor, as though reaching your chest towards your feet.
Keep the legs in a fixed position and imagine bringing your belly button towards your spine at the top of the movement.

Lower and repeat for 1-3 sets of 12-16 reps.