Side abdominal muscles (internal and external obliques)
You can make the exercise harder by using a ball. Lean on the ball sideways with your buttocks on the ball and perform the side crunch. You can make it easier by using wall as a support to balance the ball.
To make it harder you can place your hands behind your head with your elbows out or position your arms straight over your head. You can also make the exercise harder by holding a weight plate across your chest for added resistance. Another way to make the exercise harder is to hold a dumbbell with your arm closest to the floor, hanging the arm down with your elbow slightly bent and placing your other hand behind your head for support.
Do not rapidly raise and lower your upper body. Keep the movement slow and controlled
When performing the side crunch using an exercise ball, focus on maintaining proper form and balance. Do not bend your neck as you raise your upper body. You should keep your head, neck and back in a straight line during the entire exercise. To help keep the ball steady and maintain your balance, do not move your body forward or back.
At any point during the exercise, avoid quickly raising and lowering your upper body. As with other exercises, you should perform the side crunch in a slow, controlled manner to avoid injury and to get the full benefit of the exercise
If you have neck problems, take extra care when performing the side crunch. You should not perform this exercise if you are suffering from back problems.
Do not bend your neck. Keep your head, neck and back in a straight line.
Do not move your body forward or back.
Do not rapidly raise and lower your upper body. Keep the movement slow and controlled
