Cross overs are a great exercise that help to strengthen the "core" muscles, which are composed of the abdominal, oblique and lower back muscles. Once the basic version of this exercise becomes too easy, be sure to lift your legs in order to increase the intensity. You'll be amazed at how this small change can make the exercise much more difficult.
About Cross Overs
As with all exercises, it is important to understand what muscles are targeted by the exercise, and why you want to strengthen these muscles. In the case of cross overs, the primary muscles that are targeted include the abdominal and oblique muscles, thereby making it a great choice for people who are interested in increasing their core stability. Your core stability helps you to maintain your balance while walking and performing a number of other daily activities that put your body in compromising positions.
Positioning Your Body for Cross Overs
Before performing any new exercise, you must learn how to position your body properly in order to achieve optimal results. To start, place a yoga or exercise mat on the ground, and lay down with your head, shoulders and back flat on the mat. Bend your knees, and allow the soles of your feet to also rest firmly on the ground. Bend your elbows, and bring your hands behind your head. Lace your fingers together, and use them to support the junction of your head and neck. Look up to the ceiling. Ideally, at this point your body should be in a straight line from your head to your hips.
Performing Cross Overs
Now that you are positioned properly, you can begin to perform the exercise. Start by taking a few deep breaths. As you exhale, use the muscles in your core to lift your shoulders and upper back off the ground, raising your chest toward the ceiling. As your chest raises, twist your core slightly, bringing your right elbow to your left knee. Inhale and lower your body back to the ground. Repeat the exercise, this time bringing your left elbow to your right knee. Be sure to perform at least 10 repetitons of the exercise before taking a short break. Do another 2 sets of 10 repetitions of the cross overs.
Increasing the Intensity of Cross Overs
As with any exercise, before increasing the intensity, it is important that you can master the basic form. Be sure that you can perform at least 3 sets of 15 repetitions of the basic cross over before attempting to increase the intensity. One great way to do this is by lifting your knees toward your elbows as you do the crunch. Doing this increases the resistance placed upon your stomach, therefore increasing the intensity of the exercise.