Decline oblique crunches will help to tone and strengthen your External Oblique muscles. To do this exercise you will require a decline bench which are common in all gyms. With your feet on the top of the bench, lay back and then slightly raise your upper body. For the initial exercise rep place your left hand on your left thigh and your right hand towards the back of your head. Lifting your upper body, turn your torso to the left until your right elbow touches your left knee. When you reach the knee position pause slightly and then return to the starting position.
Once you have completed a number of decline oblique crunch repetitions then place your right hand on your right knee and your left hand behind the back of your head. You will then twist your torso from the left to the right until your left elbow touches your right knee. The external oblique muscles, situated on either side of your abdominals, will be stretched and exercised thoroughly with decline oblique crunches.