Curl up is also known as an abdominal crunch. This half-sit up exercise is used not only as a test for abdominal strength, but is also used as an exercise to tone your stomach. It offers many benefits for those who practice regularly. The Curl up test measures abdominal strength and endurance. It is important for back support and core stability.
One can do abdominal curl-ups as many times as he or she can. The proper technique for curl-ups ensures maximum benefits of this exercise and prevents losing too much energy. The exerciser should breathe in on the decline and breathe out on the upward crunch. In a crunch the lower back does not lift off the floor. Stretching the abs between the sets is also helpful, especially for beginners.
An approved crunch begins with you lying down, one knee bent, and hands positioned beneath your lower back for support. This is called McGill Curl up.