The primary cause of low back pain is instability of the lumbar spine, which is often the result of low back muscles that have been weakened by extended periods of sitting. One of the most effective ways to strengthen these muscles is to perform the reverse hyperextension exercise (which is illustrated in the following section). The VersaBack does a better job of supporting your body for this exercise than any other fitness product. The VersaBack"s elevated height also makes it very easy to get on or off of this device, even when you"re compromised by low back pain.