Lower back fitness is determined by using the CPAFLA protocol to measure physical activity participation, waist circumference, flexibility, and endurance of the abdominal and back extension muscles.  Back pain is one of the most common disabilities and ailments people suffer from.  It affects approximately 20% of the working population each year and is a major contributor to lost time from work.  The higher the level of a person’s physical activity, the less likely they are to suffer from back pain because of stronger core muscles on the spine.  Flexibility represents the range of motion that an individual’s back and abdominals can sustain.  The endurance of these back and abdominal extension muscles is evaluated by measuring the length of time muscles can support the body.  A Back Health assessment is important for people to undergo as it is indicative of their current level of back fitness and potential back pain.  A health professional can use this information to prescribe exercises that can prevent or reduce back pain for the individual.  Below shows an example of how back health is measured.  The back health score is composed of a weighted average of waist circumference, sit-and-reach, curl-ups, and back extensor endurance.