A Theoretical Perspective on Exercise Adherence and Osteoporosis using the Theory of Planned Behavior and the Social Cognitive Theory

Osteoporosis is a disease characterized by the loss of bone mineral content and density due to a number of factors, including physical inactivity. It is becoming a major health issue, with an osteoporotic fracture occurring every 3 seconds worldwide. Studies have shown that components of physical fitness have been better predictors of bone mineral density than age; however, adherence to exercise programs is poor, with 50% of those registered dropping out within the first 6 months. The Theory of Planned Behavior (TPB) is one of the most prominent theories for predicting health-related behaviors, especially exercise behaviors, but it does not include an explicit environmental factor and the Social Cognitive Theory (SCT) does. We propose that the environmental construct from the SCT could be used to augment the TPB, resulting in a better understanding of the barriers and facilitators to exercise in the osteoporosis population.