| Dec 19, 2014
By Heather K. Vincent, Ph.D., FACSM
Physical activity is recommended to obese individuals by their doctors for weight loss and overall joint heath. Activities that increase caloric expenditure are helpful for reducing weight and offloading the joints of the body. However, obese individuals commonly experience low back or knee pain during exercise, leading them to avoid exercise. Avoidance behavior initiates a cycle of continued weight gain, worsened joint pain, pain catastrophizing, fear of movement (termed kinesiophobia) and disability.
The published literature has shown that people with chronic low back pain demonstrate fear avoidance behaviors and kinesiophobia. Separate research teams have identified different pain-related issues that contribute to exercise avoidance. First, pain catastrophizing triggers the negative pathway leading to physical disability. Second, obese and older populations have high prevalence of joint pain complaints that contribute to avoidance of physical activity. Third, obese individuals are more likely to catastrophize and ruminate about their pain issues than non-obese individuals. We are in the infancy of understanding the relationships between different exercise programs and the effectiveness on reducing fear behaviors, kinesiophobia and catastrophizing in the obese, older population with back pain. This is problematic, because clinicians do not yet have the information necessary to prescribe the appropriate exercise type or dosage needed to combat pain catastrophizing and kinesiophobia in this growing demographic. Evidence of exercise methods that can help clinicians empower patients to reduce pain, improve exercise tolerance, and achieve better musculoskeletal health is becoming increasingly important.
We recently published a series of papers showing that lower lumbar muscle strength was related to higher pain scores during activities such as walking and stair climbing in obese older adults with chronic low back pain. Kinesiophobia predicted perceived disability. We also identified a direct positive relationship between muscle strength and walking endurance. Our most recent study, published in MSSE, was a randomized, controlled single blind trial. The goal was to determine the efficacy of two different types of resistance exercise programs (total body exercise vs. lumbar extension only) compared to a non-exercise control condition on measures of pain symptoms, kinesiophobia, fear avoidance beliefs and catastrophizing and mobility. Walking endurance improved, especially when the lumbar strength gain was greater than 20 percent from baseline. We showed that even with no weight loss, total body resistance exercise reduces pain catastrophizing by as much as 64 percent. Total body exercise also reduced perception of disability due to pain and pain during physical activities more than lumbar extension.
In our view, these results indicate that resistance exercise with a lumbar strengthening component can be used to counteract the psychological steps that initiate avoidance behaviors and physical disability in this population. Reducing pain catastrophizing is an appropriate treatment target because the measure is related to reductions in ambulatory pain severity and perceived disability. Decreasing pain catastrophizing levels may help obese older adults with back pain re-assess the harmfulness of the pain and develop confidence in performing physical activities. We believe that regular participation in resistance exercise should be encouraged to help these patients positively change their personal experience with exercise to achieve high quality mobility (low pain or pain-free movement).
Viewpoints presented in Active Voice commentaries reflect opinions of the authors and do not necessarily reflect positions or policies of ACSM.
Dr. Heather Vincent is a research faculty member in the Department of Orthopaedics and Rehabilitation at the University of Florida (UF) College of Medicine in Gainesville, Fla. She is the director of the Human Dynamics Research Laboratories and UF Sports Performance Center. Her research is focused on developing appropriate exercise-based interventions for obesity to improve the physiological, mechanical and psychological disease risk factors and attenuate musculoskeletal disease progression. She is currently serving on the ACSM Consumer Information Committee.
This commentary presents Dr. Vincent’s views related to a research article she and her colleagues had published in the September 2014 issue of Medicine & Science in Sports & Exercise® (MSSE).