Moderate and Hard Physical Activity are Associated with Increased Total Energy Expenditure in Overweight and Obese Individuals with Knee Osteoarthritis

Abstract

Osteoarthritis (OA) is the leading cause of chronic disability in the elderly and the most common degenerative joint disorder in the United States. OA is characterized by cartilage degeneration leading to joint pain and tenderness, loss of mobility in joints, and inflammation. A major modifiable risk factor for the development of OA is obesity, where those with a body mass index (BMI) greater than 30 kg/m2 are 6.8 times more likely to develop knee OA compared to men and women of normal weight. OA is a progressive disease, where those who have mild‐to‐moderate OA may respond better to lifestyle modifications, such as physical activity or dietary interventions, than those who have severe OA. The objective of this study was to investigate the relationship between different levels of physical activity (light, moderate, hard, and very hard) and total energy expenditure in 94 overweight and obese men and women (average BMI = 32.77±6.34 kg/m2) aged 40–90 years with clinically diagnosed mild‐to‐moderate OA of the knee. A Seven‐Day Physical Activity Recall was used to assess overall pattern and level of physical activity and total energy expenditure (TEE) of participants. Out of all the levels of physical activity, moderate (r=0.580) and hard (r=.539) physical activity were shown to have a positive correlation with TEE, whereas light (r=−0.581) physical activity had a negative correlation with TEE. These findings implicate the potential use of hard and moderate physical activity as beneficial exercise intensities for increasing TEE for overweight and obese men and women with mild‐to‐moderate knee OA. Further studies are needed to fully understand the relationship between obesity and knee OA with regards to physical activity and the microenvironment of knee cartilage.