Increased Mobility in Obese Elderly with Knee Osteoarthritis-A Home-Based Walking and Strength Program

Abstract

RATIONALE: Osteoarthritis (OA) is a leading chronic illness among older adults in the United States, and is second only to heart disease as a cause of inactivity for men 65 yr and older. Approximately 40% of individuals over 60 yr of age have OA of the knee, resulting in weakened muscles of the involved joints, immobility, and weight gain. objective: The purpose of this study was to determine whether overweight individuals with knee OA who completed a 24-week home-based walking and strength training exercise program would significantly increase walking distance, walking speed and quadriceps strength, and decrease body fatness and body weight. METHODS: Fifty-six sedentary subjects (50 men/ 6 women), mean age of 68 ± 8 years, with a diagnosis of knee OA by radiographic changes of Kellgren-Lawrence grade 2–4, and Body Mass Index (BMI) greater than 27 (34 ±6) participated in a balanced, home-based Polestriding/walking program combined with isometric/isotonic strength training. BMI, body composition using a dual-chamber plethysmograph, isometric leg strength using a cable tensiometer (index leg), 6-minute walk speed (m/sec) and distance (m), and perceived physical function via the Western Ontario and McMaster University (WOMAC) were measured at baseline and 24 weeks. RESULTS: Subjects increased walking speed (1.23 ± .29 vs. 1.39 ± .33 m/s, p < 0.005), distance covered in 6 minutes (444 ± 107 vs. 500 ± 119 m, p < 0.005) and leg strength (90.8 ± 32.5 vs. 106.4 ± 30.0 lbs, p < 0.005). Modest changes were observed in body composition; body fat percent was reduced (39 ± 8 vs. 37 ± 8%, p < 0.05), pounds were lost (227 ± 43 vs. 222 ± 42 lbs, p <0.001), and BMI decreased (34 ± 6 vs. 33 ± 5 kg/m2, p <0.009). Significant improvements occurred in all domains of the WOMAC score (p <0.001). CONCLUSIONS: Combined walking and resistance training exercise increases walking speed, walking distance, quadriceps strength, and perceived physical function and reduces body fatness and weight in the overweight elderly with knee OA.