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 16-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 Polestriding/walking program combined with isometric strength training. BMI, body composition (Bod Pod, LMI Inc.), isometric leg strength (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 16 weeks.

Results:

Subjects increased walking speed (.14 +/-.13 m/s), distance covered in 6 minutes (49.7 +/- 42 m) and leg strength (13 +/- 23 lbs.) Modest changes were observed in body composition; body fat percent lost was 1.4 +/- 4%, pounds lost 3.4 +/- 9, and BMI remained unchanged. Physical function (WOMAC) improved by 18%.

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.