Adults with arthritis ( N = 401 , aged 56.3 [ 10.7 ] years , 85.8 % women , 63.8 % white , 35.2 % African American , BMI of 33.0 [ 8.2 ] ) completed measures at a university research center and participated in a self-directed exercise intervention ( First Step to Active Health ( ) ) or nutrition control program ( Steps to Healthy Eating ) .