['To analyse the effects of 1 year of participation in a physical activity (PA) program linked to a health-care setting on physical fitness (PF) and health-related quality of life (HRQoL) and to determine the relationships between PA, PF and HRQoL in middle-aged and older adults.', 'In total, 3214 participants were recruited from a health-care setting. Sociodemographic data, HRQoL questionnaires and PF tests were applied by 37 employees at baseline and 1 year later. The participants were placed in an exercise group (EG) (n = 2614) and the remaining participants (n = 600) were placed in the control group (CG). EG performed the program 3 days/week for 50-60 minutes per session involving brisk walking with intermittent flexibility, strength and balance activities/exercises.CG participants were asked to continue with their usual activities. Data analysis included repeated measures analysis of variance, linear regression and contingency analysis.', 'EG showed significant mild-moderate improvement in all PF and HRQoL outcomes, especially in adjusted models. Changes in several PF variables were predictive of HRQoL changes. EG exhibited either improvements or no change in HRQoL dimensions. CG exhibited no change or declines in all dimensions.'] Are changes in HRQoL after 12 months of exercise linked to primary care associated with fitness effects in older adults?