Background: Physical activity and cardiovascular fitness are beneficial for HIV-infected individuals; however effects over a one year period are unknown. This study aimed to document habitual physical activity and cardiovascular fitness over a 12 month period in stable, HAART-treated individuals with HIV, explore relationships to body composition, body image and cardiovascular disease (CVD) risk and evaluate physical activity determinants. Methods: Eighty adults participated. Physical activity was reported using the International Physical Activity Questionnaire and cardiovascular fitness assessed using the Kasch Pulse Recovery Test. Results: 19-37% participants reported suboptimal physical activity levels at each study visit, while physical activity and cardiovascular fitness were largely stable over the study period. Higher cardiovascular fitness was associated with better body composition and this association persisted over time (p<0.03 for all). Greater total energy expenditure was associated with improved body image (r=-0.325, p=0.027) but not CVD risk. Being in a permanent relationship was independently associated with higher levels of physical activity. Conclusions: This study found benefits for both physical activity and cardiovascular fitness performed over a one year period for chronic HIV-infection. Future endeavours, including larger cohorts and longer follow up are needed to further explore factors that influence physical activity and cardiovascular fitness in HIV.