Meier NF, et al. - In this prospective observational study, the researchers analyzed the associations of physical activity and cardiorespiratory fitness (hereafter fitness) with incident glaucoma. By self-reported leisure-time activities, physical activity was measured. By maximal treadmill test, fitness was measured. Study participants were 9519 men and women between the ages of 40 and 81 years old (mean age 50) who were recruited in the Aerobics Center Longitudinal Study. A joint analysis of physical activity and fitness demonstrated that meeting physical activity guidelines and being in the high fitness category was correlated with the lowest risk for developing glaucoma. It was concluded that meeting physical activity guidelines or being fit decreases the risk of developing glaucoma.