Glaucoma is the second most common cause of blindness in the United States.  Paul J.  Foster, from University College London (United Kingdom), and colleagues examined the relationship between physical activity and low ocular perfusion pressure (OPP), an important risk factor for glaucoma. The team analyzed data collected on 5,650 men and women, ages 48 to 90 years, residing in the UK and who were initial enrollees in The EPIC-Norfolk Eye Study in 1993. Using a detailed self-administered health and lifestyle questionnaire, participants were assessed for combined physical activity at work and leisure. From 2006 to 2010, study participants were examined for intraocular pressure (IOP), as well as systolic and diastolic blood pressure measurements. The results showed that moderate physical exercise performed approximately 15 years previously is associated with a 25% reduced risk of low OPP.  Writing that: “Lower levels of physical activity were associated with lower [ocular perfusion pressure],” the researchers submit an association between a sedentary lifestyle and factors which increase glaucoma risk.