Physical activity may be what the doctor orders to help patients reduce their risk of developing glaucoma（青光眼） . According to a recently published scientific paper, higher levels of physical exercise appear to have a long-term beneficial impact on low ocular perfusion pressure (OPP), an important risk factor for glaucoma. Published in the journal Investigative Ophthalmology & Visual Science, this study examined the relationship between physical activity and current OPP in 5,650 men and women aged 48 to 90 who live in the U.K. and were part of initial cohort from 1993 -- 1997.

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 eye pressure -- medically termed intraocular pressure (IOP ) -- and systolic（收缩的） and diastolic（舒张的） 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.

"It appears that OPP is largely determined by cardiovascular（心血管的） fitness," said author Paul J. Foster, MD PhD, FRCS(Ed), of the University College London Institute of Ophthalmology（眼科学） . "We cannot comment on the cause, but there is certainly an association between a sedentary（久坐的） lifestyle and factors which increase glaucoma risk."

While there have been a large number of studies that have examined the effect of physical activity on intraocular pressure (IOP) and on blood pressure -- the two components of OPP -- this is the first time the relationship between physical activity and OPP has been investigated, according to the authors.

"Before now, the only modifiable risk factor for glaucoma was IOP, altered by medication, laser or surgery," said Foster. "We believe our study points toward a new way of reducing glaucoma risk, through maintaining an active lifestyle. This is a way that people can participate in altering their risk of glaucoma and many other serious health problems."