Regular exercise can cut the likelihood of developing age-related macular degeneration by up to 70 per cent, a US study claims.
The authors, whose research appeared in the British Journal of Ophthalmology, based their findings on the number of cases of AMD among almost 4,000 US men and women in Wisconsin.
Participants were aged between 43 and 86 at the start of the Beaver Dam Eye Study in the late 1980s and were assessed through four examination phases at five-year intervals in order to determine the 15-year cumulative incidence of AMD.
On top of thorough eye examinations, the participants were questioned about their lifestyles and the amount of daily exercise they took, including climbing flights of stairs, daily walks and sessions of formal exercise.
One in four had an active lifestyle, and nearly one in four climbed more than six flights of stairs a day while approximately one in eight walked more than '12 blocks' a day.
After taking into account other factors, such as weight, blood fat levels and age, the researchers concluded that those leading active lifestyles were 70 per cent less likely to develop 'wet' AMD than those who led sedentary lifestyles. They also found that regular walkers were 30 per cent less likely to develop this variant.
'Other factors, such as diet, may explain the findings,' cautioned the authors. 'But physical activity is known to reduce systemic inflammation and irregularities in cells lining the arteries, both of which are thought to have a role in the condition,' they said.