A TOTAL of 117 elderly folk who have cataract will get free surgery to restore their vision by the end of the year, thanks to a group of running enthusiasts.

The volunteers took part in Mount Elizabeth Hospital's first Run for Cover Challenge, which saw teams take turns to run on treadmills for 24 hours non-stop.

Every 30km clocked raised enough money for one operation. The cataract removal procedure can cost up to $5,000 per surgery.

The marathon session started at 2pm on Saturday, and a day later, more than 280 participants - including 80 who were competing against one another - had run over 3,500km in total at the event, which was held at Ngee Ann City Civic Plaza.

Cataract is a common condition in which the lens of the eye becomes cloudy with age, causing the vision to become blurred.

The winning team, a group of National University of Singapore students and graduates, achieved the longest distance - nearly 319km.

The men each won $5,000 worth of free health-care insurance from the hospital that will cover them for up to $700,000 a year for 10 years.

Taxi driver Daniel Chia, whose team came in second with about 304km, said the humidity had made the effort a form of "mental torture".

"It's quite different from running in the open, where you get wind and scenery," said the 55-year-old, who is part of a running club that meets every Sunday at MacRitchie Reservoir.

He added: "Our target was to reach 300km - we're very happy that we exceeded it.

"We like running, and it's for charity, so why not?"

AMELIA TENG