More than 300 participants at this year's Yellow Ribbon Prison Run will sport a black armband with a red cross to identify them as trained first aiders, in a first for running events in the country.

The Ministry of Home Affairs (MHA) will be piloting the volunteer-based First Aider Marker initiative at the run next Sunday, in a bid to provide speedy medical help to runners in case of an emergency, such as a cardiac arrest.

The idea came about last year amid a spike in reports about people collapsing during runs, MHA assistant director of innovation Joel Ng told The Sunday Times.

"After what happened at the last Standard Chartered Marathon, we felt that was enough. There should be a simple way for the community to help save a life," said Mr Ng, 39, who leads a working group of innovators at the ministry.

Last December, 28-year-old Briton John Gibson collapsed after suffering a sudden cardiac arrest about two hours into the 21.1km run. His father, Mr John Robert Gibson, noted at a coroner's inquiry in May that there was a 10-minute delay before an ambulance arrived.

Although state coroner Marvin Bay found that the organisers complied fully with established plans and procedures, he called on them to "identify any areas for improvement, particularly in the area of expediting assistance" to those in need of medical attention.

Mr Ng said the initiative aims to encourage fellow runners who are on the ground to step up as first responders. "In a cardiac arrest, the first few minutes are crucial in ensuring the person's chances of survival," he added.

About 7,000 participants are expected at the Yellow Ribbon Prison Run.

The annual event will feature a 10km competitive run and a 5km fun walk that will end at the Changi Prison Complex.

Yellow Ribbon Project secretariat Koh Beng Hong said besides the volunteer first aiders, there will be three ambulances with paramedics along the route, as well as four roving paramedics on bicycles, four first-aid stations and a sports doctor at the run.

"However, at such events of mass participation, fellow runners provide the closest and quickest support," Ms Koh added.

Dr Henry Chua, 34, who works for healthcare provider Parkway Pantai, said runners face risks from physical and heat injuries, due to a lack of hydration as well as overexertion.

Mr Ng said apart from cases of cardiac arrest, the first aiders will also extend a helping hand to those who sustain such injuries.