Sunday’s Kingston Run Challenge was a soggy affair for all involved – not least for race volunteer Siobhan Eliot.

Siobhan spent more than five-and-a-half hours in the rain down by Embercourt roundabout in Thames Ditton guiding runners towards the Scilly Isles while holding up traffic until the coast was clear.

Not that the 50-year-old police officer minded one bit.

“Once you’re wet that’s it,” said Siobhan, from Portsmouth Road, Kingston. “I love doing it.

“I’m an athlete myself and I want to encourage other people to get involved in sport by promising I’ll be there clapping them on.”

Siobhan is no stranger to volunteering for events company Human Race, which organised Run Kingston – she’s been doing it for 25 years.

And when it comes to dealing with tricky customers – such as angry Sunday motorists being held up for a running event – Siobhan has learned one very simple truth. “If you smile at somebody they have to smile back,” she said.

“I call it my Sunday smile.

“I’ve been doing events in Kingston with Human Race for 25 years, and I’ve found the best and only way to deal with people is to smile. It’s irresistible.

“People on their way to church or their children’s activities, people who are in a rush – if you smile at somebody they will smile back.”

Human Race’s operations executive Adam Marcinowicz said: “Siobhan’s been there right from the start when the company was first set up and she still comes and helps out – whatever the weather.

“She always brings her enthusiasm and her joy – she’s a little bit crazy, but her uniqueness adds to the character of the event.”

Surrey Comet assistant editor David Lindsell, who ran eight miles in one hour and five minutes, said: “All of the volunteer marshalls on the route were so encouraging, clapping, cheering and giving the runners the will to get around the course.

"I’m delighted to see Siobhan nominated as an unsung hero.”

Do you know an unsung hero? Call the newsdesk on 020 8744 4723 or email jon.sharman@london.newsquest.co.uk.