Yasmin Forrester, Jamie Prys-Owen and Steve Cowling will be setting off from the Greenwich start line on Sunday, April 23, in aid of Whitechapel-based homeless charity Crisis.
They will be joining thousands of other runners for the 26-mile route passing through Canary Wharf on their way to the finish.
They had to battle it out with colleagues for a chance to compete and found out in the first week back after Christmas they were the chosen three.
They now have nine weeks left to train and raise £2,000 in donations each.
Mum-of-two Yasmin said: “If I’d known before Christmas I would have laid off the mincepies.
“I’ve always used running to lose weight for special events such as my wedding but haven’t done much exercise since I had my kids.
“But I have always wanted to do the marathon and am hoping to lose some weight during training.”
The lettings manager, based in Greenwich, has so far raised £900 for Crisis and said: “I have seen the creme de la creme of properties in Greenwich, families moving into six-bedroom homes with saunas and pools.
“And then you have these people on the streets who have absolutely nothing.
“So this is my way of giving back.
“Everyone at work’s has been really supportive and every time I reach for a biscuit I have 20 people telling me no.”
In contrast client services consultant and experienced runner Steve has more than doubled his calorie intake to 4,500 a day.
“I use to skip breakfast and sometimes lunch if I was having a busy day at the office but now I have to make sure I’m eating,” he said.
His runs already stretch to 27k (16miles) and the 27-year-old who works at the JLL office in Westferry Circus and Nine Elms said: “It might sound a lot but when I get to the end I know I will still have to do another 15k on the day.
“But I don’t want to overdo it in training and end up burning myself out.”
He has raised £1,100 so far and said: “Crisis is a charity that can really make a difference. Homlessness is such a preventable problem in so many cases.
“Going out for a run in these freezing temperatures is a stark reminder of why you are doing it as while I only go for a to hour jog in the cold some people have to sleep and live in it all the time. That is my motivation.”
Surveyor Jamie Prys-Owen, 23, based in the firm’s Warwick Street office said: “Crisis is a charity I feel strongly about so I jumped at the chance to support them.”
His training had a setback when he was diagnosed with shin splints and had to stop running for three weeks but he is determined to get back on track and hit his donations target, with £1,000 raised so far.
“I just have to stay motivated as the end goal is in sight now,” he said.
UK community manager at JLL Gemma Piggott said "At JLL we place a strong emphasis on supporting charities.
"We're delighted to be able to support Crisis through our participation in the London marathon."
Support the runners on their fundraising pages
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