Danielle Edgington-Gibson, who owns So Hair, Nails and Beauty, on Parsons Street, will be running the 26 miles in aid of Children with Cancer UK.
The 31-year-old mother-of-one and self-described non sporty person said she couldn’t believe she would be taking part in the event.
She said: “I can’t believe I am doing it. I have already raised just over £3,500 and I am really pleased. The donations have come from my clients, friends and family.
“My son, Bruno, has a friend who has leukaemia and I chose the Children with Cancer charity for him. He’s lovely and is fighting the good fight. Cancer seems to be everywhere at the moment.
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“I am not a runner so I started training at the end of last year. I’ve gone from couch to marathon!
“I’m looking forward to getting my Sundays back.”
She added she was running three to four times a week and had been going to the Witness the Fitness gym for cross training. She also plans to keep up the running after the marathon – but over shorter distances.
“I chose the London Marathon because people talk about the atmosphere there.
“Apparently it’s amazing and pulls in the biggest crowds. I have always loved London. I have wanted to get fit.
“I work so hard and I wanted to start focusing on me and raise money for charity.”
She has also received support from her husband, Paul Gibson.
“He’s been out twice with me. He’s not a runner either so I’ve been going on my own.”
She added 15 of her friends would be coming down to support her on the day and she had provided T-shirts for them.
To sponsor Mrs Edgington-Gibson, visit her fundraising page at www.virginmoneygiving.com/danielleedgingtongibson.