When crime analyst Tessa Denham-Cookes took up running last year she could barely make it to the end of her street without getting out of breath.
Just a few months later, the 25-year-old from Watford is gearing up for the London Marathon.
She said: “I saw the marathon last year and remember thinking to myself ‘it would be nice to one day to say I’ve done it.’
“Then at the end of summer I decided I wanted to keep fit.
“So I started running and it just went from there.”
Tessa plans to compete in the event to raise money for Cardiac Risk in the Young (CRY).
She said: “I knew I wanted to support a small UK charity in preference to a larger international one, so I was really happy when I won a spot running with CRY.”
Tessa is now training in the gym several times a week and completing a long run each weekend.
She said: “I’ve never felt particularly fit. I’ve never been really sporty, but I can really see the difference.”
Her family, and workmates at her base in Collindale have encouraged and supported her and have helped Tessa with sponsorship.
She currently needs to raise £1,250.
Anyone wishing to sponsor Tessa, can log onto www.just-giving.com/TessaD-C