A GP from Dorchester is running the London Marathon for Alzheimer's Research UK in aid of his father, who was diagnosed with the condition seven years ago.
Simon Phillips, 38, works at The Cornwall Road Medical Practice and has been a prolific runner for several years.
He has completed the Edinburgh Marathon on three occasions and also took part in an ironman challenge in Dorset.
The ironman challenge is composed of three stages: a 2.4-mile swim, a 112-mile bicycle ride and, finally, a marathon run.
"I think you get into a mindset when you do something like that and you are just so committed for a while," said Simon.
"I do enjoy the running side of it, so it is nice to be able to concentrate on that for the marathon."
Simon's father Robert, 77, has begun to experience the symptoms of short-term memory loss associated with Alzheimer's and Simon said that the fact his father's condition has progressed will make this run "more poignant" for him.
There are more than 40,000 people under the age of 65 living with some form of dementia in the UK and Alzheimer's affects one in six people over the age of 80.
The fundraising target for Simon's marathon run is £2,000 and he has already been pledged more than half of that figure via donations to his Virgin Money Giving page and from visitors to his practice.
He said that the fundraising process had been a "family affair", with his mother helping to raise money to sponsor her son.
Training for the marathon is difficult for anybody, but Simon's hectic schedule as a GP has made things even harder.
He wakes up at 5.30 every morning to run, before taking on an 11-hour shift at his medical practice.
Despite the pressures on his time, Simon is unfazed by the enormity of the task in front of him.
"I am one of those people who needs a challenge," he said.
"If I have something to achieve, I will do it."
To donate money to Simon's fundraising efforts, visit virginmoneygiving.com/Simon.R.Phillips.
Are you running the London Marathon this year and want to share your story? Contact reporter Tom Beasley on 01305 830818 or email tom.beasley@dorsetecho.co.uk.
CONTACT ME:
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