Bob Emmerson might have had both hips replaced in his life, but that hasn't stopped him finishing nearly 200 marathons and ultra-marathons in the last 35 years.
Now, Bob has set another personal best and has joined in at the weekly Racecourse five-kilometre community run 300 times since it kicked off five years ago.
Last Saturday (April 7), he crossed the line together with 83-year-old Diana Mary Green as she completed her 250th Park Run, where they were greeted with their own cakes by the Parkrun team.
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Bob, from Walgrave, said: "I insist that 300 is nothing special, it's just to prove my determination to keep going.
"The Parkrun has kept me going. I've met so many friends. Everybody at Parkrun is so friendly and lovely."
Since he took up running at 49, Bob has taken on 96 marathons and 96-marathons - races that can stretch up to 30, 40 and even 60 miles long.
He has had both hips replaced since he was 70 and has run the London Marathon 17 times in his life. Through careful log-keeping, he estimates he has run 110,000 miles in his life through races and marathons.
Bob said: "I just can't stop. It can give you such a good feeling and sets you up for the day.
"People say they can't run. Well, I say you can. You just run a bit, then walk for a bit when you get tired, then run for a bit. Then one day you can run the whole thing in one go."
Parkrun is held at the Racecourse every Saturday at 9am and draws hundreds of people a week to run a five-kilometre circuit together.
Run director Michelle Lewis said: "Bob is such an inspiration to everyone. He's up every Saturday to run with us and is such a gentleman to everyone. It just isn't the same when he isn't there."
Parkrun will celebrate its fifth birthday on May 5.