One marathon is enough for some runners but Suffolk accountancy worker Karen Hamilton has completed 50 before her 50th birthday.
The mum-of-two, from Stowupland, ran the Dopey Challenge held at the famous Walt Disney World Resort in Florida to celebrate her incredible achievement in the New Year.
Now she is aiming to complete 100 marathons by the end of 2020 which means she'll need to complete 50 more by the end of December.
Surprisingly, she only took up the sport in 2016, after spotting an advert for a local parkrun.
"I was sat in Playworld in Ipswich with the kids," she recalled.
"I was reading a magazine and saw the advert and thought why not - I ended up doing five parkruns in five weeks."
It wasn't long before Karen took on more and after running 24 in the last year she has completed the milestone London Marathon, which she ran for Lizzie's Fund, a charity close to her own heart.
The special Florida trip was planned a year in advance in anticipation for the big milestone ahead of Karen's 50th on Tuesday January 28.
"It was the best marathon I've ever done," she admitted.
"I had to sit on my hands for the whole of December so I didn't sign up for another one.
"Although it wasn't my fastest time because I stopped every mile to pose for photos with Disney characters.
"I must have lost about an hour and a half from stopping to queue for five minutes to get photos, it was totally surreal running round and seeing these things, I was counting down the miles in between characters."
January 2020 was the hottest on record in Florida and humidity was strength sapping for runners taking on the four day challenge.
Each day the distance increased, starting with a 5K on Thursday January 9, 10K, half marathon and finally the full marathon on the Sunday.
With long distance running, speed is not necessary - Karen says she isn't particularly fast but just keeps on going and pushes herself.
She added: "I see running as a personal challenge, one of my friends calls me Forrest Gump.
"I don't really think of anything when I run, it's weird I get to the end and think what did I even think about for the last four hours."
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