But one West Yorkshire man has put us all to shame, by managing to complete this feat six times - in just THREE DAYS!
Jake Hancock, 24, ran a total of 150 miles earlier this month to raise thousands of pounds for two charities close to his heart.
"I got inspiration from the Kevin Sinfield thing, where they are doing seven in seven," he said. "I just thought 'why not me?'.
"To start with, it was more of a challenge for me mentally and I thought if I could raise some money along the way then why not?
"But when you first say you're going to do it, you don't realise how big it will be!"
Jake used to play football and rugby but stopped due to various injuries, before becoming a keen runner in recent years.
Despite this, however, he admitted his experience of endurance running was limited.
"I had actually only run one marathon before doing this," he said. "It was about two weeks before. I have done a lot of shorter distances, but I have never run a Leeds or London Marathon or anything like that."
Jake overcame the odds and managed to run 52 miles a day, over three consecutive days this month. At the time of writing, he has raised nearly £4,000 for his two chosen causes, the Paediatric Intensive Care Unit at Leeds General Infirmary and the Nick Smith Foundation for Motor Neurone Disease.
"The amateur club i played for, Siddle, Nick Smith was the club captain. He was a young, fit 37-year-old when he was diagnosed. It was not long over a year before he died.
"I spent time with him on bank holidays and trips away - I knew him a bit and I am good mates with people who grew up with him.
"This foundation in his name aims to make an impact on peoples lives the same way as Nick did, they do this by supporting research into MND and providing help and support to those diagnosed."
He added that his second cause, the peadiatric intensive care unit at Leeds General Infirmary, was another that was personal to him, as his girlfriend works in the unit.
Electrician Jake, who lives in Halifax, said: "I saw what hard work it was with the stress of Covid. When we were all at home they had to go to work every day.
"I know first hand how tirelessly the staff work to provide such amazing care."
Jake said the money will be used to provide resources for the staff and the famillies of the children under their care, such as food vouchers, clean clothes, care packages and simple items for staff such as coffee machines, radios and food vouchers.
So how is he feeling after his gruelling feat?
He said: "I am still a bit sore, mainly in my feet and knees, but I am back at work now.
"To anyone wanting to do it, I would just say 'go for it' - if you've got something in your head and you think you can do it, why not? Put some time aside to train for it and you can have a go at whatever you set your mind out to do."
If you want to donate to Jake's run, visit https://www.justgiving.com/crowdfunding/jake-hancock.