John Eales only started running to lose a bit of weight - but he quickly became addicted.
In less than a year he had jumped from a 5km jog to his first marathon, and after that he just didn't stop.
John told me how he would run "mile after mile" on the way to joining the exclusive 100 marathon club.
We talk about what it's like to run seven marathons in as many days, and how he may have to swap his trainers for cycling shorts in the future.
If you like this episode please consider donating to help us keep going: https://www.buymeacoffee.com/stepforward