Ms Duff started training after her daughter suggested she “give it a go” and went into her first race “just trying to survive it”.
“It’s a very gruelling test and when I completed it I realised I could do it better if I refined some of my training and it built from there,” the double world Hyrox champion told BBC Radio Cambridgeshire.
“Even going for a walk, swim or bike – just doing something will add years to your life.”
The word Hyrox itself does not actually mean anything but it all started back in 2017 as a race.
Christian Toetzke, alongside Olympic champion hockey player Moritz Fürste, set up the first race in their home country of Germany.
At the 2023 World Championships in Manchester, Ms Duff secured the top rank, external in her age group, placing her in the top 9% of 11 athletes in the 65 to 69 category.
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