Radio 1 DJ Greg James said he has been surprising himself during his 'Gregathlon' - five triathlons in five days - for Sport Relief.
Get Inspired caught up with him during his Cardiff leg - and he went on to finish in Norwich on Friday.
If you're feeling inspired, get going like Greg! Walk, run, swim or cycle yourself proud at the Sport Relief Games from 18-20 March.
Take a look at our Triathlon guide to how to get started.