I'd assume it was running up an actual hill.
Just running faster would be described as intervals/fartlek.
For 2x5 mins I'd assume you take a breather between the two sets, whatever you need to recover ready to do the second set, i.e. a few minutes.
This would be my understanding too.
@Greenbank started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
I'd assume it was running up an actual hill.
Just running faster would be described as intervals/fartlek.
For 2x5 mins I'd assume you take a breather between the two sets, whatever you need to recover ready to do the second set, i.e. a few minutes.