Incoming!

[Travs]

Definitely the core.

When i got into regular hard rep/track sessions, i found that my hamstrings were slightly lacking as well (or at least that's where i really felt it in the following days).

Another area i really noticed when i started doing longer AL's and ultra type fell races... upper arms and shoulders... probably a combination of carrying a rucksack for longer distances, and extended periods of time engaging my arms to provide balance. Considering the sporting background i come from, and the amount of gym time i put in, this was a surprise...