I did my 2.5k run as part of the 10 is the Magic Number Week 1. I found it just as hard, if not harder than my hilly 5.5k on the weekend. Why is that? Was it my expectations? I thought it would be a breeze doing 2.5k on flat ground. It was a bit warm today, but still - I slept well, was hydrated, nothing out of the ordinary. Possibly still a little tired from the last run? Hoping Thursday's 5k won't be the same. Do other people experience this?