Middle of the month

In the middle of each month, along with a few friends, I try to run for 1 hour on the track near my home. Up until now I have been doing this at 9 am on a Sunday morning, but since the weather has become much warmer we are now starting at 8am. Yesterday I was in Zagreb with some friends who swam in an open water 5km race while I ran 5km. I really enjoy a nice easy run with friends on a track, though I have noticed that for the last week my right Achilles has been a little sore.