Doing week 4 again! I did the first 2 runs, then had a week off due to a trip up home to visit the family. The last run was awful as I’d been sat in a workshop for 4.5 hours without moving and my legs were super heavy and calves cramped up.
Today I stuck them up in the air for 30mins when I got home from work and foam rollered them as well till they were all relaxed and floppy. That helped!
I also tried visualising my run from a route I used to do last summer (was on my treadmill, but it did take my mind off clock watching a little bit).