On Tuesday I had a good run - 4 miles of which the middle two (flat) miles were well within my target pace for Amsterdam - this warming up by walking the first mile seems to be hitting the spot :>). b-z commented when we were running on Sunday that it doesn't get easier as you get better - it hurts just as much, you just go quicker. I suppose that is what happened on Tuesday - I didn't feel those two miles were particularly 'good' I just suffered to better effect!
However today ....
MrBeanz's car needed to go for a service, I needed to run, but also to go to school for GCSE results. So the plan was take the car in and run home. I worked out how I could easily make the route nearly 4 miles, by incorporating one of my usual runs. But even after a mile or so of walking my right leg just did not want to know about running, and trying made my back ache, so I cut it short and just walked for 2.5 miles - but briskly (for me) 16 mm pace.
Ah well, you can't win them all.