If ever your training plan calls for two fast miles, do not try to run them as part of Queen Elizabeth parkrun the day after a 20 mile run.
If ever your training plan calls for twenty minutes of all out effort, then I can’t think of a better place to attempt it than as part of Queen Elizabeth parkrun the day after a 20 mile run. Especially if you enlist the help of Kiernan to set you up with a pacer to use if it turns out that you are a running goddess (I wasn’t) and a fall back pacer to use if you turn out to be a bit of a wimp (I was).
Oh, and memo to self. Do *not* warm up with a run through a grassy field. Grassy fields are *not* your friend!