Yeah, it might just be one of those days, mid training block carrying fatigue. Yasso 10x800 on Fri so will see how they feel on the track after a gentler week.
My paces are getting slower in this marathon block, past 3 weekends I’ve done 18, 20, 20 mile long runs so hoping it’s the fatigue. I’m going to dial the distance back and try and increase the speed for a few weeks, I really want my marathon pace to feel “easy” on the day.
Sounds like further testing required