I thought I would resurrect this thread rather than my own more recent one on the same topic because I thought it would be interesting to find out what people's subsequent experiences were with this. I particularly like the poster's description of the stiffness as feeling like her soles are too full - that may not be the exact wording, as Tapatalk doesn't let me look back while typing a reply. But that is exactly the feeling I get. [edit, looking back I remembered this a bit wrong - she said her feet feel as if they had been crammed into a small space, whereas I would probably describe it that the feel themselves are somehow a bit 'pumped up')]
My stiffness has definitely got a bit worse since I increased my distance rather quickly to do a 5k parkrun, and maybe a bit since I upped my cadence a few weeks ago. It doesn't bother me while walking or running at all - just for the first few steps after resting, either in bed or just sat down. if I lie in bed and wiggle my feet around before getting up, it doesn't hurt at all to move the feet and the stiffness feels less when I do get up, though it is still there. A few 10-20?) steps, and standing up on forefoot and back a few times, is enough to get rid of it. When it isn't there, it isnt there. It's not just 'less'.
Just to annoy the anti-earthers<g>, if I sit out in the garden with bare feet on the grass, I don't get the stiffening up effect when I get up.
My impression is that it may be less after I have worn minimal shoes with socks and a little bit of cushion (like Vivos with the insole left in) rather than actual bf or Sockwas, and more if more hard surfaces, so I'm wondering if it is related to actual irritation of the sole rather than just bone/muscle/ligament development?
I'm not getting a lot of sympathy as you can imagine -! 'Your feet hurt - oh, what was it you were doing yesterday? Running with no shoes on? Well, duuuh...'