I'm just curious to know if once the skin on the soles of the feet has thickened and toughened up is it possible to lose that conditioning if you stop running completely barefoot? What I mean is, is it a "use it or lose it" sort of situation or is it that once you've conditioned the plantar skin and it becomes thicker and less sensitive it stays that way indefinitely. Curious what you experienced BFRs think. Do some of you who live in colder climates (and use footwear during the winter) have to go through a period of reconditioning once spring rolls around?