As I posted in another topic, I really burned my soles on almost non-stop extended heat and roughness, with some stretches of sharpness. After a couple of days of minimal care for the soles, the painful tenderness is gone. I will probably always have a high sensitivity to rough and sharp, after all even when wearing shoes the texture can be felt pressing on the soles, but I am getting even more heat tolerance overall. Some of this repeats because I post each as its own topic... So as I mentioned, there are two kinds of heat... the slower but still progressively increasing burning heat that I referred to as "slow roasting" the soles; and, there is that much faster ow! HOT! heat that I referred to as "griddling" the soles, even without actual blisters from heat so fast (and then jumping off the heat before any risk of third degree burns). "Slow roasting" is good for the entire soles, for those who want to increase their standing heat capacity tolerance. The lack of any quick ow HOT! feeling allows longer durations of soles fully on the ground standing, and then as I have found that when heat relief methods are needed... I could roll on the soles very slowly. Not only did that distribute the heat just enough so any one spot wasn't burning too much, but it also allowed a much longer contact before rolling to another part of the soles, and as a positive side effect helped improve strength of the entire foot. When rolling on the soles still gets too hot, and remember this still builds up slowly over several seconds, then lifting a foot in the air helps with standing in one place. When it's too hot to stand, I could walk off the burning until the next time standing. I've mentioned this all before, but just for reference that even when it was becoming ow HOT! somewhat faster, I could still stand soles fully on the ground for between 10 and 15 seconds at a time, and could have rolled on the soles on that heat for minutes. At one particular light trail platform, that had lighter gray but slightly roughened concrete, I was able to stand on it for at least a minute, roll on the soles slowly for almost seven minutes, and the lift soles in the air for about two minutes. So nine minutes total... then it equalized. To continue heat training on that, I had to find another hot spot. In general that heat is excellent, but the actual really burned soles effect comes quickly! They don't unburn and they stay that way for the rest of the day, the tenderness lasts at least another day, and it's really not that much difference taking time off from barefooting or only doing light barefooting as when initially healing a heat blister. "Griddling" heat is the one many barefooters know. Step on the heat too soon, or if it's that hot even after off and on to get used to it: ow HOT! and either get off the heat, stay on the heat and roll on the soles more quickly, or lift the soles more quickly, but in all case walking on the heat needs to be done sooner and then it's how heat tolerant the soles last during walking. This is the heat that if it can't be stood on for much longer, the burning will get to close to that level with longer distance walking. This is the heat that can blister the soles, even if it takes several minutes, because the soles are never fully equalizing to the heat... and then even if they do, the friction on the burned soles is still HOT friction. Anyway, blah blah blah I need some heat. Both kinds of heat, preferably on a very hot day so I can start out earlier and then as close to or during the hottest afternoon hours. I need even hotter but still "slow roasting" heat to extended longer standing time and I need "griddling" heat for those shorter distances of so hot my soles are really burning. "Slow roasting" has a minimal risk of blisters, with the understanding the whole sole will be tender. "Griddling" heat more than likely causes blisters but then staying off the hottest heat didn't tenderize the rest of the sole. The main difference with the even hotter days is less time on "slow roasting" heat so they soles are not too tender to deal with the "griddling" heat. (Those in desert areas during summer probably want to be extra cautious: "griddling" heat can occur earlier in the summer days during high extreme to lower excessive heat that early morning, and as seen in some dancing shows where they showed the dancer working their feet too hard, they actually had a blackened ring forming around a blister that also broke... the obvious sign of third degree burns occurred on that circle. No amount of dedicated barefooting should be worth third degree burns... as much as I am dedicated to heat-training my soles to be as much as shoes, and then even includes some blistering hot asphalt to accomplish that, I will NOT third degree them at any time.)
You risk damage to your feet..make some shoes, its not difficult..like these babies for when your not allowed bare foot. a thin protective sole can be added for protection for certain conditions, but never, never risk damaging your feet, they have to last a life time.
I don't think I would go with any sort of barefoot sandal. It's either barefoot or flip flops. As for damage, it depends. There are photos of both women and men with various sizes of white spots on the balls of the feet that are flatter but still plenty rough and visible. That's not damage, that's a tough sole look, and I'm okay with having those soles and also seeing a barefoot women with those soles. Even tougher is that larger and raised callus, whether smooth or rough, that results from a reattached blister and not just increased friction. That's an every better tough sole that I want and looks even better on a barefoot woman. There are even photos of those that have soles that are still blistered... with proper draining and care, it will either reattach for that larger thicker callus, or it will peel away and leave a very shallow indentation that can take weeks to even a couple of months to fully close up. Damage is the scar lines that occur from larger healed cracks. Damage is soles so crusted, not toughened, that they start cracking instead of getting more tougher, and look unwashed instead of just the trapped blackened sole from longer distance asphalt barefooting. Damage is because they got a blackened char line around a blister, and it scarred especially when the blister also broke. That last one was even shown on a dancing show, where a teenage dancer was already ruining her soles with a broken blister and a blackened ring around it and still trying to continue dancing... showed the sole to the camera to see the damage, and just kept on going... and more than likely their soles will be scarred at least in that spot of the soles.