I have observed (anecdotally) an increase in calf/achilles pain and knee pain reports in high school runners transitioning between XC and track meets in which t

I have observed (anecdotally) an increase in calf/achilles pain and knee pain reports in high school runners transitioning between XC and track meets in which they're wearing ultra-minimalistic spikes with negligible - often negative! - heel-toe drop, and training in high-stack "cloud shoes" with enormous amounts of exotic super-cushioning foam. I think this is particularly unhelpful when marketing the same shoe design that has essentially no material under the instep or heel to elites who have the endurance and form to be poised on their toes with negligible heel contact during an entire 10k to 15-year-olds who will start off with grand ambitions and then be slogging it in for the latter two laps of the 1600.. I definitely agree that runners using these "maximalist" shoes exclusively are likely to experience more foot injuries if they ever need to transition away from them. My coaches (from as far back as...two decades ago, yikes) had us do strides on the football field barefoot, as well as occasional speed workouts on the track in spikes or spike flats to ensure that we were not only conditioning our major leg muscle groups but also smaller muscles and ligaments in the feet. If you only ever train to go straight forward with even, highly cushioned footfalls, and step in a pothole or on a rock when your muscles are at their weakest, it's not good. That said, for long, slow, distance days, I love me some cloud shoes. I just make sure to switch them up with minimalist flats for speed work and tempos once in a while, and to get some barefoot strides in when I have access to good grass.