I know and train with several Japanese National sprinters and jumpers and above all their focus is on technique and biomechanics. They run alot of hills, tons of core, some olympic lifts, and an array of plyometrics (mostly one legged). My one friend who is 3x National Champion in the long jump and runs 10.4-5 does an enormous amount of hurdle and stick related drills. Like anything dealing with Japanese culture, they have read about alot of the different coaching methods and try to perfect those techniques. Both the top male and female sprinters focus their training on very minute aspects of foot placement during the start. For example Chisato Fukushima and Masashi Eriguchi use a stick from stick drills, and place it on the line of the start. Every start they are supposed to just clip the stick in order to minimize air time.
Lastly, developmentally there are tons of running clinics and teams here and almost all of them have national level athletes or former athletes teach those kids. Japan has a long, long tradition of valuing the craft.
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