The physics behind martial arts (aka weeaboo fightan magic)

In my campaign setting, really more of a cosmology at this time, martial classes have "martials arts" or less charitably "weeaboo fightan magic." The reason? Having Conan the Barbarian adventuring alongside Naruto is stupid. Since my cosmology does not make an arbitrary distinction between magic and non-magic, but defines nature and technology as types of magic, it is natural for martials to develop wuxia and other capabilities that would be considered supernatural in real life. In fantasy land, this is par for the course.

Siegfried from Norse mythology

The physics behind this are simple and not autistic (no offense to people with autism). Magic is responsible for basic features of reality like trees growing, birds flying, and lightning strikes. Thus, people who train really, really hard are capable of achieving superhuman feats. If they train really hard in athletics, then eventually they will learn how to fly, move so fast they teleport, etc. If they train really hard in handling animals, they will learn how to literally speak with animals. If they train really hard in public speaking, they may convince pretty much anything. If they train really hard in theft, they may steal character traits like identities and skills. If they train really hard in stealth, they may learn to become effectively invisible and vanish from sight. And so on.

I take cues from recent 3pp like Path of War and Spheres of Might. Unfortunately, they are written for Pathfinder, which I hate due to its absurd and over-complicated rules. At this point I am pretty much doomed to rely on Risus, since it is literally the only RPG that explicitly allows fantasy combat between martials and casters rather than consigning martials to the trash bin. 13th Age is also good, but so perfectly designed that I cannot think of anything to blog about.