The Spartans are an extreme example of a Warrior Culture where All male children began training at 7 years old, but most Societies modern, medieval and ancient had a Warrior Class. In the middle ages, Knights (members of the ruling classes) were often tutored individually before taking their place in the military, while foot soldiers (lower classes) were often "drafted" and trained in brutal camps.
I prefer to think that Elven Martial Training was more like the Warrior Monks of the Orient, such as in Shaolin and Tibetan monasteries, or the Samurai. As such their Martial Training was to benefit Mind, Body, and Spirit as well as for Defense. If you want to see how they did it, just watch a few Historical Kung Fu dramas

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