Well, for starters, he is around 10-12. Not many 10-12 year olds can stay up 24/7 questing across an expansive ocean, fighting bosses that are over five times his size, etc. For a kid who looks like he lacks muscle, he can lift quite a bit (i.e. pigs and to-be sages). He also has the dexterity to fight bosses and onslaughts of enemies with no break period. Plus, let's not forget he fought the King of Evil and a soul-sapping squid.
Then (Which I'm not sure if he is or isn't) his descendant spent nights studying train operation and spending countless hours practicing how to operate the train across the expansive overworld of Hyrule (Well, with all of the tracks dissipating, his practice space started to grow smaller). Plus, on top of that, being lectured about the land his fore-fathers of two generations ago settled on with paper cutouts (Or were they pencil drawings?).
I mean, the Hero of Winds lived a somewhat similar life to the Hero Chosen by the Gods. Both were farm boys (But the Hero of Winds actually had family members: a sister and a grandmother), both were very acquainted to the village people, etc. However, the Hero Chosen by the Gods was more into ranch work while the Hero of Winds did more of just hanging around, observing the Outset Island pigs, and doing small chores. However, the Hero Chosen by the Gods was around 17-19, so he had a more built body that could support longer work. Remember, the Hero of Time also fell asleep while listening to 4 hour lectures.