If you’ve met a Mongolian nomad, or someone from Mongolia, you might notice they are hardy and strong people.
Culturally Mongolians used to live as nomads and thus a hard environment leads to tough people. Besides climate and weather the foods that Mongolians eat are calorie dense with a lot of proteins which does help with muscle and bone development.
Meats such as beef, mutton, and goat are rather cheap and consumed greatly. There is plenty of organic milk and dairy products, so it helps with strong muscles and bones.