Balls!!!
If I'm not mistaken... the Greeks invented Huevosios Muffinistis to fuel their troops before battle.
The Roman Empire, after conquering the Greeks, assimilated this portable meal into their rank and file as a staple.
Legend has it that the 300 Spartans carried Huevosios Muffinistis in fanny packs [Packis Fannizia] into battle with the Persians.
True Story.