What is the daily Spartan diet?

Could you please elaborate on what exactly constitutes the daily Spartan diet? I'm curious to know if it involves specific food groups, calorie restrictions, or perhaps a focus on certain nutrients. Is it a diet that emphasizes physical strength and endurance, or does it have other health benefits in mind? How does it compare to modern diets and nutrition recommendations? I'm eager to learn more about this ancient dietary practice and how it may apply to modern lifestyles.