What is Spartan lifestyle?

Could you please elaborate on the concept of the "Spartan lifestyle"? Is it a reference to the ancient Greek city-state of Sparta and their military discipline, rigor, and self-reliance? If so, how does this translate into a modern-day lifestyle choice? Does it involve strict physical training, a minimalist approach to possessions, or perhaps a focus on resilience and perseverance in the face of adversity? I'm curious to understand the principles and practices that define this way of living.