Your basal metabolic rate (BMR) is the calories your body uses at complete rest for vital functions — heartbeat, breathing, cell repair. BMR is the largest slice of daily burn (roughly 60–70% for many). It’s driven by body size, muscle, age, and genetics more than by "boost" tricks. Supporting it means preserving muscle (strength training, adequate protein) and avoiding very low intakes that suppress it over time.
Key facts:
- BMR = rest burn for vital functions
- ~60–70% of daily total
- Driven by size, muscle, age
- Protect with muscle + food