Mifflin-St Jeor BMR: Gold-standard clinical predictive equation for Basal Metabolic Rate: $\text{BMR} = 10W + 6.25H - 5A + s$ (where $s = +5$ for males, $-161$ for females).
Total Daily Energy Expenditure (TDEE): $\text{TDEE} = \text{BMR} \times \text{PAL}$, incorporating the physical activity level multiplier ($1.2\text{ to }1.9$).
Karvonen Heart Rate Formula: Computes cardiovascular exertion training zones via heart rate reserve: $\text{Target HR} = \text{HR}_{\text{rest}} + (\text{HR}_{\max} - \text{HR}_{\text{rest}}) \times \% \text{Intensity}$, where $\text{HR}_{\max} \approx 220 - \text{Age}$.
Operating Instructions: Adjust biometrics (weight, height, age, gender, activity level) to compute metabolic burn rates, macronutrients, and cardiac zones.