Health & Fitness Guides

Evidence-based guides to help you understand the science behind sleep, nutrition, recovery, and training.

Heart Rate Variability (HRV) Explained

What HRV is, what a good score looks like by age, how it connects to recovery, and proven strategies to improve it.

Macro Tracking for Beginners

How to count macros, calculate your protein, fat, and carb targets, and avoid the most common tracking mistakes.

Sleep Stages Explained

Understand light sleep, deep sleep, and REM -- how much you need of each, what affects them, and how to improve sleep quality.

How to Calculate Your TDEE

Step-by-step guide to calculating Total Daily Energy Expenditure (TDEE) using clinically validated formulas, with activity multipliers and calorie goals.