💪 Fitness Fundamentals
Understand the core principles of physical fitness, from cardiovascular health to flexibility, and build a solid foundation for your fitness journey.
Fitness Guides, Workouts, Nutrition & Calculators
Science-backed fitness content written by certified trainers and nutritionists. Whether you're a complete beginner or an experienced athlete, FitAuthority provides the evidence-based guidance you need to train smarter and live healthier.
🏋️ Workout Training
Structured workout programs for every goal — from strength training and cardio to home workouts and gym routines, with progressive overload built in.
🥗 Nutrition & Diet
Evidence-based nutrition guides covering macronutrients, meal planning, and diet strategies for weight loss, muscle gain, and overall health.
🧮 Fitness Calculators
Free, evidence-based health and fitness calculators. Instantly estimate your BMI, BMR, daily calorie needs, body fat percentage, and ideal weight.
🎯 Fitness Goals
Goal-specific training and nutrition strategies. Whether you want to lose weight, build muscle, improve endurance, or increase flexibility.
⭐ Why Trust FitAuthority?
Our content is written and reviewed by certified personal trainers (CPT), registered dietitians (RD), and sports science researchers. We cite peer-reviewed studies and follow evidence-based guidelines from organizations like the ACSM and NSCA.
- ✅ Evidence-based content
- ✅ Written by certified professionals
- ✅ Regularly updated
- ✅ No pseudoscience
Featured Fitness Calculators
Use our free calculators to understand your body metrics and plan your fitness journey with precision. Each calculator includes detailed explanations of the formulas used, their limitations, and expert guidance on interpreting results.
| Calculator | What It Measures | Best For |
|---|---|---|
| BMI Calculator | Body Mass Index based on height and weight | General health screening |
| BMR Calculator | Basal Metabolic Rate (resting calories) | Diet and nutrition planning |
| Calorie Calculator | Total Daily Energy Expenditure (TDEE) | Weight management |
| Body Fat Calculator | Estimated body fat percentage | Body composition tracking |
| Ideal Weight Calculator | Healthy weight range for your height | Goal setting |
About FitAuthority
FitAuthority was created to be the most comprehensive and trustworthy fitness resource on the web. We believe that everyone deserves access to accurate, science-backed fitness and nutrition information — without the hype, misinformation, or product pushing that plagues the fitness industry.
Our editorial team follows strict content guidelines: every claim is supported by peer-reviewed research or expert consensus from leading health organizations. We cover everything from foundational fitness concepts for beginners to advanced training programming for experienced athletes.
Whether you're calculating your macros for the first time, designing a strength training program, or simply trying to understand what "fitness" really means, FitAuthority is here to guide you with clarity, depth, and scientific integrity.