Fitness Calculators

A lightweight TypeScript library providing essential calculations for weightlifting and diet planning. Includes BMR (Basal Metabolic Rate), TDEE (Total Daily Energy Expenditure), macronutrient ratios, and various one-rep max estimation formulas.

Features

• BMR calculation using Harris-Benedict equation
• TDEE calculation with activity level and goal adjustments
• Macronutrient distribution calculator
• One Rep Max calculators:
  • Brzycki formula
  • Epley formula
  • Lombardi formula
  • O'Conner formula
  • Tuchscherer formula (RPE-based)
• Weight to lift calculator based on RPE, reps and 1RM

Installation

npm install fit-tools

Usage

This package can be used in Node.js applications and modern browsers through frameworks like React, Vue, Svelte, etc.

ESM Import

import { calculateBmr, calculateTdee, calculateMacros } from 'fitness-calculators';

CommonJS Require

const { calculateBmr, calculateTdee, calculateMacros } = require('fitness-calculators');

Examples

Calculate BMR:

const bmr = calculateBmr('female', 30, 65, 170);

Calculate TDEE:

const tdee = calculateTdee(bmr, 'moderate', 'maintain');

Calculate macronutrients:

const macros = calculateMacros(2000, 40, 30, 30);
// or using body weight for protein calculation
const macros = calculateMacros(2000, 40, 30, undefined, 65);

Calculate one rep max:

const orm = calculateOneRepMaxBrzycki(5, 100);

Calculate weight to lift:

const weight = calculateWeightToLift(5, 8, 100);

Important Note

This library does not include input validation. Users are responsible for validating inputs according to these guidelines:

• All numerical inputs should be positive numbers
• Weight values should be in kilograms
• Height should be in centimeters
• Age should be in years
• RPE values should be between 6.5 and 10
• Macronutrient percentages should sum to 100 if all three are provided
• Activity levels must be: 'sedentary', 'light', 'moderate', or 'heavy'
• Goals must be: 'moderateLose', 'mildLose', 'maintain', 'mildGain', or 'moderateGain'
• Gender must be: 'male' or 'female'

Contributing

Contributions are welcome! To contribute:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/new-feature)
3. Commit your changes (git commit -m 'Add some new feature')
4. Push to the branch (git push origin feature/new-feature)
5. Open a Pull Request

Please ensure your PR:

• Follows the existing code style
• Includes appropriate tests if adding new features
• Updates documentation as needed

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

If you encounter any issues or have questions, please:

• Check existing issues
• Open a new issue if needed

Authors

• Melisa Zorraindo - Website