Ruck Marching Calorie Expenditure Calculator

Overview

A clean, efficient, and data-driven utility that allows fitness enthusiasts, hikers, and tactical athletes to calculate the estimated calorie expenditure for rucking. This tool focuses on the relationship between body weight, rucksack weight, distance, pace, and terrain.

Technical Implementation Constraints

• Architecture: Single-file HTML/CSS/JS architecture.
• Statelessness: No use of localStorage, sessionStorage, or cookies. The application must perform all calculations in-memory. If a URL-based sharing system is needed, use Base64 encoded hash parameters.
• Browser Environment: Strictly sandboxed for iframe compatibility (no alert(), confirm(), or prompt()). Use custom HTML modal components for user feedback.
• Dependencies: Use Tailwind CSS via CDN for styling. Use a lightweight graphing library (e.g., Chart.js CDN) if data visualization is included.

Detailed Feature List

1. Input Module:
   • User Specs: Body weight (lbs/kg), Ruck weight (lbs/kg).
   • Activity Specs: Total distance, Total time, Terrain type (Flat, Hill, Rugged).
2. Calculation Engine:
   • Dynamic MET (Metabolic Equivalent of Task) adjustment logic based on the "load-to-body-weight" ratio.
   • Real-time updates as user moves sliders or types inputs.
3. Result Dashboard:
   • Total Calorie Burn.
   • Calories per Mile/Km.
   • Metabolic Impact visualization.
4. Export Options: Browser-native print functionality to save the workout summary as a PDF.

UI/UX Design

• Palette:
  • Background: bg-slate-50 (Clean, light aesthetic).
  • Primary: text-emerald-600 (Energetic, healthy).
  • Accent: bg-blue-600 for action buttons (Professional, trustworthy).
  • Typography: Sans-serif (Inter or system-stack) for readability.
• Layout:
  • Header: Descriptive, clean title with a brief subtitle.
  • Main Section: Split-pane layout. Left side: Form inputs with clear labels. Right side: Live result readout and small graph.
  • Cards: Modern card-based design with subtle shadows (shadow-sm hover:shadow-md) and rounded corners (rounded-xl).
• Micro-interactions:
  • Smooth CSS transitions (transition-all duration-300) for input field focus states.
  • Counting animation for calorie results (incrementing numbers when the calculation updates).

Implementation Directives

• Use input type="number" with min="0" attributes for all data points to ensure valid data entry.
• Ensure all units (lbs/kg, miles/km) have a clear toggle or selector that recalculates values instantly.
• The design must be 100% mobile-responsive, stacking inputs vertically on screens smaller than 768px.