MET Hours: Challenge Tracker

Exercise, measured in MET hrs

Only for iPhone

Free · Designed for iPhone. Not verified for macOS.

iPhone

Turn your workouts into the MET-hours the CHALLENGE Trial measured. Private by design: no accounts, no servers, nothing leaves your device. Always free. Exercise cut cancer recurrence risk by 28% in a landmark trial. This app tracks the exact unit that trial measured: MET-hours. The CHALLENGE Trial followed colon cancer survivors through a structured exercise program. The results, published in the New England Journal of Medicine in 2025: a 28% lower risk of cancer recurrence and a 37% lower risk of death. The trial set its targets in MET-hours, a clinical unit no fitness tracker reports. MET Hours calculates them for you, automatically. AUTOMATIC FROM YOUR APPLE WATCH Approve access once and your workouts log themselves: type, duration, energy, and heart rate. After each workout, a notification shows the MET-hours you earned, your weekly total, and your zone. Prefer manual entry? Every workout can be logged by hand instead. FOUR ZONES, ONE GOAL Your week climbs through Baseline, Active, Shield, and Peak Resilience. The Shield zone (20+ MET-hours) reflects the trial's target range. A clear weekly gauge shows exactly where you stand and what one more walk would do. VISCERAL FAT PROTOCOL (OPTIONAL) Track high-intensity sessions and your time in heart-rate zones 4 and 5, with zones calculated the same way Apple Watch calculates them: from your own resting and maximum heart rate. REPORTS FOR YOUR CARE TEAM Share a clean weekly or multi-week summary with your oncologist, physiotherapist, or family. PRIVATE BY DESIGN No accounts. No analytics. No servers. The app never connects to the internet. Your health data stays on your device, protected by Apple's on-device security. Always free. Built for colorectal cancer survivors. The trial studied a supervised three-year exercise program; this app is an educational tracking tool, not a medical device. Always consult your healthcare professional before beginning or changing an exercise program.

Ratings & Reviews

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A simpler, faster welcome. • Redesigned onboarding: the trial's result up front, a cleaner interactive demo, and a new "Your data is safe" screen • One tap now plays the whole sample week, with each workout coloured by the tier it reached • Refreshed About page with clearer explanations of how MET-hours are calculated • Design polish throughout

Version 1.1.5

The developer, NATHAN HORGAN, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    Accessibility

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Information

    Seller
    • NATHAN HORGAN
    Size
    • 2 MB
    Category
    • Health & Fitness
    Compatibility
    Requires iOS 17.6 or later.
    • iPhone
      Requires iOS 17.6 or later.
    • Mac
      Requires macOS 14.6 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.3 or later.
    Languages
    • English
    Age Rating
    13+
    • 13+
    • Learn More
    • Infrequent
      Medical Treatment information

      Contains
      Health or Wellness Topics
    Copyright
    • © 2026 Nathan Horgan
  • Developer Website
  • Privacy Policy