What we are making
A free browser-based workout analyzer: import FIT or TCX activity files, use your existing zone limits, inspect weekly and workout totals, then export a table or chart. Files are processed locally and are not uploaded. The supporting library includes a free six-page illustrated guide and diagrams. A future iOS App is in exploration; it has not launched. The check kit helps you inspect the zone view or a method mismatch, record unresolved items, and take a full checklist to a support conversation. It does not connect to or test your device.
Editorial status
AI-assisted product and content draft. Official sources were checked on September 14, 2026. Independent professional review and hands-on verification of the device instructions have not yet been completed.
We do not measure your thresholds, diagnose readings, prescribe workouts or claim that one formula works for everyone. Sources listed here do not endorse this project.
Primary references
- CDC · Measuring activity intensity
Relative effort and the broad, not zone-specific, talk test.
- Apple · View Heart Rate Zones
Apple documentation: watchOS 26. Checked 2026-09-14; hands-on verification pending.
- Apple · Customize workout views
Workout view selection in watchOS 26. Other versions can use different navigation; not tested on a physical watch.
- American Heart Association · Target heart rates
Age-based averages are general guidance, not individual measurements.
Workout file formats and software
Descriptive analysis of timestamped records, not device verification. See the calculation method and exclusions. FIT decoding uses the locally bundled fit-file-parser 5.0.2, with buffer 6.0.3, base64-js 1.5.1 and ieee754 1.2.1. License notices accompany the distributed browser module; no CDN or remote parsing service is used.
Safety boundary
Educational draft, not medical advice or a training prescription. This guide does not interpret symptoms or measure your exercise thresholds. Seek qualified advice for symptoms, conditions or medication-related questions.
Publisher and contact
Independent Zone 2 Field Guide project. Use the feedback page for anonymous product choices to help improve the site. Do not submit personal health information. Formal publisher details and professional content review remain pending.
You can send anonymous product choices through the feedback page. A public support address is being prepared; anonymous submissions cannot receive a personal reply.