What Is Activity Deep Dive?
Activity Deep Dive lets you explore every detail of your workout by loading FIT, TCX, or GPX files directly in the browser. Instead of relying on the summary screens of Garmin Connect or Strava, you get access to the raw, second-by-second data: heart rate curves, pace fluctuations, cadence patterns, power output, elevation changes, and GPS tracks. This is especially valuable for coaches and data-driven athletes who want to analyze specific segments — like how your heart rate responded during a hill repeat, or whether your cadence dropped in the final kilometres of a marathon.
Interactive Charts and Data Visualization
The tool renders your activity data as interactive Chart.js graphs. You can overlay multiple metrics — for example, heart rate and elevation on the same time axis — to see how terrain affected your effort. Hover over any point to see the exact value at that moment. Zoom into specific intervals to study your pacing strategy during a race or the recovery pattern between intervals. For wheelchair athletes and handcyclists, the tool processes the same FIT data fields but presents them in context: push frequency instead of running cadence, and handcycle power metrics where available.
Common Mistakes in Post-Activity Analysis
Focusing only on averages hides important patterns. Your average heart rate might be 155 bpm, but Deep Dive reveals you spent 12 minutes above 175 bpm during hill sections — crucial information for understanding cardiac drift and recovery needs. Another common mistake is ignoring GPS artifacts: tunnels, dense tree cover, and tall buildings cause GPS spikes that distort pace and distance calculations. Look for sudden unrealistic speed jumps in the data. Finally, comparing absolute numbers between different conditions (hot vs. cold weather, flat vs. hilly terrain) without accounting for environmental factors leads to misleading conclusions about fitness progress.
About This Tool
Activity Deep Dive replaces 7 separate converter and analyzer pages. Upload a FIT, TCX, or GPX file to get a complete picture of your workout — from elevation gain to HR zone distribution — and export to any supported format.
Supported formats
FIT (Garmin, Suunto, Wahoo), TCX (Garmin, Polar), GPX (universal GPS standard). Export to GPX, TCX, or CSV for analysis in other tools. All processing happens in your browser — your data never leaves your device.