Activity Detail & TSS

Tap any activity in your feed to open its detail view — the full picture of a single session, plus the score that feeds your training-load model.

Full metrics#

The detail view shows the complete set of metrics for the session: duration, distance, pace or speed, elevation, heart rate, power, cadence, and more, depending on the sport and what your device recorded.

Stream charts#

Where the data is available, Aithlo renders stream charts that plot how each metric changed over the session:

• Power — your output through intervals and climbs.
• Heart rate — how your effort rose and recovered.
• Cadence — your turnover or stride rate.
• Pace — your speed across the activity.

These come from Strava's activity streams, so the more your device captures, the richer the charts.

How TSS scoring works#

Every activity gets a TSS (Training Stress Score) automatically — a single number combining intensity and duration that captures how demanding the session was. Aithlo scores it using the best available method, falling back through a priority order depending on what data exists:

1. Power — the most accurate, used whenever power data is present.
2. Heart rate — used when there is no power.
3. Pace — used for runs (and similar) without power or usable HR.
4. Swim speed — used to score swims.
5. Fallback — a sensible estimate when none of the above are available, so no session goes unscored.

This means you get a consistent training-stress number across every sport, whatever your gear.

Why it matters#

Each activity's TSS feeds directly into your training-load model — your Fitness (CTL), Fatigue (ATL), and Form (TSB). That is what powers your readiness gauge and your trends. Learn the terms in the Training Science Glossary, and see how the load builds over time in Training Load & Trends.