How Keystone Works

Keystone turns Strava, archive, and FIT activity data into auditable endurance physiology: LT1/LT2, zones, durability, altitude context, load, CdA analysis, and ride-level evidence for each athlete.

1. Create a beta profile and upload data

New beta athletes can start with Strava Connect or manual onboarding. Strava Connect imports supported cycling, running, and swimming activities from the last 3 years and supports future sync. Manual onboarding uses the beta signup code, email for magic-link login, the original Strava export ZIP, and the one-time recovery code shown after import. Use manual ZIP/FIT/FIT.GZ files for full first-time ZIP onboarding, no-OAuth setup, archive completeness, or later gaps. Keystone stores activity metadata, time-series streams, laps, and computed features for each athlete separately.

2. Process training signals

After import, Keystone computes deterministic analytics such as best efforts, steady-state blocks, heart-rate drift, time in zone, altitude-normalized power, LT1 and LT2 estimates, and threshold snapshots over time.

3. Surface analysis in the app

• Dashboard shows current LT1/LT2, load direction, durability watch list, recent meaningful changes, data quality gaps, and the next things to inspect.
• Daily Snapshot shows what a selected ride demonstrated, with links into the full ride detail.
• Ride views show streams, modeled analysis, interval blocks, lactate, nutrition, Aero Lab, Course Plan, and feature summaries.
• Trend views show guided longitudinal analysis across thresholds, power-duration, durability, weekly volume, and related training signals.

4. Explain physiology and durability

Keystone keeps canonical sea-level-equivalent power thresholds separate from observed-HR anchors and durability context, then shows the evidence behind threshold changes, late-ride drift, altitude strain, heat strain, lactate readings, and logged fueling or sodium.

5. Support coach review

Keystone supports beta memberships for multiple athletes. Owners manage their own profiles, coaches can review and edit assigned athletes where mutating routes allow, and viewers or guest links remain read-only.

Data flow summary

1. Athlete connects Strava for a 3-year import/future sync or creates a manual beta profile with the invite code and email.
2. For manual archive setup, athlete uploads the original Strava export ZIP with supported FIT/FIT.GZ entries and saves the one-time recovery code.
3. Keystone imports activity streams and metadata.
4. Analytics engines compute ride-level and athlete-level features.
5. The app renders dashboards, rides, trends, lab data, lactate context, heat/fueling context, CdA tools, and durability diagnostics for the selected athlete.