Last updated: July 2026
Upon registration: email address, password (stored encrypted), name. Optional: date of birth, weight, height, gender for training calculations.
If you connect integrations, we process the following data — exclusively for your personal coaching:
Training plans, nutrition recommendations, shopping lists, recovery analyses, supplement recommendations. These are calculated from your data and stored.
All data is processed exclusively for your personal coaching:
Processing is based on your explicit consent (Art. 6(1)(a) of the Datenschutz-Grundverordnung (GDPR — the EU General Data Protection Regulation)). For health data, Art. 9(2)(a) GDPR applies. You may withdraw your consent at any time.
We do not sell data. There is no advertising.
We do not share your data with third parties for advertising or sales purposes. Data is shared exclusively with carefully selected processors that we require to operate the platform: our hosting provider (see section 6), the providers of the AI models used for coaching (see section 7.1 — only with your explicit consent), and the error-diagnostics service (see section 7.2). Data processing agreements pursuant to Art. 28 GDPR are in place with all processors.
In addition, data is exchanged between you, the ATHRON platform, and the integrations you have connected (Garmin, TrainingPeaks, etc.). You control the connection to each integration yourself via the settings.
ATHRON is hosted on Hetzner Online GmbH servers in Germany. Your data is stored on German/European servers. For AI-powered coaching, certain data is transferred to processors in the USA (see section 7.1) — this third-country transfer (USA) is based on EU standard contractual clauses (Art. 46(2)(c) GDPR) and your explicit consent (Art. 49(1)(a) GDPR). Beyond that, no transfer to third countries takes place.
For personal coaching, ATHRON uses AI models from external providers acting as processors: Anthropic PBC (USA) and OpenAI LLC (USA). Only if you have given consent in the app is the following data transferred to these providers for that purpose:
Purpose: exclusively your personal coaching (training planning, nutrition recommendations, coach responses). Legal basis: your explicit consent (Art. 6(1)(a) GDPR; for health data, Art. 9(2)(a) GDPR). The transfer to the USA is based on EU standard contractual clauses and data processing agreements (DPA). Use of your data for training the AI models by these providers is contractually prohibited under the data processing agreement.
Without this consent, no data is transferred to the AI providers — the corresponding coach features remain disabled. You can withdraw your consent at any time in the app under Settings → Privacy & Legal, with effect for the future.
To diagnose app crashes and errors, ATHRON uses the service Sentry (Functional Software Inc., cloud region Frankfurt). In the event of an error, the following is transmitted: technical stack traces, device and operating system version, app version, and a pseudonymous athlete ID. Not transmitted: email address, plaintext passwords, coach conversations, recovery values (HRV, sleep, Body Battery), and integration tokens — these are replaced by a filter before transmission ([redacted]).
Legal basis: legitimate interest in a stable app (Art. 6(1)(f) GDPR). Retention period in Sentry: 90 days, followed by automatic deletion. You may object to crash reporting by contacting [email protected].
Your data is stored as long as your account is active. After account deletion, all personal data is irrevocably deleted within 30 days.
Contact for all requests: [email protected]
ATHRON uses technically necessary cookies for authentication (session cookie). They are required for operation and do not need consent. We do not use advertising cookies and we do not share data with third parties for advertising purposes.
Product analytics — only with your consent. If you opt in, we collect anonymous usage data (e.g. which areas and features are used) to improve ATHRON. For this we use PostHog, operated on an EU instance (data centre in Frankfurt am Main, Germany). A data processing agreement pursuant to Art. 28 GDPR is in place with the provider. No transfer to third countries outside the EU takes place.
Legal basis is your consent pursuant to Art. 6(1)(a) GDPR. Product analytics is off by default: without your consent, no analytics script is loaded and no analytics cookies are set.
No health data. No health, recovery, lab or DNA values and no direct identifiers (e.g. email) are included in product analytics. A technical safeguard blocks the transmission of such data.
Withdrawal. You can withdraw your consent at any time with effect for the future — in the app under Settings → Privacy & Legal → Consents → Analytics (desktop: Settings → Privacy). After withdrawal, no further analytics data is collected.
Retention. Analytics data is stored only for as long as necessary for product improvement and is deleted afterwards.
This privacy policy may be updated when the platform changes. The current version is always available at athron.app/legal/privacy/en.