Privacy Policy
Effective date: June 16, 2026
1. Who We Are
BioStride ("we", "us") is operated by Mark Potyagaylo (עוסק מורשה, Israel).
Contact for privacy matters: [email protected]
2. Data We Collect
2.1 Account data
- Name and email address (provided at registration)
- Google profile data if you sign in with Google (name, email, avatar)
- Account preferences: language, preferred sports, auto-adapt setting
2.2 Intervals.icu credentials
- Your Intervals.icu Athlete ID and API key — stored encrypted in our database
- Used exclusively to read and write your training data on your behalf
2.3 Training data (read from Intervals.icu)
- Training activities: type, date, duration, distance, heart rate, power, load (TSS)
- Wellness data: weight, resting HR, sleep score, HRV, fatigue (CTL/ATL/TSB)
- Sport settings: FTP, pace zones, HR zones
- Race calendar events you add to BioStride
2.4 Usage data
- Training plans generated and approved by you
- AI coach chat history (stored to provide context in future sessions)
- Bug reports submitted via the in-app reporter
- Standard server logs: IP address, browser user-agent, timestamps
3. How We Use Your Data
- Training plans: your activities, wellness, zones, and race goals are sent to Anthropic's Claude AI to generate personalised plans.
- Plan adaptation: missed workouts and compliance data are used to automatically adjust your plan.
- Sync: approved plans are written back to your Intervals.icu calendar.
- Service improvement: aggregated, anonymised usage metrics to improve the AI prompts and features.
- Transactional email: account verification, password reset, plan notifications — sent via Resend.
We do not sell your data. We do not use your data for advertising.
4. Third-Party Services
| Service | Purpose | Data shared |
|---|---|---|
| Anthropic (Claude AI) | Generate training plans and coaching advice | Training data, wellness metrics, race goals |
| Intervals.icu | Read/write training data | Approved workout events |
| Resend | Transactional email | Email address, email content |
| Payment processor | Payment processing (Pro subscriptions) | Email, billing details |
| Google (OAuth) | Social sign-in | Name, email, avatar |
5. Data Storage and Security
- Data is stored on secure servers.
- Intervals.icu API keys are stored encrypted.
- Connections use HTTPS/TLS.
- Passwords are hashed with bcrypt and never stored in plaintext.
- Regular database backups are retained for 30 days.
6. Your Rights (GDPR)
If you are in the European Economic Area, you have the right to:
- Access — request a copy of the data we hold about you.
- Rectification — correct inaccurate data.
- Erasure — delete your account and all associated data.
- Portability — receive your data in a machine-readable format.
- Objection — object to processing based on legitimate interests.
To exercise any of these rights, email [email protected]. We will respond within 30 days.
7. Data Retention
- Account data is retained as long as your account is active.
- After account deletion, data is permanently deleted within 30 days.
- Server logs are retained for 90 days.
- Anonymised, aggregated analytics may be retained indefinitely.
8. Cookies
BioStride uses only essential cookies required for authentication and session management. We do not use advertising or tracking cookies. No cookie consent banner is needed.
9. Children
BioStride is not directed at children under 16. We do not knowingly collect data from anyone under 16.
10. Changes to This Policy
We may update this Privacy Policy. We will notify you by email at least 14 days before material changes take effect.
Questions? [email protected]