Know your true
training state.

Most apps dump metrics and leave you guessing. Ryun differs in four ways:

• Chat-first analysis. Ask about your training in plain language and get answers grounded in your actual data. No dashboards to learn, no charts to decode.
• A memory layer that compounds. Ryun remembers your goals, injuries, race targets, and patterns from every conversation. Day 90 advice is fundamentally smarter than day 1.
• Plans that adapt to your real state. If your HRV drops or your resting HR spikes, Ryun proposes adjusting tomorrow’s session and asks you to confirm before anything changes. You stay in control.
• Open, peer-reviewed science. Every metric uses published formulas (Daniels, Banister, Seiler, Plews/Altini, Gronwald). Ask Ryun “why did you change my plan?” and get a real answer — never a black box.

Every conversation, session, and physiological signal becomes a structured fact in your athlete memory: goals, training patterns, biomechanical flags, recovery responses, race targets. The AI references this memory in every future answer — so day 90 advice is fundamentally smarter than day 1. Unlike chat tools that forget context after each session, Ryun’s memory persists and compounds across weeks, months, and seasons.

Ryun runs every session through a science engine that turns raw device data into clear signals:

• Pace zones — personalized easy, tempo, threshold, and race paces, recalibrated after every hard effort (Daniels VDOT, %LTHR heart rate zones).
• Fitness, fatigue, and form — how trained you are, how tired you are, and whether you’re race-ready (Banister CTL / ATL / TSB, Coggan TSS for normalized load).
• Recovery state — nightly HRV trend and how your nervous system handled today’s session (Plews/Altini lnRMSSD with rolling baseline, DFA-α1 for autonomic state).
• Polarized intensity — whether your easy runs stayed easy and your hard sessions hit their target zones (Seiler 80/20, aerobic decoupling).
• Injury risk — early warning when training load is climbing too fast (ACWR, ramp rate).

Ryun’s readiness model combines those signals to decide what kind of session you’re ready for today. All formulas are deterministic and peer-reviewed — never generated or hallucinated by an LLM. Ryun explains every result in plain language, grounded in your athlete memory and full training history.

Ryun’s chat is a conversational interface to your training data and the science engine. It explains training load trends, interprets HRV patterns, assesses race readiness, and answers questions about your sessions — always grounded in your actual numbers and verifiable formulas. It translates complex metrics into clear guidance, but the science behind every answer is open and inspectable. For high-stakes medical decisions, always consult a sports physician.

Garmin Connect with automatic sync — your full training history imports on day one, and new sessions sync automatically. Wahoo, Suunto, and more coming soon.

Yes — Ryun works over MCP, so you can connect your Garmin running data to Claude or ChatGPT and ask questions right where you already chat. The difference to MCP-only bridges: the science lives in Ryun. DFA-α1 thresholds, recovery state, and your athlete memory are computed by Ryun’s own engine — MCP is an optional window into it, never a requirement, and you don’t need an extra AI subscription to use Ryun itself.

No — your training data, conversations, and biometric signals are never used to train, fine-tune, or improve AI models, and Garmin-provided data is contractually excluded from any model training. Ryun is operated from Germany under EU GDPR; your data is never sold, shared, or exposed to advertisers or third parties. Internal access is limited to engineering staff for narrowly-scoped debugging. AI providers are used strictly for inference, with zero-retention or no-training configurations applied where offered. See the AI Product Terms for the full per-provider breakdown and the Privacy Policy for the subprocessor list.

When you delete your account, your personal data — training history, conversations, athlete memory, biometric signals — is erased from Ryun’s active systems. AI inference logs are kept short-term for debugging and then deleted. Server logs are retained 30–90 days for security purposes. You can request export or full deletion at any time. The full retention schedule is detailed in the Privacy Policy.

All conversations and biometric data are encrypted in transit and at rest. Garmin integrations use official OAuth — Ryun never stores your device-platform credentials. Health data is processed only with your explicit consent (Art. 9(2)(a) GDPR), and you can withdraw consent at any time in Settings. Full technical details are in the Privacy Policy and AI Product Terms.

Email support@ryun.app or message us in the Ryun Discord with the conversation ID. Reports are reviewed and used to improve safety guardrails. For any urgent medical concern, please consult a sports physician — Ryun is a training-guidance tool, not a medical device, and AI outputs are advisory only.

Join the Ryun Discord — it’s the fastest channel for feedback, bug reports, and feature requests. The team reads every message and ships changes weekly during the beta. You can also email support@ryun.app for anything you’d rather keep private.