Ask a person.

Your Strength Index and your Engine Index are graded separately against published population standards, then combined with a harmonic mean. The harmonic mean is why being excellent at one half does not carry the number: the weaker side pulls the total down.

Every metric, and the research behind it, is written up at hybridaf.app/science. That page also states plainly which parts are our own design choices rather than published science.

Engine and grind are read over rolling windows, so they fall when the work stops. Strength is anchored to your best lifts and does not decay on its own. A drop almost always means the engine side has gone quiet, and the score page names which pillar is lagging.

No. If there is no wearable data, the engine side falls back to a recent hard run, then to HYROX results. A wearable makes recovery sharper, it is not required to get a score.

No. HYROX is one supported goal type. The app is built for anyone who lifts and runs seriously and wants to know whether the split is working.

Apple Health (in the iOS app), Strava, and Google Calendar. You can also import your lifting history as a CSV from Strong or Hevy, and log anything by hand.

WHOOP, Oura, Fitbit, and Garmin are not connected yet. They are coming, and we will not pretend otherwise until they are switched on. Workouts and readings they save to Apple Health still come in through Apple Health.

Google Fit and Health Connect are Android services, and hybridAF is an iPhone app, so neither connects.

This is almost always a token revoked on Strava's side. Reconnect from Profile, Connections, and recent activities backfill. If it drops again within the week, email us with the date it stopped.

Apple Health only works inside the iOS app, not the website. Check that permissions are granted in the iPhone Settings app, under Privacy and Security, Health, hybridAF, then run the sync again from Profile. iOS grants each data type separately, so a partial sync usually means one type is still switched off.

No. hybridAF is an iPhone app, and your training lives there. The website holds the guides, the science and the free tools, like the VO2max calculator and the HYROX splits analyzer.

Both live in Profile, under the account section. Export downloads everything we hold on you. Delete removes your account and the training data attached to it. Deletion is immediate and cannot be undone.

No. Not sold, not shared with advertisers, never used to target ads. Health and calendar data is used to produce your score, your recovery read, and your plan, and nothing else. The full detail is in the Privacy Policy.

Your Hybrid Score is free, forever, with no card. Pro adds Atlas and the planner that rewrites your week, as a subscription bought in the app through the App Store; current prices are on the pricing page. Cancel any time in your iPhone settings, under your Apple ID and Subscriptions.