4Frequently asked
Before you start
- Do I really need a chest strap?
- Not for the pacer and the sound, and that is the part you use daily. For anything measured, yes: finding your resonance rate and getting readings needs beat intervals.
- Will my strap work?
- Any Bluetooth heart rate monitor that transmits beat-to-beat intervals. Tested with the Polar H10. Also suitable: Polar H9, Wahoo Tickr, Garmin HRM, Coospo H6 and H808S.
- Does it work with an Apple Watch?
- Not for training. The watch does not hand continuous beat intervals to a third-party app, and optical sensors at the wrist are less accurate than a chest strap under slow breathing.
- How long is a session?
- Ten minutes is usual, five is complete. The workshop that finds your rate takes 15 to 19 minutes, once.
Using it
- It makes me dizzy.
- Then you are breathing too deeply. Correctly performed slow breathing raises your CO2, it does not lower it. Dizziness is a technique fault rather than a property of the exercise: smaller, calmer breaths, and the tone still carries you.
- It feels effortful, not calming.
- That is common in the first weeks and not a sign you are doing it wrong. In one study the measured variability rose as expected, and perceived stress rose with it. Smaller breaths help, and so does time.
- Why are my numbers different from other apps?
- Because most measure at rest and 4-6 measures during guided slow breathing, which lifts variability substantially. Compare with your own earlier sessions rather than with resting values or population tables.
- Why does it refuse to grade some figures?
- Because a grade would mislead. LF/HF is not a stress ratio when the breathing itself sits in the LF band. SDNN reference values come from 24 hour recordings. The app shows the figure and says why it will not rate it.
Money
- What does it cost?
- Starting costs nothing, and the pacer, the sound and the workshop stay free forever. Anyone who keeps at it for weeks is asked about a subscription. Access to the app remains either way; the written coaching and the trends move behind it.
- Refunds
- Apple handles purchases and subscriptions, and therefore refunds: reportaproblem.apple.com. Write to us anyway if something did not work.
Data
- Where does my data live?
- On your iPhone. Details in the privacy policy.
- What do you write to Apple Health?
- Mindful minutes from every session, and SDNN only if you allow it. The caveat belongs with it: paced breathing lifts SDNN, so the figure can shift your baseline in other apps.
Is this a medical device?
No. 4-6 is a training and measurement tool. It diagnoses nothing, treats nothing, and does not replace medical advice. Health questions belong with a doctor.
Still stuck?
Write to [email protected]. A person answers, usually within two working days.