Why ZenMonkey Adds HRV and Resting Heart Rate: Another Perspective on Your Practice
After a session, ZenMonkey invites you to save how calm you feel and a personal note. Those reflections come from you, and they remain an important part of your practice history.
Some questions are easier to consider over time. Have you been practicing more regularly? Did your routine change? Does a measurement reflect one unusual day or a longer pattern?
Version 1.5.0 adds HRV and resting heart rate to give that review another perspective. The timer, history and reflections remain. Members who choose to connect Apple Health can place existing body measurements alongside their practice records.
Different measurements, different perspectives
Heart rate variability describes variation in the intervals between heartbeats. ZenMonkey reads Apple Health's SDNN measurement in milliseconds. It is different from beats per minute and is not a direct reading of psychological stress. Apple's HRV data type
Resting heart rate is a separate measure. ZenMonkey reads existing resting heart rate records from Apple Health and summarizes them by day; it does not substitute your average session heart rate. Its history can show changes without explaining their cause. Apple's resting heart rate data type
Sleep, exercise, health, measurement time and device source can affect these records. The comparison is with your own history in a comparable context, not a ranking against other people.
A state, without a health grade
The awareness ring shows Lighter, Usual or Elevated, without a numeric health score. These are reference states relative to personal HRV history, not grades for your health, feelings or meditation.
The reference needs at least seven comparable historical days within the previous 28 days. Measurements are matched by source, day or night context and duration, with known practice-adjacent measurements excluded. Without enough data, the app explains that it is still building a reference.
Older measurements remain visible with their actual time. After one hour, they are a previous reference, not a current assessment, and cannot trigger a current practice invitation. Refresh reads existing Health data; it cannot force a new HRV measurement from Apple Watch.
There is a reason to keep this boundary clear. A real-world longitudinal study found a limited relationship between wearable-derived HRV and perceived stress. HRV alone is not enough to determine how stressed someone feels. ZenMonkey's reference method is a product design, not a clinically validated stress diagnosis. Read the study
Trends that leave missing days empty
The dedicated Trends tab separates Practice Trends from Body & Mind Trends. Both offer 7, 30, 90 and 180 days, and one year.
HRV and resting heart rate change cards include bars with a dashed reference. That line is the median of complete measured days in the selected period, excluding today, with at least two days required. This period reference differs from the ring's 28-day personal reference: one describes the selected dates; the other compares the latest measurement with its history.
HRV bars above the period reference are colored. Resting heart rate bars below it are colored. Equal values, the other direction and unavailable references are gray. Color describes relative position, not a diagnosis. Missing dates stay empty; no zeros or invented curves fill the gaps.
Practice is part of the context
Body & Mind Trends also displays practice records. With sufficient data, it can compare next-day measurements after days with and without a recorded practice.
That is a descriptive association. An unrecorded day does not mean no practice happened. The comparison does not control sleep, exercise, illness or device changes. A change alongside practice does not prove that practice caused it, and it is not a score for an individual session.
The records can help you ask better questions: What else changed in your routine? Is the measurement history consistent? Does it match how you felt? They need not provide the final answer.
Easier to glance at, optional to be reminded
Home Screen widgets can show an existing HRV reference, measurement time and history. Watch-face widgets offer a glanceable reference and open practice when tapped. The monkey practice shortcut remains free; HRV awareness and Body & Mind Trends require membership. Resting heart rate history is available in the iPhone and iPad trends view.
HRV awareness reminders are off by default. If you enable them, sufficient personal history and fresh, sustained changes may prompt a gentle invitation to practice. Time windows, cooldowns and system background scheduling still apply. This is not continuous monitoring, an alarm or an emergency service.
Start with what you choose to enable
In version 1.5.0 or later:
- Open Settings → Data & Sync → HRV Body & Mind Awareness to review the membership feature and choose whether to enable it, then manage Health reading permissions.
- Enable resting heart rate reading in the app's Apple Health settings if you want that history.
- Visit Trends → Body & Mind Trends. Widget previews and all setup steps share one sheet in Settings → Home Screen Widgets.
Writing mindful minutes, saving Watch workouts and reading Health data are separate choices. You can continue with only the timer and reflections. Turning off writes does not delete existing Health records. Raw HRV and resting heart rate histories are not sent to our analytics service.
ZenMonkey remains a tool for your own practice. These additions bring more context to reflection while leaving you in control of what to view and whether to receive reminders.
See Support for setup and missing-data questions, and the Privacy Policy for data handling.