Your Rhythm Studio — Help & Reference

1. Heart Rate Variability (HRV) — Science

Heart Rate Variability is the variation in time between consecutive heartbeats. Despite the name suggesting "variability is bad," the opposite is true: higher HRV generally indicates a healthier, more adaptable autonomic nervous system (ANS).

The Autonomic Nervous System and the Heart

Your heart rate is constantly modulated by two opposing branches of the ANS:

• Sympathetic ("fight or flight") — speeds the heart, suppresses HRV. Activated by stress, exercise, fear.
• Parasympathetic ("rest and digest") — slows the heart, increases HRV. Dominant during sleep and recovery.

HRV is the net result of this push-pull balance. When parasympathetic activity is high (you are calm, rested, recovered), the intervals between heartbeats vary more — a sign the brain is actively fine-tuning cardiac output. When sympathetic activity dominates (exercise, stress, illness), intervals become more uniform and HRV falls.

What RMSSD Measures

This dashboard uses RMSSD (Root Mean Square of Successive Differences) as the primary HRV metric. It is the most clinically validated short-term HRV measure and is especially sensitive to parasympathetic tone.

Where RR is the time in milliseconds between consecutive R-peaks (heartbeats), and N is the number of successive differences in the window.

RMSSD Range	Interpretation	Typical Context
< 15 ms	Very Low	High stress / illness / exercise peak
15–30 ms	Low	Moderate stress / light activity
30–60 ms	Normal	Healthy resting adult
60–100 ms	Good	Well-recovered / high fitness
> 100 ms	Excellent	Athletes, deep sleep, vagal dominance

2. How We Process & Display HRV

Data Source

HRV is now provided as a single measured value from the Measured HRV metadata field in your CSV file. This represents a gold-standard measurement taken under controlled conditions, typically during a 2-minute resting measurement protocol.

Single Value Display

Instead of calculating HRV trends from the RR intervals during activity (which can be unreliable), the dashboard now displays the measured HRV as a single value with color-coded status indicators:

HRV Range (RMSSD)	Status	Color	Interpretation
< 15 ms	Very Low	Red	High stress / illness / exercise recovery
15–30 ms	Low	Orange	Moderate stress / light activity recovery
30–60 ms	Normal	Green	Healthy resting adult baseline
60–100 ms	Good	Cyan	Well-recovered / good fitness level
> 100 ms	Excellent	Purple	Athletic level / deep recovery

Why Single Values?

HRV is not a valid measure during physical activity, stress, or arrhythmias. By using a single measured value taken under standardized conditions, we ensure the HRV reading reflects true autonomic nervous system function rather than artifacts from movement or exercise.

3. Resting Heart Rate (RHR)

Resting Heart Rate is also provided as a single measured value from the Resting HR metadata field in your CSV file. This measurement is typically taken under the same controlled conditions as the HRV measurement.

RHR Status Indicators

RHR Range	Status	Color	Interpretation
< 50 bpm	Low	Orange	Very fit or possible bradycardia
50–60 bpm	Good	Green	Excellent cardiovascular fitness
60–80 bpm	Normal	Blue	Normal resting range
80–100 bpm	Elevated	Orange	May indicate stress or poor recovery
> 100 bpm	High	Red	Possible health concern

4. ECG Chart — Reading the Display

Trace Colours by Rhythm

Colour	Label	Meaning
■	Normal	Normal sinus rhythm
■	AFIB	Atrial fibrillation — irregular R-R, absent P-waves
■	SVT	Supraventricular tachycardia
■	VT	Ventricular tachycardia
■	PVC	Premature ventricular contraction — wide bizarre beat
■	PAC	Premature atrial contraction — early narrow beat

Overview Envelope

When viewing a full session or a 10-minute segment at full zoom-out, the chart switches from individual samples to an envelope view — a shaded band showing the signal's min/max range per time bin. This preserves performance for long recordings while still showing overall signal quality and events.

The envelope automatically switches back to individual ECG samples when you zoom in to less than ~2 minutes of data.

5. Event Navigation

The Event Navigation Bar appears at the right side of the segment toolbar. Each button corresponds to a detected or user-marked event in the session.

• Click once — Jumps to the first occurrence and zooms in to ~10 seconds of ECG
• Click again — Cycles to the next occurrence of the same event type
• After the last occurrence it wraps back to the first

6. Heart Rate Zones

Zone	Name	% Max HR	Purpose
Z1	Recovery	50–60%	Warm-up, cool-down, active rest
Z2	Base / Aerobic	60–70%	Fat oxidation, aerobic base building
Z3	Tempo	70–80%	Aerobic capacity, lactate threshold
Z4	Threshold	80–90%	Lactate threshold improvement
Z5	Max / VO2max	90–100%	Speed, power, VO2max

Toggle the Zone button in the viz-bar to show the coloured zone band beneath the ECG. Zone data is sourced from the zone column in your CSV.

7. Activity Tracking

Activity labels are sourced from the activity column in your recording CSV. Common values include: resting, walking, running, exercise, sleeping, driving, cooldown.

Activity regions appear as labelled, coloured panels in the Activity bar at the bottom of the chart. Toggle with the Activity button in the viz-bar.

Activity context is also used internally by the HRV engine — periods labelled with vigorous exercise will be classified as Active in the HRV trend even if the accelerometer is quiet (e.g., cycling).

8. Getting Sessions from Phone to Dashboard

There are two ways to get your recorded sessions from the ItHeartBeats phone app into the Cardio Dashboard for analysis: Wi-Fi Sync (recommended) and USB Cable (fallback).

Quick Comparison

Method	Ease	Speed	Requirements
Wi-Fi Sync	Easiest — tap and go	Instant over local network	Phone & PC on same Wi-Fi
USB Cable	Simple — pick a file	As fast as file copy	USB cable, phone unlocked

Method 1: Wi-Fi Sync (Recommended)

The phone runs a small background server that lets the Cardio Dashboard discover it on your home network and download sessions automatically. No accounts, no cloud, no configuration files.

On the Phone App

1. Open ItHeartBeats — the Wi-Fi server starts automatically when the app launches.
2. Go to Settings — scroll to the WI-FI SYNC card.
3. Check the IP address — it will show something like http://192.168.1.120:8080
4. That's it! — you don't need to do anything else on the phone. Keep the app open.

On the Cardio Dashboard

1. Open the Data panel in the left sidebar.
2. Look for "Phone (Wi-Fi)" — this is the connection section.
3. Connect:
   • Auto-discover: Click Quick Scan — the dashboard will search your network and find the phone automatically.
   • Manual: Type the IP address shown on your phone (e.g., 192.168.1.120) into the IP field and click Connect.
4. Done! — The status line turns green and shows your phone model + how many sessions are available.

First-Time Setup Options

Setting	What It Does	Recommended
Auto-Connect	Automatically reconnects to your phone when you open the dashboard	ON
Auto-Sync	Automatically downloads new sessions in the background	ON
Auto-Discover	Scans the network for your phone if the saved IP doesn't respond	ON

Method 2: USB Cable (Fallback)

If Wi-Fi isn't available or you prefer a wired connection, you can simply plug in your phone and load the CSV file directly.

On the Phone

1. Connect your phone to the PC with a USB cable.
2. Unlock the phone and allow file access if prompted.
3. Automatic sync: The app will automatically copy sessions to Documents/YourRhythm-Data when USB is connected
4. Or export manually: Go to History → tap a session → Export

On the Cardio Dashboard

1. Copy files to PC first: In Windows Explorer, copy CSV files from your phone's Documents/YourRhythm-Data to C:\YourRhythm-Data on your PC
2. Click the "Open Folder" button in the Data panel (select "Open Folder" from Source dropdown).
3. Navigate to C:\YourRhythm-Data
4. The dashboard will automatically import all CSV files from that folder.

Understanding the CSV File

Each exported session contains multiple sections with all your recording data:

Section	Contains
[SECTION:METADATA]	Session info: date, duration, device, patient ID, Resting HR, Measured HRV, sample rate
[SECTION:EVENTS]	All detected cardiac events with timestamps, types, feelings, and RR intervals
[SECTION:EVENT_WINDOWS]	Compact ECG strips around each event (for quick review without full raw data)
[SECTION:RAW_ECG]	Full raw recording: ECG signal, BPM, RR intervals, accelerometer, event markers

Resting Heart Rate & HRV in Exports

When you perform an "HRV & RHR" measurement session on the phone, the resulting values are embedded in every subsequent export:

• Resting HR (bpm) — Your baseline resting heart rate, used for Karvonen zone calculations.
• Measured HRV (ms) — Your RMSSD value from the 2-minute measurement protocol.

The Cardio Dashboard reads these automatically and displays them in the Settings panel under Physiology. The status indicators show:

Colour	RHR Meaning	HRV Meaning
Green	<60 bpm — Athletic	>50 ms — Excellent
Blue	60-72 bpm — Good	30-50 ms — Good
Amber	73-80 bpm — Average	20-30 ms — Fair
Red	>80 bpm — Elevated	<20 ms — Low

Troubleshooting

Problem	Cause	Solution
"Connection Failed"	Phone and PC not on same network	Check both are on the same Wi-Fi (not mobile data, not guest network)
"No Sessions Found"	No exported CSVs on phone	Record a session and export it first, or check Documents/YourRhythm-Data folder exists
"No Wi-Fi connection" on phone	Phone on mobile data only	Connect phone to Wi-Fi. The server needs a local network to work.
Phone IP keeps changing	Router assigns dynamic IPs	Use Quick Scan to find the new IP, or set a static IP on your phone/router
Scan finds nothing	Network blocks device-to-device traffic	Some corporate/guest Wi-Fi blocks this. Use your home network or USB instead.
USB: phone not showing files	Phone locked or USB mode wrong	Unlock phone. In the USB notification, select "File Transfer / MTP" (not just charging)
CSV loads but shows no data	File may be an older format	Re-export the session from the phone app to get the latest format

Folder Organization (Wi-Fi Downloads)

When sessions are downloaded via Wi-Fi, they can be automatically organized into folders:

• Flat — All files in one folder (simplest)
• Daily — Grouped by date (e.g., 2026-04-11/IPM-26.04.11.csv)
• Monthly — Grouped by month (e.g., 2026-04/IPM-26.04.11.csv)
• Yearly — Grouped by year (e.g., 2026/IPM-26.04.11.csv)
• Custom Pattern — Use variables to create your own structure

9. Exporting from Dashboard

The Cardio Dashboard provides two export options in the Export sidebar panel for clinical reporting and basic data export.

Export as PDF (Clinical Report)

Generates a structured clinical report as a PDF document with three sections:

• Section 1: Session Information — Session name, date, duration, sample rate, number of events, patient ID
• Section 2: Clinical Findings Summary — Narrative summary from the dashboard Session Summary panel, showing detected arrhythmias and rhythm analysis
• Section 3: ECG Event Segments — ECG waveform strips (±5 seconds) around each detected event, with event type, timestamp, and RR interval

Export Raw CSV Data

Downloads basic session metadata as a simple CSV file. Contains:

• Session name
• Date
• Duration (minutes)
• Sample rate (Hz)
• Patient ID (if available)
• Device (if available)
• Start time (if available)

Append to Trends Log

Available in the Trends tab, this option appends the current session's key metrics to a trends CSV file for longitudinal tracking. Includes:

• Session identity (ID, date, duration)
• Heart rate statistics (min, max, average, range)
• HRV metrics (RMSSD, SDNN, PNN50, SD1, SD2)
• Rhythm event counts (PVC, PAC, AFIB, etc.)
• Zone minutes (Z1-Z5)
• Sleep metrics (if available)
• Respiratory rate (if available)

10. UI Controls Reference

Segment Bar (top of chart)

Control	Action
All	Show full session overview (envelope mode)
00:00 10:00 …	Jump to a 10-minute segment and show detailed ECG
Coloured event buttons	Cycle through all occurrences of that event type
↺ RESET	Reset zoom to the current segment default
AUTO-Y	When checked, auto-scales the Y-axis to the visible ECG signal amplitude

Viz Bar (bottom of chart)

Toggle	What it shows
ECG	The raw ECG waveform (rhythm traces)
BPM	Smoothed heart rate trend line (red, right axis)
HRV	Rolling RMSSD trend — green = valid, orange dashed = unreliable
Motion	Accelerometer ENMO (movement intensity)
Events	Arrhythmia highlight overlays and symptom markers
Activity	Activity label bands
Zone	HR zone coloured bar
Compact	Stack all panels vertically (split layout)
Smooth	Apply digital smoothing to the ECG waveform
FONT A a	Increase / decrease global text size

11. Contact

For questions, support, or feedback, please contact us at: YourRhythm101@gmail.com

Visit our website at YourRhythm.co.uk