Marcwills HRVA

MARCWILLS HRVA turns an Android phone and a Polar H10 chest strap into a portable heart rate variability (HRV) lab. It is built for people who need HRV data they can trust and analyse later: sport science researchers, exercise physiologists, coaches, lecturers and students. WHAT IT DOES HRVA connects to the Polar H10 over Bluetooth and records heart rate, every beat-to-beat (RR) interval, the ECG signal and chest movement at the same time. While you record, it calculates HRV live and tells you whether each value is already reliable. After the session, it gives you a report and clean data files for your own analysis. WHY RESEARCHERS USE IT Know when your numbers are valid. Every HRV variable is checked minute by minute against three conditions: enough recording time for that measure, a low share of artifact beats, and a still participant. Each value is marked valid or not yet valid, on screen and in the exported data, so you do not report a number that was computed on too little or too noisy data. Follow established methods. Time-domain measures use 60-second and 300-second windows in line with the Task Force 1996 HRV standards. Each session includes a methods file describing how the values were calculated, ready for your methods section. Keep your protocol on the timeline. During a recording you can mark numbered events with a short note, record changes in body position, and open or close analysis windows. Every marker is saved with both elapsed time and clock time, so you can line up the data with your protocol afterwards. Work with many participants. A participant registry stores each person under a study code, with the name optional, which supports anonymized research. Age, gender and an optional athlete or sedentary label are recorded, and past sessions can be reopened at any time. Take your data anywhere. Raw RR intervals are exported as a plain text file with one value per line, which common HRV analysis software can import. You also get per-minute HRV values with their validity flags, heart rate, accelerometer data and your session markers as CSV files, plus a PDF session report. TWO RECORDING MODES Stationary Mode is for resting measurements. It shows RMSSD, ln RMSSD, SDNN, pNN50 and Mean RR; SD1, SD2 and SD1/SD2 with a live Poincaré plot; and LF, HF, LF/HF and Total Power from a Welch power spectrum. Activity Mode is for training. It shows heart rate as a percentage of heart rate reserve (Karvonen method) against ACSM or AHA intensity zones, tracks time in each zone, and can alert the participant by vibration or sound when they leave the target range. ALSO INCLUDED A live ECG waveform at 130 Hz for checking electrode contact and signal quality. A motion indicator that shows whether the participant is still. The live battery level of the sensor. A choice of export routes: the Android share sheet, automatic copies to a folder you choose, or a full database backup. PRIVATE BY DESIGN HRVA has no account, no advertising and no internet access. Recordings stay on your device and are never sent to the developer or to anyone else. Data leaves the app only when you export it yourself. This helps you meet ethics-committee data-protection requirements. REQUIREMENTS Android 11 or later with Bluetooth, and a Polar H10 chest strap (sold separately). MARCWILLS HRVA is an independent app and is not affiliated with Polar Electro Oy. IMPORTANT MARCWILLS HRVA is for research, education and wellness use. It is not a medical device and must not be used to diagnose or treat any condition. The ECG display is for checking signal quality and does not replace a medical ECG; if anything during a recording concerns your health, see a doctor. In Activity Mode, the person who plans and runs the exercise is responsible for screening and supervising participants. ABOUT MARCWILLS HRVA is the first app of the MARCWILLS physiological monitoring platform, developed by Kukuh Pambuka Putra, sport scientist and exercise physiologist.