Biostrap, a screenless PPG wristband for health data
Heart rate, HRV, respiration and oxygen, but only at rest.
- Answers
- What does the Biostrap wristband actually measure?
- Topics
- data · design · experiment · health · heart · lifestyle · review · sensors · sport · watch
- Full article on willem.com
- https://willem.com/en/2017-11-15_collecting-health-data-with-biostrap/
Summary
When I wore Biostrap for a month in 2017, its wrist PPG sensor recorded heart rate, heart rate variability, respiratory rate and blood oxygen saturation, but only while at rest, roughly every ten minutes.
Full text
Biostrap is deliberately minimal: no screen, no buttons, no buzzing, just a rubber strap holding a sensor. Two red LEDs illuminate the blood in your wrist and the sensor captures the reflected light as a waveform. Roughly every ten minutes it attempts a recording, and anything taken while moving is discarded. Cloud services analyse every beat on 29 parameters; a good day yields about 2000 beats. A gyroscope adds movement data, and combined with the PPG readings this gives a comprehensive sleep analysis. An optional shoe pod helps recognise activities. The main limitation is that it does not know your heart rate during exercise, which biases daily averages, but the app exports automatically to Apple HealthKit, where I merge it with data from other sensors. Battery life was about 4 days, charging from 0 to 60% in under an hour.