Letscom ID131Color HR User Manual page 7

For optimized heart rate tracking, keep these tips in mind:
1. Experiment with wearing the tracker higher on your
wrist during exercise. Because blood flow in your arm
increases the farther up you go, moving the tracker up
a couple of inches can improve the heart rate signal.
Also, many exercises such as bike riding or weight
lifting cause you to bend your wrist frequently, which is
more likely to interfere with the heart rate signal if the
tracker is lower on your wrist.
2. Do not wear your tracker too tight; a tight band restricts
blood flow, potentially affecting the heart rate signal. That
being said, the tracker should also be slightly tighter (snug
but not constricting) during exercise than during all-day
wear.
- 4 -