OH1 does not detect my heart rate, what can I do?
To maintain the best possible performance of the optical heart rate measurement, keep your OH1 clean and prevent scratches. The measurement is based on tiny changes in light intensity, and even a small amount of dirt on the sensor at the back of the device can reduce its performance. Similarly, scratches on the sensor can scatter the light from the LEDs into unwanted directions and weaken the device’s performance.
Movement between the OH1 and your skin can interfere with the readings. That is why it’s important that you wear the armband snugly on around your forearm or upper arm, not around your wrist. Try out different locations on your forearm or upper arm to find a location that consistently finds your heart rate. The OH1 must be touching your skin but not so tightly that it prevents circulation or feels uncomfortable.
Activities that involve irregular hand movements, such as racket sports, make it harder to get an accurate heart rate reading from your arm. When playing these sports, you can switch the handedness of the OH1 and change it to the non-hitting hand. If you perform activities that cause extreme pressure on your arms, such as weightlifting or pull-ups, your heart rate may be more difficult to detect from the arm.
In cold conditions, blood circulation on the skin may become too weak for the sensor to get a proper reading. You can solve this by warming the skin on your arm or by doing some exercise to increase skin temperature.
