When choosing a ring size, finger selection is important. We tend to see the
strongest signal strength from the index finger, but the middle, ring, and
pinky fingers can also have strong signal strength. Some factors to consider
when thinking about finger selection are:
The development of capillaries, which deliver blood, is influenced by use of
the finger. Just like other areas of the body, the more the area is used the
denser the capillaries. So, the more widely used fingers are likely to have
greater blood flow, yielding stronger signal strength.
Bone structure, specifically knuckles, can impact performance. A snug fit
must be accomplished while retaining the ability to remove and replace the
ring. A finger with a knuckle much larger than the circumference of the
finger should be avoided.
Factors that can impair signal quality
For certain exercises, such as weightlifting, it may be difficult to auto-detect
Active Minutes. This is because when you’re lifting heavy weights for an
extended period of time or gripping something tightly, it’s more difficult for
the heart rate sensor to get a clear reading. This is consistent with all optical
sensors, which is why wrist-based devices have the same problem.
The sensor can accommodate for movement related to locomotion, like arms
pumping while running, but cannot adjust for movement of the tissue under
the sensor, like flexing or moving the muscles of the fingers. This means that
disturbances and pressure changes, such as dribbling a basketball, punching,
or tightly gripping handlebars, could impact signal possibly beyond our
ability to correct.
Another factor that can impair signal quality is temperature, as in cold
weather blood can retreat from your fingers, which can also make it difficult
for the heart rate sensor to get a clear reading.
Optimizations
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