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Hi there @NFitz. Great to see you in the Community Forums! 🙂
As you mention, it's super important for your tracker to fit a little tight while you're working out to pick up an optimal heart rate and therefore, count your activity more accurately.
For all-day wear when you’re not exercising, your tracker should usually rest a finger’s width below your wrist bone and lay flat, just as you would wear a watch. Fitbit’s PurePulse heart rate tracking system is designed to be most accurate when the tracker is worn on the top of your wrist.
For improved heart rate accuracy keep these tips in mind:
- 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 inches can improve the heart rate signal. Also, many exercises such as push-ups 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.
- 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.
- With high-intensity interval training, P90X, boxing, or other activities where your wrist is moving vigorously and non-rhythmically, the movement may prevent the sensor from finding an accurate heart rate. Similarly, with exercises such as weight lifting or rowing, your wrist muscles may flex in such a way that the band tightens and loosens during exercise. Try relaxing your wrist and staying still briefly (about 10 seconds), after which you should see an accurate heart rate reading. Note that your tracker will still provide accurate calorie burn readings during these types of exercise by analyzing your heart rate trends over the course of the workout.
If you'd prefer, you can also buy smaller wrist bands only since they are interchangeable as you may know. You can find them available on the online store.
Anything else you might need help with, let me know. I'll be happy to help! 🙂
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