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Hey guys @Invader75 and @SunsetRunner, it's nice to see you around the Community Forums! As you may know, your heart rate may be affected by any a number of factors at any given moment. Movement, temperature, humidity, stress level, physical body position, caffeine intake, and medication use are just a few things that can affect your heart rate. Different medical conditions and medications can impact your heart rate as well.
When your heart beats, your capillaries expand and contract based on blood volume changes. PurePulse LED lights on your device reflect onto the skin to detect blood volume changes and finely tuned algorithms are applied to measure heart rate automatically and continuously. The heart-rate icon you see on the display tells you if you're in 1 of 3 heart-rate zones.
Resting heart rate refers to the heart rate measured when you’re awake, calm, comfortable, and have not recently exerted yourself. We use your heart rate data from when you’re awake and asleep to estimate your resting heart rate. For best accuracy, wear your device to sleep.
Your resting heart rate is usually higher than your heart rate while you are asleep, so don’t be surprised if your resting heart rate is higher than the lowest number that you see in your heart rate graphs.
Your tracker can have difficulty finding a signal, typically due to the tracker's fit. For example, wearing your band tightly may constrict blood flow in your wrist and affect the signal. We recommend experimenting with how high you place the tracker on your wrist. When you're not exercising, wearing the tracker just above the wrist bone--as you would a watch--typically works fine. However, moving the tracker up a couple inches can be helpful during high-intensity exercises or exercises that cause you to bend your wrist frequently. If you haven't already done so, please review our recommendations for wear and other tips shared by @SantiFitbit.
Note that on Fitbit Ionic, the heart-rate value appears gray if your watch is searching for a stronger reading.
Were you holding onto the treadmill side rails? If so, the tracker cannot detect your number of steps since your arm is not moving. If you walk with a normal arm swing on the treadmill, it should count the proper number of steps and calories.
Also, remember that if you are using the Treadmill exercise mode on the Fitbit it will use the Walking Stride Length and not the Running Stride Length for calculating distance from the number of steps. This will cause the distance to be off substantially. So, if you are running on the treadmill, it is better to use the Run exercise mode, assuming you have correctly set up the stride lengths for Walk and Run. But, it is important that your arms swing freely in order for the Fitbit to count steps, and not held next to the body.
Try the recommendations and let me know the outcome!
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