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There are all kinds of different apps on the market today that can help you improve your health and perform health tracking activities. One of the most popular are apps that are supposed to track and record your heart rate. This is an important health measurement, so it seems as if this would be a good way to start monitoring your health, but in reality these kinds of apps aren’t as good as advertised.
Heart Rate vs Pulse Rate
Most of the time, people use the words heart rate and pulse rate interchangeably when in fact they aren’t exactly the same thing. Your heart rate is the number of times your heart contracts each minute to push the blood through your body. Your pulse rate on the other hand is the pulse of the blood as it moves through the capillaries in your body. These two measurements are closely related, the pulse rate is caused by the heart contractions after all, so most of the time these measurements can be used interchangeably.
However, when there’s a serious problem with your heart, confusing these measurements can be extremely dangerous and give you a false idea of your condition. And the frightening thing is, the worse the problem with your heart, the bigger the app accuracy problem is. The only way to get a clear and accurate idea of your heart rate is with an ECG, so it’s important that you not use your phone app as your sole health monitoring measure.
How Heart Rate Apps Work
Every time your heart beats, blood is sent through the capillaries in your body. The app on your phone can detect this rush of blood through a process called photo plethysmography. As the camera flash illuminates your skin, the camera picks up the color changes that occur every time the blood pulses. This results in what’s called a pulse wave and is the first stage of the process. The heart rate app than analyzes the pulse wave to find the maximums and other important points in the wave, which are used to determine where the heart beats start and end. This is the second stage of the process. In the third stage, the app calculates the rate of beats per minute.
Problems with the Measurement Process
This process for measuring pulse rate can present a number of problems. Firstly, it can be difficult to find the best place to measure the heartbeat. Usually this will be the finger or a wrist, but both areas can present problems for heart rate measurement. How to take the measurements is also an issue. The most efficient and accurate way to measure is for the camera light to penetrate through the tissue, but this doesn’t work on the wrist as it’s too thick. It does work very well on the finger, which is thin enough that the light can penetrate through to the other side. The other method, where the light reflects from the tissue, is much less accurate even though this method is usually used with watch style health monitoring devices.
In the second stage, where the app uses the maximums to determine the heart rate, there are some serious errors that can occur. The shape of the pulse wave that results from the camera flash is determined by external and internal factors. So it can be very hard to determine if the maximums are caused by the heartbeat, or by something completely unrelated. And because the algorithms used to measure and analyze the pulse wave are kept secret, there’s no way to determine if these kinds of health measurements are appropriate or even helpful in specific critical situations.
After completing all of these calculations, heart rate apps use the information to calculate the pulse rate. This final stage is less problematic than the others, but can still cause errors. Because of the instability of the pulse wave that results from stage one, the program doesn’t always properly recognize how long each heart beat takes. And when this occurs, the interval it uses to calculate the rate per minute is too short, resulting in incorrect calculations.
Implications of the Study
Health monitoring is a great way to get a deeper understanding of your personal health, and to track changes that could indicate potential problems. Using tools such as apps can be extremely helpful in this process, but the limitations of the tools need to be acknowledged. There is no app, tool or program that can replace a health assessment performed by a trained physician, and the information you gather through these sources should only be used to support and help your doctor, not replace them altogether.
Tags: health tracking, health monitoring, personal health, health assessment
