Smartwatches A universe of health metrics, trackers, and scams

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AMMAN — Today, technology has seen its way into every facet of our lives, and fitness is no exception. With the development of smartwatches, it has never been easier to collect data on vitals and other health metrics. But many consumers do not know where to start when it comes to these devices. Which is better? Which has the best capabilities? Which is more useful?اضافة اعلان

Understanding the technology behind these smartwatches can help buyers make informed decisions while shopping for these devices. 

Heart rate

Heart rate is the measurement of how many times your heart beats within a specific amount of time. The universally used metric is beats per minute (bpm). The normal range for heart rate at rest should be between 60-100bpm but can vary between individuals. A lower resting heart rate is indicative of more efficient blood pumping and stronger cardiovascular health. A well-trained athlete can have a resting heart rate as low as 40bpm.

Measuring heart rate during fitness is a useful guide to assess your intensity of workout. There are simple calculations that can be done to figure out at what intensity you should be working at. First start by taking your age and subtract 220 by it. This number is your estimated maximum age-related heart rate. For example, if you are 25, you estimated maximum heart rate would be 195 bpm.

After calculating your estimated maximum heart rate, you can use it to find a range that reflects intensity levels of workouts. According to the American Heart Association (AHA), moderate intensity workouts should be 50-70% of your maximum heart rate and high intensity should be 70-85% of your maximum heart rate. Using the previous example, this would mean that moderate exercise for a 25-year-old should fall in the range of 98 – 137 bmp and high intensity should be between 137 – 166 bmp. These ranges do not have to be strictly adhered to but do serve as a good reference range.

Heart rate variability (HRV)

HRV is the measurement of the variation of time between heartbeats. The variation of time between beats is not controlled consciously and is instead the responsibility of the autonomic nervous system (ANS). When stress levels are high or physical exertion is involved, the variability between beats are low, and when at rest, the variability is high. Therefore, having a high HRV at rest is indicative of higher cardiovascular fitness and stress resilience.

HRV is a useful tool in stress management but can also be useful in gauging any ANS imbalances, especially during exercise (where the HRV should be low when compared to at rest). Reading raw data from HRV can be complex, but smartwatches tend to disseminate information into useful feedback on a person’s emotional state.

Electrocardiogram (ECG or EKG)

This is by far the most exciting aspect of smartwatches and is a testament to how far technology has advanced for mankind. An ECG is used to check the heart’s rhythm and electrical activity and identify atrial fibrillation (Afib). The ECG is a powerful piece of technology that can measure and detect electrical impulses generated by the heart through the surface of the skin.

The traditional 12-lead ECG requires the placement of 10 pads in specific areas of the torso. Smartwatches have developed a new form of ECG called the single-lead ECG (iECG). It measures electrical impulses through two contacts, one on the back of the watch on the wrist and through the fingertip of the other hand placed on the screen. This technology is still in its infancy, but despite this, one study found that when compared to a 12-lead ECG, the iECG had “moderate diagnostic accuracy.” The technology is not able to classify other types of arrythmias (abnormal heart rhythms) and should not be used for self-diagnostics, even in Afib.

Oxygen saturation (O2 Sats)

O2 Sats is the measurement of oxygen in the blood. A normal range, especially at rest, should be between 95-100 percent. Any reading below 90 percent may require a trip to the hospital. Your O2 Sats depend on different factors, such as that amount of oxygen breathed in, the efficiency of gas exchange in the lung (oxygen in and carbon dioxide out), hemoglobin count (the cells responsible for oxygen transport), and hemoglobin affinity (how well oxygen binds to it). Having a device to measure your O2 Sats can be useful during exercise as it can serve as a metric to measure your breathing technique.

If you practice poor breathing techniques, especially during high intensity exercise, it would be reflected in a lower-than-normal O2 Sat. Generally, the oxygen level should not decrease, even during strenuous activity as it is compensated by an increase in respiratory rate. Exercising with low O2 may transition the body from aerobic metabolism (with oxygen) to anaerobic metabolism (without exercise), which can increase lactic acid production, resulting in muscle soreness and potentially metabolic acidosis (acidic bodily fluids).

Sleep tracking

Sleep is as crucial to fitness as it is to general health. After high impact exercise, such as running, your body accumulates micro tears and fractures in the muscles and bones. Sleep recovers and repairs any damages sustained throughout the day. Additionally, it is integral to cognitive function.

It is divided into four different stages (Stages 1-4) and two broad categories. The two categories are REM (Rapid Eye Movement) and NREM (non-Rapid Eye Movement) sleep. REM is considered the most important aspect of sleep for cognitive function and is when dreaming occurs. Between the stages, there are differences in breathing and heart rate that these smartwatches can pick up and track to assess the quality of sleep over time and establish a healthy sleep cycle.

Blood pressure and blood glucose

Blood pressure is the measurement of pressure produced by the heart. The normal range for blood pressure should be less than 120/80 mmHg and is a good indicator for heart complications and diseases. Unfortunately, the technology to measure blood pressure is not quite there yet. Similarly, there are no devices capable of measuring blood glucose.

Which to get?

The question of what device to purchase is based on based on personal preference. If you are a fitness junkie, smartwatches like the Fitbit can measure key metrics for fitness and link through a smartphone app. If you prefer ergonomics, utility, and user-friendly devices, Apple Watch or Samsung Watch are also viable options. The most important thing is to do your own research, make informed decisions based on your personal needs, and beware of scammers.

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