Consumer grade activity trackers have been steadily increasing in popularity in recent years. Although these wearables initially were very unreliable, today they are more accurate than ever before. For example, the newest Apple watch is considered a medical device and has been approved by the FDA. Apple's is the first ever smartwatch to receive FDA clearance for EKG monitoring. At first, these devices were exclusively used in medical settings or by elite athletes. Today, consumers range from beginner exercisers to those looking to share heart data with medical professionals. This FDA approval is fantastic news for cardiac patients who are increasingly likely to track and store their own data.
The watch has insofar only been announced and can be preordered. Shoppers will be able to find them in stores starting the 21st of September. Traditionally, fitness trackers worked by using accelerometers or specialized lights. Apple’s watch reads the heart via electrodes on the reverse of the watch face that measure the heart's electrical signals. The associated app will record heart data in the form of detailed charts. On the watches face users can easily track their progress towards their daily step goal on an easy-to-read display.
This technology is especially helpful for recovering cardiac patients who need to exercise within a doctor prescribed heart range. The devices permit patients to avoid some of the anxiety associated with working out post heart event, outside of a doctor supervised setting. Use of such devices is likely to increase adherence to exercise prescription ultimately benefiting a patient’s recovery. Users can also upload workout data to social media to boost social support or for their personal trainers, a known motivator. Additionally, the watch tracks in the background for abnormal heart sounds and will alert users to arrhythmias.
Concerned users will also find peace of mind in the technology that allows Apple watch to track if a user may have fallen. In the event of such a fall, the watch will first offer to summon emergency services. After a full minute has passed with a user remaining inactive, emergency services will be contacted automatically. A text will also be sent out to preselected persons with an alert and your location.
Traditional EKG machines like the ones you might see in the fitness testing lab have 12 pads containing electrodes that are placed all over the body. Research at North Dakota State University has shown single pad EKGs, like on an Apple‘s latest watch, to be just as effective when measuring heart rate signals.
For those unwilling or unable to fork out the $499 for Apple's latest gadget there are a few reliable options. Although wearable wrist devices that depend on LED lights seem like an attractive option, studies have found them to be less accurate than chest straps containing electrodes. The greater accuracy of chest straps is a result not only of the proximity to the heart but also the technology used to read the heartbeat. Just like the Apple watch the heart straps typically use electrodes. Two of the more popular chest strap brands are Polar and Garmin, with models starting at about $60.
Sources: Journal of the America Medical Association, North Dakota State University