Electronic Fitness Trackers.

Electronic Fitness Trackers

The Origin of Fitness Trackers:

Fitness Tracker

            Fitness trackers are devices that are used by people to keep track of various body parameters like pulse, step detection, heart rate variability, blood oxygenation, body temperature, and such others.  There are wearable as well as non-wearable trackers.  They are aided by the wireless heart rate monitors in the polar watches of the 1980's. Later, mobile phones incorporated 3D accelerometers which measure movement and vibration in a three-dimensional space.  Fitness trackers also track sleep using a process named actigraphy.  It translates wrist movements into sleep patterns. Though it is a useful guide, it is not as accurate as polysomnography, which is used by the experts to measure sleep in a lab, and also monitor brain activity.

The process of Fitness Tracking:

Fitness Tracker

            Wearable fitness trackers require the users physiological details such as their weight, height, gender to gather accurate data.  There are numerous sensors added to a tracker, but motion sensors are the most numerous sensors added to a tracker, but motion sensors are the most commonly used sensors to determine body movements.  Wearable trackers continuously sense the movements of the body on a 3 axis accelerometer.  The data is recorded throughout, since the time it is worn and powered up.  It enables the tracker to trace if the individual is walking forward, running fast, or even standing still.  The collected data is stored in the tracker for further processing.  Processing occurs when the data is transferred to the software associated with the fitness tracker on the smartphone or laptop with which it is synced.  The data collected is later run through a personalized algorithm.  This makes it possible for the software to detect what the different movements recorded actually imply.  It categorizes the movements into different activities and then generates more information based on these details.  These are usually stored under different headings in the fitness tracker app.

Fitness Tracker

            The app gives details such as how many steps have been taken, the speed and pace of the individual, and even the number of calories likely to have been burnt.  In this way, fitness trackers help an individual in self-monitoring their activities.  Fitness trackers measure motion.  Most of today's wearable trackers come with a 3-axis accelerometer to track movement in every direction, and some come with a gyroscope too to measure orientation and rotation.  The data collected is then converted into steps and activity and from there, into calories and sleep quality. Then there's the altimeter that can measure your altitude.  The information is collected to create an overall reading.

            Most trackers like Jawbone UP3 have temperature sensors and a bio impedance sensor alongside the familiar accelerometer that is already mentioned.  The sensors measure the acceleration, frequency, duration, intensity and patterns of your movement.  Bio impedance sensors check the resistance of the skin to a tiny electric current, and the four electrodes on the inside of the UP3 fitness tracker are clearly visible.

Fitness

            Other wearables, such as the Fitbit Charge 2, use optical sensors to shine  a light on the skin and measure the pulse through it.  The light illuminates capillaries, then a sensor measures the rate at which blood is being pumped.