Most wearable fitness trackers are rather small and lightweight. Necessity says that they have to be in fact, in order for them to be usable during physical activity. And yet despite their small stature they can all do quite a lot, thanks to just a few tiny sensors nestled inside. But just how do fitness trackers work? How is this little electronic bracelet actually tracking the metrics it claims to? Here’s a brief look:
How Do Fitness Trackers Count Steps?
The step counter function on most fitness trackers is usually it’s most accurate – and some say most useful – function. It’s all achieved using basic motion sensors, the likes of which have been around for years, and a simple mathematical equation which turns the sensed motion into an actual step count.
How Do Fitness Trackers Count Calories Burned?
Almost all fitness trackers will offer a count of how many calories their user has burned, both as a basic guide to measure the effectiveness of the current ‘workout’ and a general motivational tool. After all, if you can ‘see’ that your extra morning walk has reaped real results in the form of 100 extra calories burned it is fairly powerful motivation to keep going the next day to burn even more. But just how is this little gadget calculating all of this?
Measuring calories burned accurately is no easy task. The majority of devices use a combination of their acceleration sensors and heart rate sensors and some basic mathematical algorithms. Because every individual is different – and has a different biological make up – the calorie count that is displayed is not 100% accurate – a study conducted using popular trackers like Nike Fuelband, Fitbit Ultra and Mi Band found it to be around 25% accurate for most – however as a rough guide it is rather good.
How Do Fitness Trackers Calculate Heart Rate?
At the heart of every fitness tracker’s functionality is its ability to measure your heart rate (excuse the slight pun.) This is achieved by an LED sending a tiny beam of light directly into the skin which then measures the amount of light which is reflected back. The amount of reflected light will change according to how fast your blood is circulating so that it becomes possible for the device to calculate your current heart rate. Pretty clever stuff right?
Do Fitness Trackers Actually Work?
Fitness trackers are trendy. We all know that by now. Basically in the minds of many your personal tech suite (smartphone, laptop, tablet, high end headphones etc.) is simply not complete unless you are sporting one version or another on your wrist on a daily basis. And they are indeed becoming more affordable every day, as cheaper, but robust alternatives to the higher end FitBit are appearing on the market.
Trends are cool, but as we all know science likes facts. That’s why the American Heart Association has just spent months examining, collating and verifying the results of 224 different studies that examined how different apps and wearables like a fitness tracker help people make real, positive changes in their lives. They obviously wanted to find out if they really worked. And, after all the work was done the answer was yes, it does indeed seem that they do.
How Fitness Trackers Are Really Helping
The studies that the AHA looked at were rather varied, covering the use of fitness wearables and apps across a number of different ‘fitness needs and interventions’, things like getting more exercise, losing more weight, getting better sleep and quitting bad habits like smoking and excessive drinking.
The results for the latter (quitting stuff) were only so-so but in the diet and exercise arenas wearables users fared well. In all cases participants – under medical supervision – did seem to do very well in terms of hitting their self-imposed goals. The pedometer function of the trackers seemed particularly effective, with many reporting that their little gadget provided them with just the right amount of challenge and motivation.
Experts of course point out that these studies are limited (usually they ran for just 6 months) and are working on more extensive research. But what has already been completed is work that the ADA – and many other global health experts, do find very promising. So if you need a little extra push to keep on track with your fitness plan it may be worth asking Santa to leave one in your stocking this year after all!