THE EFFICIENCY AND RELIABILITY OF FITNESS TRACKERS

The fitness trackers, or instructors of activity, are more popular than ever. Fitbit, Apple, Garmin, and Polar understood it. But should we rely on the data collected by these devices? Are these devices useful in helping to lose weight? Do they present risks?

You’re in the gym, on your stationary bike, and take a look around: your neighbors watch their watch every 30 seconds. Are they so eager to finish their training? No, no! They consult all their biometric statistics in real time: number of calories spent, number of steps taken during the day, heart rate. In the evening, many of them will also analyze the quality of their sleep through their device.

The general public quickly adopted fitness tracker for their personal use. Health and sports professionals, the military and even insurance companies also use these devices. No wonder the industry offers dozens of models, always more complicated.

Should we rely on the data displayed?

How do I know if the figures indicated by your Fitbit are the right ones? The question is excellent, but the answer is not so clear. Although many researchers have tried to evaluate the accuracy of activity monitors, the results are more or less convincing. First, because the methods of analysis differ from one study to another, but mainly because the duration of the research is so long that the models studied are outdated and replaced by a new version.

All in all, some conclusions can be drawn from these dozens of searches. According to a study published in 2018 in the International Journal of Exercise Science (1), most activity monitors lose their precision when physical activity intensifies. This means that the data displayed during the day quite valid, but this validity declines as part of a more intense physical exercise. Thus, the data on the number of steps is the most precise, those concerning the energy spent (calories) and sleep are less so.

The Fitbit brand’s product line seemed to demonstrate greater validity, but like other models, this accuracy falters with the intensity of the activity. These results are quite disappointing at the moment, but the technology evolves so quickly, these facts may be a thing from the past in a few years, maybe even a few months.

Motivation, activity volume and weight loss

Studies have shown that using a fitness tracker can increase the motivation to do physical activity. Achieving a set goal or going the extra mile can motivate a person to move more by choosing travel rather than email, the stairs instead of the elevator, the bike rather than the bus. The social aspect of activity monitors can also contribute to the motivation of the user. Comparing your data with those of your friends on social networks can push some people to surpass themselves.

Since people are more motivated and have more physical activity, they are easier to lose weight. Some research has proved that this type of device is sometimes more effective than online weight loss plans or medical follow-up the reason being that these people are in constant contact with their activity monitor.

The dark side of monitoring

Other researchers have concluded the opposite. Activity monitors may not offer advantages over conventional behavioral weight loss approaches. And a goal that is too high can quickly have the opposite effect. The 10,000 steps a day are not accessible to everyone.

But despite the generally noted motivation effect, life is not always rosy. The activity monitor often becomes an obstacle to physical activity and weight loss, especially in the long term. When you embark on a new training plan, the results are usually spectacular in the first few weeks. But after a while, you can reach a certain plateau, as much in terms of calories burned by training than pounds lost, which can quickly become demotivating.

Health status and fitness are not just calories or heart rate. It is a set of factors, including feelings of well-being, stress management ability, endurance, flexibility. An activity monitor does not give you insight into your flexibility or the strength you have gained.

And the risks in all this?

American Holistic Physician Andrew Weil answered a reader who was wondering about the risks associated with wearable technology.

In his article, he mentions that his primary concern about these devices is their propensity to generate anxiety, especially in people with eating disorders and those who advocate excessive exercise.

Dr. Weil also reports having some concerns about electromagnetic waves emitted by activity monitors. He quoted epidemiologist Devra Davis as saying: “The lack of scientific evidence on the harmfulness is not a proof of security. Just because research has not proven that activity monitors are harmful to health, just because they are safe is not enough.

The radiation emitted by these devices is similar, but of smaller amplitude, to cell phones classified as “potentially carcinogenic to the human being” by the WHO Cancer Research Agency.

Devra Davis also recommends removing the device from his wrist when going to bed, because the brain could be exposed to low-frequency waves when the hand is near the head. These waves can disrupt sleep and cause fatigue, drowsiness, loss of energy, and even weight gain. During the day, the epidemiologist mentions that it is better to opt for a device that is worn on the wrist than a band in the chest to keep it as far away as possible from the brain.

Electromagnetic waves are already ubiquitous in our environment. Choosing to do an outdoor activity (without monitoring) allows you to give a break to our body. These moments are rather rare nowadays.

The tracker’s fitness may have benefits, but they involve a rationalization of the fiscal year, in the end, while the opposite effect by generating stress, anxiety, and decreased pleasure.

If you had planned to offer an activity monitor to a loved one, why not opt for a gym membership, a group course registration or access to an online training platform instead?