“Smart” bracelets: how they work, what they measure and can they be trusted Editorial articles

What it is

A fitness bracelet is a gadget that, in real time:

• monitors health indicators;
• measures the time spent performing exercises;
• shows the number of steps taken per day and calories burned;
• monitors other parameters necessary for training, weight loss and a healthy lifestyle.

Makes sports more effective. Allows you to track the dynamics of training and weight loss, constantly improving results.

Don't be confused!

Since this is know-how, there is still some confusion in definitions.

A fitness tracker is a broader concept. It includes absolutely all the gadgets (not just bracelets) necessary for the most effective sports activities. This includes applications on phones with the same functions, ordinary wristbands, and complex handheld personal computers. A fitness bracelet is just one of the trackers.

A weight loss bracelet is an ordinary piece of jewelry made of silicone or stones, which is worn on the wrist and affects a person with the power of energy waves. Despite the pseudoscientific principle of operation of such an accessory, Power Balance (one of the brands) was at the peak of popularity at one time.

Smart watches (smart watches, watch phones) are wearable computers that support third-party applications and are controlled by mobile operating systems. They perform the functions of media players, receive phone calls, SMS, and emails.

The table will help you understand the differences between fitness bracelets and smartwatches.

However, recently models have appeared on the market that are difficult to position only as a fitness bracelet or exclusively as a smart watch. This is due to the constant improvement of devices and the intertwining of their main functions.

From the history

1981

The first heart rate sensor was released, which was attached to the athlete's hand. It was distinguished by its large size and numerous wires, which created certain inconveniences in wearing. Especially during training or competitions. Performed a single function.

year 2000

Wireless heart rate monitoring has become available in consumer electronics.

year 2009

The first fitness bracelets appeared, most similar to modern ones. For greater measurement accuracy, they were supplemented with accelerometers and altimeters.

2010

They were taught to analyze the quality of sleep and calculate daily calorie consumption based on data received from the body.

year 2012

Models have appeared on the market that move away from the fitness direction into medicine. They give a signal when the heart rhythm goes astray and becomes pathological, preventing it from stopping. Allows you to monitor vital signs in sick and elderly people. They are actively used by athletes, for whom this data is also important.

Every year, fitness bracelets are improved and equipped with new functions.

Principle of operation

To understand how a fitness bracelet works, you need to understand its structure. Built-in sensors allow you to determine indicators. Depending on the models, there can be from 2 to 10. The more, the more multifunctional the accessory.

Accelerometer

A sensor with a counterweight that responds to body movement. Determines the number of steps taken and speed. Three- and six-axis accelerometers have maximum sensitivity, so they calculate indicators more accurately.

Gyroscope

A sensor that takes into account three-dimensional movement in space. Determines the angle of inclination of the bracelet in relation to the ground. Distinguishes walking from running, exercise and other physical activity.

GPS sensors

Makes calculations even more accurate. Allows you to plot the optimal route for walking or running. Models with the best GPS sensors: Garmin Vivosmart HR+, Samsung Gear Fit2 Pro, Huawei Band 2 Pro.

Heart rate sensor

Sensor with LEDs (working principle: photoplethysmography). Tracks how blood flow changes during different periods of heart pulsation. Controls heart rate during training and at rest.

Pressure meter

A sensor that calculates approximate (!) pressure based on heart rate, taking into account age and weight.

All information collected by the sensors is sent to a smartphone synchronized via Bluetooth with the fitness bracelet. There, in a more convenient format, you can see the optimal duration of sleep for your daily routine, the recommended daily caloric intake and the amount of energy spent, as well as many other points important for playing sports and a healthy lifestyle. How exactly the algorithms work to calculate such indicators is kept secret by the creators.

With the world - one by one. The fact that developers do not explain how calorie content or sleep duration is calculated in fitness gadgets does not always play into their hands. In 2013, a complaint was filed in California against Nike. The company was accused of deception: in advertising they stated that their Fuelband tracker tracks the burning of every calorie during exercise. But studies showed that the device did not take into account either physiological data or the level of activity for the day and always displayed the same number of calories burned. As a result, all Fuelband users were compensated.

Synchronization with smartphone

Among the advantages of a fitness tracker is the ability to connect it to a smartphone. To do this, you need a special application, which is usually downloaded and installed for free. After this, the bracelet will be able to:

• Inform the owner about incoming calls and SMS, messages on social networks;
• Ensure that the call is answered or reset by pressing the touch screen (this is especially important during training);
• Help in finding a smartphone using a special built-in function;
• From a distance, release the camera shutter on your smartphone.

A very convenient function is data transfer to a smartphone. All of them are saved in a special application and are available for analysis at any time. You can build a graph of your activity, study the dynamics of your heart rate over a certain period, monitor your caloric intake and weight changes.

Benefit

So, what is a fitness bracelet for? The main purpose is to increase the effectiveness of training.

Track activity

With it, you can track your daily physical activity: the number of steps taken, distance in kilometers and calories burned. People who are seriously involved in sports and focused on results (losing weight, building muscle mass, weight control) know exactly how many steps they need to take per day.

If the daily norm is 15,000, but the fitness bracelet shows only 13,000 at the end of the day, you urgently need to go for an extra walk or turn on the treadmill. Otherwise, at the end of the probationary period there will be no result.

It's the same with calories. How can you go to bed if you haven’t achieved an energy deficit during the day? This indicator allows you to decide whether you can eat an extra apple at night or if it’s too much and you’ll have to starve until the morning.

Monitor indicators

A fitness bracelet allows you to keep your physical condition under control: pulse, blood pressure, blood oxygen saturation. Why do breakdowns occur and the initially designed training programs are not completed? Because they incorrectly calculated the intensity - and already at the 5th minute of the lesson, the heart jumps out of the chest and suffers from shortness of breath. And then, after a couple of such experiments, the doctor forbids self-torture. The sports gadget reflects biological indicators and allows you to select a pace so that they remain within the normal range. As soon as your heart rate starts to go off scale, you need to slow down.

Or, for example, the goal of jogging is to lose weight. In this case, it is recommended to keep your heart rate at an average of 130 beats per minute (plus/minus taking into account age, weight and other individual characteristics). If this indicator changes in any direction, the fat burning process will slow down significantly and the workout may be in vain.

Enjoy nice bonuses

Fitness bracelets are loved by many for the additional features that their branded devices provide. For example, all weight loss dieters and athletes know how important sleep is for a healthy lifestyle. However, the general advice to sleep 8 hours a day is not always relevant. As scientists have proven, the duration is determined individually for each person. Plus, you need to correctly calculate when to go to bed and what time to get up, so as not to disturb the deep sleep phase. This gadget will automatically do all this and wake you up at the most opportune moment.

Some bracelets allow you to connect to social networks or create local accounts and post the results of your workouts for everyone to see. Since others are also actively doing this, a competitive moment arises, which provides additional motivation for training. Using this function, you can also find a partner for morning jogging in your city or for visiting a fitness club together.

Thus, fitness bracelets are useful for:

• losing weight;
• training;
• introduction to a healthy lifestyle;
• tracking health indicators.

In principle, we can say that absolutely everyone needs fitness bracelets in order to see specific figures for their daily activity and health indicators. For some, even the laziest, this becomes an incentive to get off the couch and go for a walk or give up their favorite burger.

Is an accessory always useful?

Most likely not always. This is the same technical device as a telephone or a computer, which can fail at any moment. Moreover, many doctors, athletes and simply people leading a healthy lifestyle are ardent opponents of “smart” assistants because of their inaccuracies in their work. Of course, with more expensive models, errors in measuring pulse or pressure are much less common, but they still cannot be excluded.

Most of the complaints come from inaccuracies in measuring the number of steps taken, pulse, blood pressure and all other indicators that the device should read automatically. Either the pulse is too high for a person in a calm state, or the running distance is not completely displayed on the device - such errors in bracelets, although rare, do occur.

Photo: istockphoto.com

Some have expressed dissatisfaction with the “smart” alarm clock. The watch should wake you up at the supposedly right moment in the light phase of sleep. That is, the bracelet, based on accelerometer readings, tracks the activity of your body during sleep. But very often the device wakes you up not because you are in a light sleep phase, but because of the slightest body movement. For example, if you just roll over to the other side. Experienced users say that no accessory can do the right sleep for you.

There are also many other disadvantages of fitness assistants: absolutely unnecessary functions, fast battery consumption, pseudo-freedom from a smartphone. But, of course, each model is individual and has its own advantages and disadvantages.

Scientists warn: active use of gadgets can cause overeating

Built-in functions

The usefulness and multitasking of fitness bracelets depends on the built-in functions. The basic ones for most are:

• heart rate monitor - shows heart rate;
• pedometer - determines the number of steps taken and mileage traveled;
• tonometer - records the approximate pressure;
• calorizer - counts calories burned;
• “smart” alarm clock - gives a signal at the right moment, taking into account the total duration of sleep and its phase;
• sleep monitoring - shows the state of the body at night;
• synchronization with phone.

In conditions of fierce competition, manufacturers equip their devices with numerous additional functions in order to attract as many buyers as possible. These could be indicators:

• water-salt balance;
• blood sugar levels;
• time of taking medications (vitamins, sports nutrition, weight loss products, medications);
• the amount of excess fluid in the tissues;
• percentage of visceral fat;
• breathing rhythm.

With their help you can configure:

• automatic sending of physical indicators to a doctor or trainer;
• remote monitoring of the health of relatives;
• list of goals and objectives, monitoring their achievement;
• reminder calendar.

In 2021, Garmin and Huawei launched a new feature for their bracelets - VO2 Max. It allows you to calculate the maximum amount of oxygen that the body can use during intense physical activity. Based on the data obtained, the gadget adapts to a person’s individual parameters and gives useful tips on which exercises will be most effective and how to properly create a training program.

Those who love swimming can buy a waterproof model that works at depth, in the bath, and while taking a shower. The screen glass can be super durable and protect your device from scratches and shocks. This allows you to use it even if you are into extreme sports.

It should be taken into account that fitness bracelets equipped with only basic functions (with a pedometer and heart rate monitor) are inexpensive. But for each additional option listed above you will have to pay extra.

How fitness bands track steps

The motion sensor built into the device is used as a pedometer. The movements of the bracelet, repeated in a certain way, are recorded as steps, their number is counted, after which the program counts their number for a certain period of time. If physical activity is insufficient, the bracelet and its program remind you to take a walk.

Different bracelets have step counting algorithms of varying quality. Some may mistakenly count as steps, for example, shaking in a car, while others increase the counter from ordinary hand waves. Therefore, this information should not be taken as completely accurate.

Advantages and disadvantages

Many people do not understand why spend money on such an expensive accessory if modern smartphones have a wide selection of applications that perform all the same functions. To answer this question, you need to evaluate the advantages and disadvantages of fitness bracelets.

Advantages:

• the data is saved without downloading additional programs (the smartphone will have to be loaded with many applications to perform all the necessary functions);
• data recording occurs unnoticed, without distracting, interfering or causing discomfort (the smartphone should always be carried with you, without letting go of your hands);
• One synchronization per day with a linked phone is enough (the smartphone must be constantly connected to the mobile Internet or GPS, which increases the cost of metered traffic);
• indicators are analyzed over a long period of time and saved (a smartphone can go astray and lose all received data, although this is rare);
• the programs of most fitness bracelets are easily synchronized with a computer/tablet/laptop and quickly open on them;
• lightness, almost weightlessness, which is not felt on the hand;
• long-term work in offline mode;
• functioning in any climatic conditions (even in severe frosts).

Flaws:

• not all models are distinguished by measurement accuracy, which depends on the brand, sensors and compliance with measurement rules;
• high prices;
• not compatible with all smartphone models;
• Too much time is spent tracking results, setting the correct settings, etc.

If saving money is a priority, then mobile applications on your phone that perform the functions of a heart rate monitor, pedometer and other indicators are the best option. If comfort and accuracy of the data obtained is more important, it is better to purchase a fitness bracelet.

Why do you need a notification function on a bracelet?

A very useful feature when working in conjunction with a mobile phone: even if the smartphone is located far away, for example, deep in a woman’s bag, the user will sense and will not miss a call or an important message. Almost every bracelet can also vibrate when notifications are missed. Application settings allow you to select specific applications for which the bracelet will respond to notifications with vibration. By default, it only alerts about incoming calls.

The function is aimed at highlighting important notifications, so you should not select many applications. In this case, it will be impossible to determine which program the notification came from, and it also consumes battery power.

Kinds

By functionality:

• multifunctional - with additional options;
• with limited functionality - with basic sensors.

By gender:

• female - with an elegant, stylish design, sophisticated, made in bright colors (Smart Bracelet H2 and QW16, Smart Band X6 Metal Gold, A80 Smart Watch, MyPads I9);
• men's - with a discreet, minimalist design, mostly black or dark blue.

Men's and women's fitness bracelets are no different in functionality.

By cost:

• mass market (from $15 to $50): Fitbug, BQ, Xiaomi Mi, Belsis;
• middle market (from $50 to $120): Jawbone, Huawei TalkBand, GearFit, Sony;
• premium (above $120): Fitbit, Mio Fuse, Samsung Gear Fit2 Pro, Polar A360 HR (Russia).

It is impossible to differentiate between smart trackers that are used exclusively for training and those that help you lose weight. All models combine both functions.

What types of fitness trackers are there?

Activity trackers are small wearable devices that measure a person's basic fitness levels. The ancestors of modern fitness gadgets appeared in the 19th century. For example, in 1895, engineer Curtis Veeder created a “cyclometer” for cyclists: the device counted the revolutions of a bicycle wheel and converted them into miles.

The first fitness trackers in the modern sense can be considered wireless heart rate monitors (heart rate monitors), created in the early 1980s for Finnish ski athletes.

A pedometer and heart rate monitor are the minimum set of functions of most modern gadgets. There are additional features: based on the collected data, the tracker can calculate how many calories you burned during the day and evaluate the quality of your sleep. Some manufacturers claim that their devices can also assess stress levels.

Perhaps the most common type of fitness trackers today are bracelets that are worn on the wrist or ankle. However, you can embed an activity counter into almost any object adjacent to the body. There are gadgets in the form of rings, pendants, underwear stickers and shoe insoles. Fitness trackers, in principle, can also be called smartphone applications that allow you to count the number of steps, record jogging routes, or keep a diary of workouts in the gym.

The fashion for activity trackers is associated with a general increase in interest in wearable devices. Analysts at CCS Insight note that the market for such gadgets is growing year by year. Manufacturers sold 121 million wearable devices in 2021, with 74 million of them (about 60%) being smartwatches and fitness trackers. Analysts believe that in 2021 it will be possible to sell about 142 million portable gadgets of various types, and in 2023 this number will grow to 260 million. However, CCS Insight estimates that sales of bracelets will decline over time, since many forms of fitness monitoring are also available in smartwatches.

Wearable devices are gaining popularity in Russia. Research of the Svyaznoy network | Euroset showed that in 2021 Russians bought 2.5 million portable gadgets. Fitness trackers became the best-selling product, purchased by 52% of wearable device buyers. Perhaps the fact is that a fitness bracelet is on average cheaper than a smart watch.

Criterias of choice

Fitness bracelets on the modern market are presented in a wide range. Therefore, a logical question arises: which one to choose, so as not to overpay for the brand and unnecessary functions. First, decide for what purpose the accessory is needed and what indicators matter. If you don't work with heart rate, a built-in heart rate monitor is optional. If you play sports simply to maintain physical fitness and are not on a diet, there is no need for a calorizer. When viewing the functionality, pay attention to these points.

Main criteria

1. The more built-in sensors, the more multifunctional the fitness bracelet.
2. A three- or six-axis accelerometer provides greater accuracy.
3. The presence of a screen is a convenient option, unlike models that display information only on a smartphone.
4. Shockproof, heavy-duty screen.
5. Charge duration: there are models that last for a month of uninterrupted operation, and there are those that will have to be recharged every 3-4 days.
6. Availability of additional features (maintaining a personal account, reminders).
7. Design. Choose the color of the strap that you like and that fits into the overall style.
8. Compatible with smartphone model.
9. Availability of several training modes (most often depending on the pace and type of sport).
10. Simplicity of the interface.

Waterproof

Separately, it is worth mentioning water resistance. It is important not only for swimming enthusiasts. There is always a risk of getting caught in the rain or forgetting to take off your bracelet before taking a shower. Therefore, it is better to choose models that are protected from water. Fitness trackers have several classes of water and dust resistance. You need to be able to understand them in order to purchase a truly high-quality accessory. The table will help with this:

Not all manufacturers use the International Protection Marking data presented in the table, despite the fact that they are regulated by IEC standards (DIN, GOST). As an alternative, WR (Water Resistant) and ATM (atmosphere, pressure) indicators are sometimes used. If the instructions indicate these letter abbreviations, you should use another table:

Functionality

The following table will provide assistance in choosing fitness bracelets, taking into account your preferred sport, goals, built-in sensors and additional functions:

Compatibility

Fitness bracelets only function in tandem with smartphones. Therefore, when purchasing, you should definitely pay attention to whether the gadget is compatible with your phone’s operating system - iOS or Android. Review of applications for smooth operation of trackers:

General comparative analysis of some models according to different criteria

Waterproof

Another of the most important criteria when choosing a “smart watch” is their protection from dust and liquids. There are two main classifications of devices based on their water resistance:

• The IP degree of protection means the protection of the device from the penetration of liquids and dust. The level of protection is indicated by two numbers, the first of which means the degree of protection from solid objects (from 0 to 6, where 6 is complete protection from contact with dust), the second number is the degree of protection from water (from 0 to 8, where 8 is devices able to withstand prolonged immersion in water).
• The water resistance rating of WR watches can vary from WR20 to WR200, where the latter is marked for devices intended for divers (with the maximum degree of protection and complete water resistance). The digital designation in the marking indicates the depth of possible immersion of the device.

Please note that the water resistance markings installed by the manufacturer on fitness bracelets are conditional and in reality may not correspond to the statements. For example, it is not recommended to swim in fitness bracelets whose markings are below WR50 or IP68. And diving and diving are only allowed with trackers marked higher than WR100. Sometimes manufacturers themselves indicate whether their gadgets are suitable for swimming or whether they should be limited to a shower.

If you don’t plan to regularly swim with a fitness bracelet, but are looking for a reliable tracker that you can leave on before washing your hands, that can withstand splashes of water, rain and drops of sweat, then you should limit yourself to dust and moisture protection according to the IP67 standard or water resistance marked WR30 .

It is better not to purchase devices that lack moisture protection: if the watch is exposed to rain or accidentally drowned, it runs the risk of failure.

If you are looking for a fitness bracelet with maximum water resistance, with which you could regularly visit the pool and monitor your swims, we recommend that you take a look at the following rating:

The best fitness bracelets for swimming

If you are simply interested in smart trackers with household water resistance, then we recommend that you pay attention to the following rating:

The best waterproof fitness bands

How to use

How to turn it on:

1. After purchase, put it on the charger that comes with the kit. After this, the bracelet will turn on automatically.
2. Install a special application on your phone via Google Play Market or AppStore.
3. Open, log in, find the pairing screen and select your tracker from the available ones.
4. Synchronization will take some time, after which you will receive a notification that the pairing process is complete.
5. After this, you can set the desired settings.

How to setup:

1. Indicate the hand on which the bracelet will be worn. The accuracy of its work depends on this.
2. Check the boxes next to the parameters that will be displayed. Mark only those that need to be worked on. If you don't count calories, you don't need them. If you do not monitor your heart rate, remove the mark.
3. Set the time format if there is a clock. If you are keeping track of time, make them larger and brighter.
4. Activate the bracelet to turn on when you raise your hand. This will increase battery life.
5. Select when it is convenient to track your heart rate: only during sleep, only during training, or constantly.
6. Enable or disable sleep monitoring and smart alarm clock.
7. In some models, you need to work with settings for notifications about calls, SMS, goal achievements, and applications. Determine which ones are important and which ones should be discarded.

It is more convenient to set the settings through the mobile application immediately after installation on the phone.

How to wear:

1. Wear on your less active hand for more accurate results. Right-handers - on the left, left-handers - on the right.
2. Don't change hands.
3. If you have a heart rate monitor and blood pressure monitor, wear it at a distance of 2-3 cm from the palm so that the LEDs that track your heart rate and pressure pass over the line of blood vessels.
4. The capsule (back side of the screen) should fit snugly to your hand.
5. At the same time, do not tighten the strap too tightly - this may distort the accuracy of the data obtained.
6. Once a day it is necessary to remove it to allow the skin to breathe. This is especially true for silicone devices, under which moisture often accumulates, causing irritation and erosion.
7. A regular watch should be positioned above a fitness bracelet.
8. Simultaneous wearing of a fitness bracelet, a regular watch and jewelry made of any metal is not prohibited.

Fitness bracelets must be regularly cleaned with special aerosols, as they come into contact with pathogenic microorganisms on the skin, micro-discharges, and then can become a source of infection. The rules on how to do this are usually described in detail in the attached instructions. If a branded cleaning liquid is not available, a soda or soap solution can be a substitute.

It is also worth regularly checking the straps for signs of wear and tightening the screws, if any.

Review and functions of fitness bracelets

Acer Liquid Leap. Functions: pedometer, sleep tracker, distance, calories, alarm clock, clock. Remote control function for music player. Synchronization with smartphone: Android, Windows, iOS. Interface: Bluetooth. Battery: Li-Ion 70 mAh, operating time up to 144 hours (6 days). The tracker body is made of plastic, the strap is silicone, removable. Dust and moisture protection standard: IPX4, but you cannot swim with it. Display: 1” OLED 128×32 pixels, monochrome. Device weight: 18 grams. Kit: the fitness bracelet itself, USB-microUSB cable, charging cradle, instructions and warranty card.

Atrix ProFit Tempo E06. Functions: pedometer, clock, sleep tracker, calorie counter, alarm clock. Control your smartphone camera, call and message notifications from your phone. Synchronization: Android, iOS. Interface: Bluetooth. Battery: Li-Ion 40 mAh, operating time up to 100 hours (4 days). The case is made of plastic, the strap is rubber, removable. Dust and moisture protection standard: IP57. Display: 1” OLED 128×32 pixels, monochrome. Device weight: 23 grams. Kit: bracelet, USB charging cradle, instructions and warranty card.

Cubot V1 Smart Band. Functions: pedometer, calorie consumption, distance traveled, daily activity, clock, calendar, alarm clock. Notifications about calls and messages from your phone. Synchronization: Android, iOS. Interface: Bluetooth. Battery: Li-Ion 80 mAh, operating time up to 720 hours (1 month). The case is plastic, the strap is rubber, removable. Dust and moisture protection standard: IP65. Display: 0.88” OLED 128×32 pixels, monochrome. Device weight: 22 grams. Kit: bracelet, charger, microUSB cable, instructions and warranty card.

Fitbit Surge. Functions: pedometer, pulse, distance, calories, floors, GPS module, sleep tracker, clock, calendar, alarm clock. Notifications about calls and messages from your phone, music control. Synchronization: Android/iOS. Interface: Bluetooth. Battery: Li-Pol, operating time up to 120 hours (5 days). The case is made of metal, the strap is rubber, non-removable. Dust and moisture protection standard: IP65, you cannot swim with it. Display: monochrome. Weight: n/a. Set: bracelet, branded charging cable, instructions and warranty card.

Garmin Vivofit 2. Functions: pedometer, distance, calories, sleep tracker, clock, calendar, alarm clock. Sound notification of inactivity, saving data on the Internet. Synchronization: Android, iOS. Interface: Bluetooth. Battery: CR1632 battery, max operating time 8-12 months. The case is plastic, the strap is rubber, removable. Dust and moisture protection standard: IP55. Display: 1.06” monochrome. Device weight: 26 grams. Set: bracelet, replaceable second strap, USB dongle for pairing with PC Windows, Mac OS), instructions and warranty card.

Garmin Vivosmart. Functions: pedometer, calories, distance, heart rate monitor (optional), sleep tracker, stopwatch, clock, calendar. Notification via vibration of incoming messages and calls. Synchronization: Android, iOS. Interface: Bluetooth. Battery: Li-Ion, max operating time 168 hours (7 days). The case is plastic, the strap is rubber. Dust and moisture protection standard: IP55. Display: 1.06” OLED, monochrome. Device weight: n/a. Set: bracelet, branded charger, cord-clip for synchronization with a PC, instructions and warranty card.

Huawei Talkband B3. Functions: pedometer, calories, distance, sleep tracker, clock, calendar, smart alarm clock. Headset: speakerphone. Synchronization: Android, iOS. Interface: Bluetooth. Battery: Li-Ion 91 mAh, operating time 144 hours, or 6 hours in headset mode. The case is made of stainless steel, the display is covered with glass, the strap is leather/rubber/metal. Dust and moisture protection standard: IP57. Display: PMOLED 128x80 pixels, monochrome. Device weight: 96 grams. Kit: bracelet headset, microUSB cable, instructions and warranty card.

iFit Vue. Functions: pedometer, calories, distance, heart rate monitor (optional), sleep tracker, daily activity, clock, calendar. 24/7 communication with your smartphone, notifications about messages and calls. Synchronization: Android, iOS. Interface: Bluetooth. Battery: Li-Ion, up to 7 days of battery life. The case is plastic, the strap is rubber, removable. Dust and moisture protection standard: IPX7. Display: OLED, monochrome. Device weight: n/a. Set: fitness bracelet, two replaceable straps S/M and L/XL, charger, instructions and warranty card.

iHealth AM3. Functions: pedometer, calories, distance, sleep tracker, calendar, clock, smart alarm clock. Vibration alert. Synchronization: iOS exclusively. Interface: Bluetooth. Battery: Li-Ion 165 mAh, max operating time 168 hours (7 days). The case is plastic, the strap is rubber, removable. Dust and moisture protection standard: IP67. The display is monochrome. Device weight: n/a. Kit: tracker, two replaceable straps, two clips for carrying on a pocket, microUSB cable for charging, instructions and warranty card.

Jawbone UP4. Functions: pedometer, calories, sleep tracker, body condition and physical activity results. Vibration notification about incoming messages and calls from your phone. Synchronization: iOS exclusively. Interface: Bluetooth. Battery: Li-Ion 38 mAh, operating time up to 168 hours (7 days). The case is plastic, the strap is rubber, non-removable. Dust and moisture protection standard: IP68. Display: absent, instead there are 3 LEDs. Device weight: 29 grams. Kit: bracelet, branded cord for charging and synchronizing with a PC, instructions and warranty card.

Meizu Band. Functions: daily activity tracking, pedometer, sleep tracker, heart rate, sedentary time. Notifications about incoming messages and calls from your phone. Synchronization: Android, iOS. Interface: Bluetooth. Battery: Li-Ion, up to 360 hours of operation (15 days). The case is plastic, the bracelet is rubber, non-removable. Dust and moisture protection standard: IP67. Display: OLED, monochrome. Device weight: 20 grams. Kit: bracelet, magnetic charging dock, instructions and warranty card.

Ratings

Overall TOP 10:

1. Samsung Gear Fit2 Pro (Vietnam). $200.
2. Polar A360 HR (Russia). $150.
3. Fitbit Charge 2 (China). $140.
4. Sony SmartBand 2 SWR12 (Japan). $90.
5. Garmin Vivofit 3 (USA). $70.
6. Huawei Honor Band (China). $70.
7. Amazfit Cor (China). $50.
8. Jawbone UP24 (USA). $45.
9. Xiaomi MiBand 3 (China). $30.
10. Iwown i6 HR (China). $25.

The best fitness bracelets for sports:

1. Huawei Fit is an ideal choice for runners.
2. Fitbit Flex 2 is a versatile device that allows you to work in different sports, including swimming.
3. Asus ZenWatch 3 is a tracker for professional athletes whose workload is maximum.
4. Garmin Vivosport is a smart bracelet for the laziest, as it motivates to move more.
5. Xiaomi Mi Band 3 is an economical but multifunctional device suitable for beginners.

Best choice for weight loss:

1. Fitbit Flex - help in creating cardio programs
2. Jawbone UP3 - an opportunity to lose weight without harm to your health.
3. Garmin Vivosmart HR is a multifunctional weight loss gadget.
4. Sony SmartBand 2 - tuned to reduce weight.

The best fitness bracelets with blood pressure measurement:

1. Smart Band M3.
2. Jet Sport FT-7.
3. QS 100.
4. Gsmin WR32S.
5. ZDK i8.
6. Smart Bracelet M2.
7. Gsmin C1 Plus.
8. KaiHai H66 (sold on Aliexpress).
9. Bizzaro F330 (best value for money).
10. Qumann QSB 08 (lightest and most compact).

The newest fitness bracelets (best sellers in 2021):

1. Samsung Gear Fit2 Pro. $200.
2. Fitbit Charge 3. $170.
3. Polar A370. $160.
4. Garmin Vivosmart HR+. $150.
5. Huawei Band 3 Pro. $70.
6. Garmin Vivofit 4. $70.
7. Amazfit Cor. $50.
8. Honor Band 4. $40.
9. Xiaomi Mi Band 3. $30.
10. Honor Band 4 Running Edition. $25.

The production of modern fitness bracelets can only be compared with the release of new iPods. In conditions of fierce competition, brands try to regularly update models, equipping them with numerous additional functions. Those who cannot imagine life without this “smart” and useful gadget constantly monitor the release of new products.

Heart rate monitor - how it works and what is the accuracy

The technology that powers the heart rate monitor is called photoplethysmography.

. It involves the use of green LEDs that emit light and detectors that record the level of its reflection. When the heart contracts, blood pressure increases and capillary blood flow increases. As a result, more of the light emitted by the LED is absorbed, which is detected by the detector. Based on the information received, the pulse is determined.

This is a convenient feature for people who monitor their heart rate during sports training, daily activities and even sleep. For the readings to be as accurate as possible, the bracelet must fit tightly to the surface of the skin.

In any case, the fitness bracelet is not an accurate medical device, so the pulse is measured with a small error. A characteristic feature of this method of measuring heart rate is that the error increases with increasing heart rate, starting from 100 beats per minute. But at rest, the error of the heart rate monitor, as a rule, does not exceed 2%.

If you are looking for a fitness bracelet that would accurately measure your heart rate at rest and have minimal error when playing sports, we recommend that you take a look at this rating:

The best fitness bracelets with accurate heart rate measurement

What is the device

A fitness bracelet (or fitness tracker) is a smart device in the form of a neat rubber wristband. The texture of the material is dense and pleasant to the touch. The width of the product does not exceed 1.5-2 cm.

The fitness bracelet was invented shortly before the development of the first smartwatch. His popularity quickly skyrocketed. Users include both professional athletes and people from other circles.

The word “fitness” in the name determines the main purpose of the device. But! The product can be used not only in sports activities. This is its main feature. The functions of the fitness bracelet are applicable and useful in the everyday life of every person. More details about them are written below. Let's take a closer look at the types.

What's wrong with fitness trackers?

So, modern fitness bracelets can measure many health indicators, while technology is constantly evolving. What could go wrong?

One of the main complaints about activity trackers available to the average user concerns how accurate their measurements are. The bracelets do a good job of counting steps, but they have difficulties with more complex functions, including a heart rate monitor.

Many bracelet manufacturers, such as Fitbit and Garmin, specifically warn consumers that their accessories should not be used as medical devices.

But sometimes the accuracy of the devices is not enough for home use. In 2021, a California court considered a class action lawsuit from buyers of Fitbit bracelets: the plaintiffs stated that the gadgets are “extremely inaccurate and often cannot measure heart rate at all.” Their claim, however, was rejected.

Sometimes low measurement accuracy is a consequence of the design of the fitness bracelet itself. For example, the light signal that allows you to register your pulse is very weak: interference caused by movement is much stronger and often drowns it out. To get more accurate results, app algorithms can simply ignore data recorded during active training (which is the fun part!).

Inaccurate heart rate measurement is possible even while walking, a group of scientists from the UK, Portugal and Georgia was convinced of this. Participants in this experiment wore four identical fitness bands—two on each wrist—and were given four noticeably different schedules after “walking” on a treadmill.

Manufacturers of trackers often position them as a tool that will help you change your lifestyle and achieve certain goals, such as losing excess weight. Unfortunately, research shows that this tool does not always work. For example, in 2021, scientists summed up the results of an experiment involving about 800 residents of Singapore. Volunteers wore the tracker pendant for a year. It turned out that they devoted an average of half an hour more per week to physical education than people in the control group. However, this did not affect their health in any way: their body weight and blood pressure indicators did not change on average a year later.

Most of the 470 participants in the study conducted at the University of Pittsburgh did not achieve what they wanted either.

Those who did not wear the tracker lost an average of 3.6 kg more than the volunteers in the experimental group.

These studies are some of the largest and longest studies of the effects of fitness trackers; it is much more common to conduct short experiments on small groups.

Why did the trackers, despite the promises of marketers, not work? Scientists from Singapore rightly note that gadgets themselves can only track activity, but do not always motivate a person to increase their load. In addition, many participants quickly stopped wearing the accessory - perhaps they were simply tired of the tracker.

Sometimes tracking even plays a cruel joke on the user, forcing him to move less actively than before using the gadget. Participants in popular healthy lifestyle challenges sometimes fall into this trap when they strive to walk a certain number of steps per day. Some reported skipping intense but short runs or gym workouts in favor of long walks to reward themselves with higher numbers on their pedometer. At the same time, studies show that relatively intense cardio exercises (of course, if there are no contraindications to them) reduce the risk of developing heart and vascular diseases, so you should not neglect them.

Functions of these devices

Fitness watches also have other functions:

1. Pedometer
   – the accuracy of this function can range from 3% to 30%. He may react to fidgeting in one place or driving over uneven terrain in a vehicle. Of course, such failed steps initially lead to bewilderment, but with practice a person begins to correctly identify important information from the device.
2. Sleep analysis
   is another important function that will help you monitor the quality of your rest, which will make it possible to avoid many health problems.
3. Inactivity time
   - this function is not included in all sports watches for fitness, but it monitors your activity, if you have been sitting longer than expected, it will spur you into action and make you move.
4. Calories burned
   – to calculate this information, the devices take into account your overall activity along with your height, weight and age. By monitoring the calorie content of foods and overall activity, you can calculate the amount of weight gain or loss. This calculation leads to its own motivation.

What you should pay attention to when choosing a fitness bracelet

When choosing a fitness tracker, consider the following points:

1. Purpose of the device. For weight loss and amateur training, a simple pedometer with a calorie counter function is suitable. The athlete will need a device with a large number of sensors.
2. Functionality. Consider which options will be used regularly. Sometimes it makes no sense to pay extra for auxiliary functionality.
3. Moisture protection class. This parameter is taken into account by users who want to wear a watch all the time or go to the pool.
4. Smartphone compatible. You need to clarify whether the phone is capable of synchronizing with the selected bracelet.
5. Battery life.
6. Availability of display.

The design is selected taking into account the user's wishes.

Gadget functions

The functionality of the device depends on its focus, brand and price. “Sophisticated” sports models from well-known companies include additional capabilities. The average smart bracelet must be able to:

• Count steps
• Monitor pulse and heartbeat
• Determine sleep time
• Wake up smart
• Measure calories burned

All these features are useful and applicable in everyday life. Thanks to them, you can easily monitor your health and improve it. Let's take a closer look at the main abilities.

Heart rate monitor

This feature comes first. Most often, the product is purchased specifically for the convenience of counting heart rate, for example, while jogging.

The goal of each load requires a certain heart rate. If it exceeds the norm or underestimates it, the proper result will not be achieved. While jogging, a fitness bracelet helps you control your heart rate within the required limits. Providing accurate indicators, the gadget is an indispensable assistant in any training.

Sleep monitoring

Controlling rest time is important for all users. In the modern rhythm of life, normal sleep is disrupted. Its correctness affects not only the state of health, but also the rate of human aging. The product shows the correct rest in accordance with the daily load. The word “load” refers not only to physical activity, but also to general strenuous daily activity. Thanks to constant wear, the gadget detects the level of fatigue and sets the desired sleep time. The device also tracks phases and keeps statistics on healthy rest.

Smart alarm clock

This feature is tailored to the individual needs of the user and is directly related to sleep monitoring. By monitoring the degree of fatigue, the device wakes up the owner based on benefit. Based on indicators of daily activity and the desired quality of sleep, the “smart” alarm clock itself decides when to wake up. There is no need to start it manually for this.

For the function to work properly, wear the fitness bracelet on your hand without taking it off.

This contributes to the clarity of indicators. If you remove the device, it will not be able to accurately capture all the necessary data. This will prevent further operation of the alarm clock.

What can modern fitness bracelets do?

The simplest activity tracking is to count the distance traveled. You don’t even need a special device to do this, just a pedometer app that uses the built-in accelerometer of your smartphone.

Another important function, heart rate measurement, was introduced thanks to photoplethysmography technology. With its help, you can track blood flow, observing how the volume of blood vessels changes. To do this, the tracker transmits light through the skin using a small LED on the surface of the gadget adjacent to the skin. An optical sensor then records how much light is absorbed by the body's tissues and blood and how much is reflected back. Blood absorbs light more intensely than surrounding tissue. As the blood vessel expands and contracts due to the contractions of the heart, the amount of light reflected from the skin also changes. Based on these fluctuations, you can calculate how your heart rate changes during physical activity - during walking or intense training.

Fitness trackers also track daily energy consumption; this feature is useful for those who count calories consumed and burned. First, the bracelet-compatible app calculates your basal metabolic rate.

The basal metabolic rate is the minimum amount of energy that is needed to maintain life in our usual conditions.

This energy is enough to ensure that the body temperature does not drop noticeably below the normal 36.6 ° C, and all the main systems of the body work without interruption, ensuring breathing, blood circulation, chemical reactions in cells and the constant synthesis of hormones. To roughly calculate this indicator, it is enough to know the person’s age, gender, weight and height. The application adds the number of calories “burned” during walks, runs and workouts to the basal metabolic rate figures. This indicator is also calculated approximately - we will return to the problem of measurement accuracy later.

Another important sensor of modern trackers is a thermometer. It will help you notice an unusual increase in temperature in time: for example, it may rise if the workout is too intense.

Some trackers promise to monitor the quality of your sleep. For this, the same device is used that is responsible for measuring the number of steps - the built-in accelerometer of the fitness bracelet. The nature of the movements allows you to find out how much time a person spends sleeping, how often he wakes up and how quickly he can fall asleep again after waking up.

A feature that raises many questions among potential buyers of fitness bracelets is stress control. How does the gadget read the body’s reaction to increased stress, including psychological? Typically, one of its main sensors, the heart rate monitor, is responsible for “monitoring stress” using a bracelet. With its help, the tracker measures the degree of heart rate variability (HRV). The duration of the interval between two heartbeats normally varies slightly from cycle to cycle. Low variability, that is, uniform intervals between beats, may indicate a high load on the heart and blood vessels.

Some studies have linked low heart rate variability to an increased risk of heart disease and increased mortality.

Also, a low score may indicate that the body is in a “fight or flight” state: in this state, the body mobilizes to get rid of the threat as quickly as possible. In a critical situation, such a reaction can really save a life, but it can also be triggered by unpleasant but not dangerous events, for example, a conflict at work. The more often such a reaction occurs, the more it exhausts the body, and the inability to properly rest immediately after an unpleasant event exacerbates the problem. Such stress does not help to adapt to the new, but, on the contrary, only harms.

Number of steps taken

Fitness trackers measure K. Ricchio, P. Lyter, JM Palao. Reliability of fitness trackers at different prices for measuring steps and heart rate: a pilot study / Central European Journal of Sport Sciences and Medicine steps using a 3D accelerometer - a chip that helps determine how fast and in what direction the device is moving.

Also, most modern models have a gyroscope, which determines the angles and speed of rotation of the device, and a magnetometer, an electronic compass that calculates the orientation relative to magnetic north. Due to these measurements, fitness bracelets well determine the movement of the hand in space.

Reviewed by KR Evenson, MM Goto, RD Furberg. Systematic review of the validity and reliability of consumer-wearable activity trackers / The international journal of behavioral nutrition and physical activity 22 scientific papers concluded that fitness trackers quite accurately determine the steps taken. Although some (Fitbit One, Flex, Ultra) underestimate slow (2 km/h) walking on a treadmill.

In a study by F. El-Amrawy, B. Pharm, M. I. Nounou. Are Currently Available Wearable Devices for Activity Tracking and Heart Rate Monitoring Accurate, Precise, and Medically Beneficial? / Healthcare informatics research using 17 trackers, including Apple Watch, several Samsung Gear models, Garmin Vivofit, Mi Band and others, also found that trackers and smartwatches provide an accuracy of 92.8–99.7%. The best performance was provided by Apple Watch and MisFit Shine.

Moreover, the accuracy of the calculations seems to depend on the type of activity.

Thus, in one study, MB Nelson, LA Kaminsky, DC Dickin, AHK Montoye. Validity of Consumer-Based Physical Activity Monitors for Specific Activity Types / Medicine and science in sports and exercise trackers Fitbits One, Zip, Flex and Jawbone UP24 gave an error of only 4% during different types of walking in the laboratory, but began to wildly lie when people began to do ordinary things like cleaning the room or working in the garden.

During such activity, some gadgets underestimated the number of steps by more than twice. And only Fitbit Flex showed a more or less accurate result, missing only 47 steps.

Regarding the total number of steps per day, in a study by Y. Bai, C. Tompkins, N. Gell. Comprehensive comparison of Apple Watch and Fitbit monitors in a free‑living setting / PLoS One Apple Watch 2, Fitbit Charge 2 and Alta found that smartwatches and trackers erred by about 10–15%, while increasing the number of steps taken.

Bottom line: If you walk at a normal speed of 4-5 km/h, the fitness tracker will most likely show you the correct number of steps. But when doing homework or walking slowly along a path, you shouldn’t particularly hope for accuracy.

In any case, the error is not that big, and if instead of 10,000 steps you actually walked 8,500 or 11,500, this will not affect your health.