What Xiaomi fitness bracelet shows: all metrics and hidden features

Xiaomi fitness bracelets have long become synonymous with affordable, but functional gadgets for health. 2014 In the last year, the lineup evolved into smart devices that can track dozens of parameters, from basic steps to blood oxygen levels. 20-30% The bracelet is capable of predicting a cold by changing heart rate or analyzing sleep phases to within minutes.

In this article, we will analyze in detail what data is collected by Xiaomi fitness bracelet (on the example of current models of Mi Band). 6/7/8 And the Smart Band Pro, how to interpret them correctly, and where to look at hidden metrics, and you'll learn why the bracelet sometimes shows unrealistic metrics. 20 000 How to distinguish deep sleep from superficial sleep, and why the stress level on the bracelet may not coincide with your well-being on the body 30-40%. We will also compare the accuracy of Xiaomi readings with medical devices and give a checklist for calibration of sensors.

Basic metrics: steps, distance and calories

The most obvious function of a fitness bracelet is to count steps. But how does it work? It's based on an accelerometer that records hand movements. Xiaomi algorithms analyze the amplitude, frequency and rhythm of vibrations, sifting out random gestures (for example, when you wave your hand in a transport). ±10-15% — The bracelet can count steps when knitting or even while sleeping if you toss restlessly.

To improve accuracy:

• 📱 Indicate in the Mi Fitness app your height, weight and step length (configured in the profile).
• 👟 Calibrate the bracelet once in a while. 2-3 month: walk exactly 50 steps, compare with the readings of the gadget and adjust the coefficient in the settings.
• 🚶‍♂️ Wear the bracelet on the non-dominant hand (for right-handers - left, for left-handers - right), so the sensors are less susceptible to interference.

The distance and calories burned are calculated automatically based on the steps, but the error is even higher here: 10 000 Steps uphill and on a flat road will be equal in calories, although in fact the difference can reach the level of the road. 200-300 For more accurate data, sync the bracelet with apps like Google Fit or Strava that use it. GPS smartphone.

2. Heart rate monitoring: how to read the pulse on Xiaomi

Sensor. PPG (Xiaomi's bracelet photoplethysmography measures the pulse by lighting the skin with green LEDs and analyzing reflected light. The technology is similar to that used in hospitals, but the accuracy of medical equipment is not expected. ±5-10 s/he may be in a position to be able to reach 15-20%.

What is important to know about pulse readings:

• ❤️‍🩺 Rest: The norm for an adult — 60-80 If the bracelet shows 90+ more dormant 3 For days on end, it is a reason to go to the doctor.
• 🏃 Load: maximum pulse is calculated by the formula 220 — age, by over-exceeding 10-15% signalizes overtraining.
• 😴 Sleep: the night pulse should be on 10-20% A sharp spike may indicate apnea or stress.

In the Mi Band models 7/8 Smart Band Pro added continuous pulse monitoring (each one) 1-5 This allows you to track heart rate variability (HRV), a key indicator of stress and fatigue. 20 MS) may indicate chronic fatigue or approaching illness.

💡

If the bracelet is constantly showing a pulse of 220 beats / min or absurdly low values (for example, 30 beats / min), reset it to the factory settings. PPG post-firmware update.

3.Sleep analysis: What phases and scores mean

Xiaomi fitness bracelets divide sleep into 4 phases:

1. Wake up (waking up in the middle of the night).
2. Light sleep (50-60% from total time) - restoration of muscles and immunity.
3. Deep sleep (15-25%) — Critical for memory and hormonal balance.
4. REM-sleep (20-25%) — The dream phase is important for mental health.

The bracelet gives a sleep score of 0 to 100, where:

• 🟢 90-100 — Perfect sleep (rarely found in healthy people).
• 🟡 80-89 — normal, but there are reserves for improvement.
• 🔴 Below 70 – chronic sleep deprivation or disturbances (apnea, insomnia).

How does Xiaomi define sleep phases? The algorithm analyzes:

• 📉 Movements (accelerometer records turns and rises).
• ❤️ Pulse (in the deep phase it is minimal, in the REM — unstable).
• 🌡️ Skin temperature (in new models).

But there are nuances:

⚠️ Note: Xiaomi's daytime nap bracelet doesn't recognize daytime naps correctly. If you take a 20-minute nap during the day, the device may count it as a "light nap" or ignore it altogether.

4. Blood oxygen levels (SpO₂): sound-off

Starting with the Mi Band 6, Xiaomi added a sensor SpO₂ — It measures the oxygen saturation of the blood as a percentage — 95-100%. Indicators below 92% may indicate:

• 😷 Lung diseases (including postcoid syndrome).
• 🛌 Sleep apnea (stop breathing during sleep).
• 🏔️ Acclimatization at a height (if you are in the mountains).

How does measurement work:

1. The bracelet shines red and infrared LEDs through your finger or wrist.
2. The sensor detects how much light has been absorbed (oxygen affects absorption).
3. The algorithm displays the saturation percentage.

Important:

• 🩹 Measure. SpO₂ in a calm state (sitting for 5 minutes without movement).
• 🔋 The charge of the bracelet should be above 20% - otherwise the sensor may fail.
• 🧴 The indicators are affected by tattoos, dirt on the skin or cold hands.

5 Stress Level and Energy Reserve: How It Works

The Stress Level feature appeared in Mi Band 7 and is based on heart rate variability (HRV) analysis. The algorithm assigns a score from 1 to 100, where:

• 🟢 1-30 — relaxation.
• 🟡 31-70 — Moderate stress (normal for the working day).
• 🔴 71-100 — High stress, risk of emotional burnout.

The Smart Band Pro adds "Energy Reserve," which is a measure of how much power is left for the day.

• 😴 Quality of sleep (deep phases give you sleep) +30% energy).
• ❤️‍🔥 Activity level (excessive loads reduce the supply).
• 🧠 Stress (every hour in the zone) 71-100 take away 5-10% energy).

How to reduce stress according to the bracelet:

6 Women's health and other hidden functions

The Mi Fitness app has a section on Women’s Health that tracks:

• 🩸 Menstrual cycle (prediction 3 months ahead).
• 🌡️ Ovulation (according to temperature and pulse).
• 😣 Symptoms of PMS (headache, mood swings).

Other little-known possibilities:

• 🏊 Swimming recognition: The bracelet automatically determines the style (brass, crawl) and counts the circles in the pool.
• 🎵 Music management: you can switch tracks on your smartphone directly from the bracelet.
• 🔦 Lantern: Mi Band 8 has LED screen lighting for night runs.

How to enable hidden functions:

1. Open Mi Fitness. → Device profile → Additional settings.
2. Activate Developer Mode (click 5 times on the firmware version).
3. The menu will feature options like Sleep Lab or Advanced Pulse Monitoring.

Comparison with medical devices: how accurate the data are

Independent tests (including studies by Stanford University and Which?) show that the accuracy of Xiaomi fitness bracelets varies:

The main sources of error:

• 👴 Age: in older people, pulse accuracy and SpO₂ lower due to impaired blood circulation.
• 🏋️ Intense loads: when running or cycling, sensors are confused due to vibrations.
• 🌡️ Ambient temperature: in the cold or in the sauna, the indicators may be distorted.

💡

Xiaomi fitness bracelets are suitable for trend analysis (tracking dynamics), but not for medical diagnosis, SpO₂ 88% or pulse 120 beats / min at rest - confirm the data by your doctor.

FAQ: Frequent questions about Xiaomi fitness bracelets