How to Use Galaxy Watch 4’s Body Composition Feature and Is It Accurate?

The Samsung Galaxy Watch 4 continues to surprise us all. Dubbed as the true smartwatch Android users were waiting for, the Galaxy Watch 4 packs an impressive array of features. From a plethora of Galaxy Watch Faces to using Spotify offline, there is a lot to look forward to. However, one of the highlight features of the Watch 4 is the BIA sensor and its ability to keep your health goals on track by giving you a smart analysis of your body. But what exactly is this sensor, how do you use it, and is it actually accurate? This is exactly what we aim to find out and show in this in-depth guide about the Samsung Galaxy Watch 4’s body composition sensor and its usage.

Galaxy Watch 4’s Body Composition Feature

While this guide will show you how to measure your body composition through the Galaxy Watch 4, we will also talk about the Watch’s BIA sensor and what it does. If you’re already caught up with the basics and just want the h0w-to, use the table below to jump to the section.

What Is the BIA Sensor in Galaxy Watch 4

For those not initiated to the immense features of the Galaxy Watch 4, the BIA stands for Bioelectrical Impedance Analysis. Part of the wellness suite of the Galaxy Watch 4, the BIA sensor is responsible for checking a host of your health metrics. The Galaxy Watch 4’s sensor collects health data from over 2,400 points and paints a virtual picture of your body composition including your body fat among other things. You will understand the experience if you’ve ever used a smart scale that requires you to place your feet over four metal sensors.

{}
BIA Sensor

The BIA sensor of the Galaxy Watch 4 works in the same way and after a few seconds dishes out a slew of results you can use to monitor your health and fitness regime. However, the difference here is the Galaxy Watch 4 requires you to place two of your fingers to perform its process. The BIA sensor of the Watch 4 has proven to be an incredible tool and arguably the first of its kind not seen in smartwatches before. This spells incredible opportunity for fitness enthusiasts and makes the Galaxy Watch 4 a vital tool for health compromised individuals who need to keep a tab on their body vigorously.

How Does It Work?

Since the BIA sensor in the Galaxy Watch 4 measures your body composition, it works on the same principle as BMI scales. While there are different ways to measure a person’s body composition, Samsung’s new Exynos W920 chipset present in the Galaxy Watch 4 and Classic relies on current resistance. The BIA sensor present in the watch requires users to position the underside of their wrist opposite the watch and place their middle and ring fingers on the two buttons.

middle and ring finger

Post that, the watch sends a series of low voltage currents to the body which in a way act like a complete circuit starting from one finger and ending at the next. Since our body is made up of different impedances of fat, water, muscle tissue, and bone, this signal is affected by them as it passes through. The collected data is sent through Samsung’s own algorithms. This process takes around 15 seconds to complete and at the end, users get the results comprising of their individual factors. Electrical analysis for measuring body composition has picked up a lot of steam in recent times and is used by an immense number of weighing scales.

touch your watch only galaxy watch 4

However, a thing that should be made clear is the Galaxy Watch 4’s BIA sensor is incapable of measuring weight. At the beginning of your body composition test, you must input your current weight so the gathered results can be cross-run alongside it to spit out an accurate analysis. While you can go ahead and guess your weight and run the test, it’s heavily advised to keep a weighing scale handy so you input the proper data.

What Metrics Does It Measure?

BIA details

The Samsung Galaxy Watch 4’s body composition sensor analyzes and tests the most important factors related to your health. Besides body fat percentage which is prime for many users, the BIA sensor also measures other health-centric metrics such as:

  • Weight (Entered Manually)
  • Skeletal Muscle
  • Fat Mass
  • Body Fat
  • Body Mass Index (BMI)
  • Body Water
  • Basal Metabolic Rate (BMR)

As is evident, the Galaxy Watch 4’s body composition sensor provides an almost complete picture of a person’s body health along with other finer details. Individuals invested in losing weight or making themselves fitter can easily look up their Body fat and Fat Mass to stay healthy. If you’re the sort who has calories as prime key, the BMR result also shows you your basal calories so you can build upon them. Whereas, the BMI result compares weight against height and as mentioned, you need to have a weighing scale for that.

However, do keep in mind that Samsung has made people aware that the Galaxy Watch 4’s BIA sensor is not intended to detect, diagnose, or treat any medical conditions or illnesses. So while you can go ahead and measure your body composition, do not expect the watch to have pinpoint accuracy. We will talk more about that below.

Things to Keep in Mind Before Measuring Your Body Composition Through the Galaxy Watch 4

When measuring your body composition metrics among other things, there are a few things that Samsung has declared users should keep in mind.

For starters, the company has recommended users measure their body composition at the same time of the day and in the morning to get accurate results. Before you go on placing your fingers, make sure you are on an empty stomach and have gone to the bathroom once. Users coming off a heavy workout or even a sauna should first cool off as high body temperature can throw off your readings.

Note: If you have a cardiac pacemaker or any other electronic device inside your body, do not use the Watch 4’s BIA sensor since there is a chance of malfunction.

Women are not advised to measure their body composition while having their menstrual period. Moreover, while pregnant women can use the Galaxy Watch 4’s BIA sensor, they should steer clear of it because of the chances of inaccuracy. Also, be sure to remove any metal objects like rings and jewellery from your body before you begin.

While these requirements do sound annoying, remember that measuring finer details of your body composition is a complicated process, and try crossing these off as necessary needs. However, the good news is that actually using the BIA sensor is a lot easier than it sounds and only has a few position pointers you should keep in mind. Keep reading to learn how to measure your body composition using the Galaxy Watch 4.

How to Measure Your Body Composition with the Samsung Galaxy Watch 4

Measuring your body composition using the Watch 4’s BIA sensor and is easy and only takes under 15 seconds. However, before we teach you how to do that, make sure the points below are clear.

  • Make sure both your arms are to your chest level so your armpits are open and not touching your body.
  • Make sure the two fingers that touch the buttons do not touch each other or the watch.
  • Do not move when the measurement is being taken.
  • If you’re having problems with the measurement, moisturize your fingers with lotion.
  • Wipe the back of your watch before measuring for the best results.

With that in mind, follow the steps below.

1. With the watch on your wrist, unlock it and make your way to Samsung Health from the app list.

Samsung Health

2. Tap Body Composition to get to it.

Body composition galaxy watch 4

3. Tap Measure to begin the process.

Measure button

4. The watch will require you to input your weight, height, and gender so do so.

Current weight

5. Place your middle and ring fingers on the Home and Back keys to begin.

middle and ring finger sensor galaxy watch 4

6. Do not move and wait for 15 seconds until the results are displayed.

Once done, you can read the results and infer your conclusions accordingly. These results can serve as a benchmark and you can continue to retake the measurement if you wish.

How Accurate Is It?

While body compositions scales, in general, have a 1 to 2% of error rate, the Samsung Galaxy Watch 4’s BIA sensor is pretty accurate. As someone who has used Mi’s Body Composition Scale for the better part of a year, I decided to measure my body composition across both the devices and cross-compare. Wiping both the devices clean, I measured my body composition twice to get an accurate list of results.

  • How to Use Galaxy Watch 4’s Body Composition Feature and Is It Accurate?

As you can deduce yourselves, the results overlap each other while remaining in the same ballpark. Metrics like my body fat and fat mass overlap each other with the Galaxy Watch 4’s BIA sensor showing an increased difference of over 5%. The smartwatch also places my Basal metabolic rate at 1539 calories compared to Mi’s scale of 1736. A difference of almost 200 calories while not a big one is still a difference. My BMI remains consistent but that’s because of the calculation made while comparing my height and weight.

From my own composition experience I can infer that while the Galaxy Watch 4’s BIA sensor is fairly accurate at pointing out my body’s metrics, it is not suitable to be used to get the exact specifics. So if you’re a smartwatch user trying to leverage this new BIA sensor, make sure you use it only periodically instead of making this a daily regimen. Moreover, since the Samsung Galaxy Watch 4 is the new kid on the block, it is natural that it will receive many updates over time which might add tweaks and improvements to the BIA sensor’s software and to Samsung’s algorithm. However, as things, for now, I will alternate between the Mi scale and watch while only using the latter as a reference instead of concrete proof.

Frequently Asked Questions (F.A.Q)

1. Does the Galaxy Watch 4 BIA Sensor Measure Weight?

As discussed above, no it does not. The Galaxy Watch 4’s sensor requires users to input their weight each time they are measuring their body composition. This is due to Samsung’s own algorithms which run your manually entered weight against the data to give you an accurate result.

2. Does the Body Composition Feature Harm My Body?

While you’re right in being careful about microcurrents going through your body, rest assured the BIA sensor will not harm your body. The voltage that runs across your body is very minor in nature to the point you won’t even feel it. However, as mentioned above, individuals with cardiac pacemakers or other electronic equipment should hold off on using the BIA sensor and instead refer to their cardiologist first.

3. Should I Measure My Body Composition Regularly?

It is not advised you measure your body composition regularly. Since overall body composition is something that takes weeks to change, daily measurements will only confuse your long-term goals. Moreover, other factors like the time of the day and your hydration state might also influence the results thereby making them unreliable.

4. Will the Galaxy Watch 4 BIA Sensor Work with Third-Party Apps?

From what we have gathered right now, no it will not. Since the Galaxy Watch 4’s body composition sensor is proprietary, it requires the official Samsung Health app to function. Any attempts at using third-party apps for the BIA sensor put this at your risk and might cause damage to the hardware.

5. Should Kids Use the Galaxy Watch 4’s Body Composition?

While there is a low chance of children being harmed by a body analysis, it is not recommended they use the Galaxy Watch 4’s BIA sensor to measure their body composition. To clarify this point further, Samsung has even said that readings for individuals under 20 years of age might not be accurate.

6. Can Pregnant Women Measure Their Body Composition?

Yes, they can but perhaps they shouldn’t. Attempting to measure your body composition while pregnant will not provide you with accurate results as there are other factors involved.

Use Galaxy Watch 4’s Body Composition Feature to Its Full Extent

We hope the above guide proves useful in breaking down the Samsung Galaxy Watch 4’s body composition sensor. While you can go ahead and buy the Galaxy Watch 4, these best smartwatches can take your fancy if Samsung isn’t an option. Mi users looking for something good and affordable can go for the Mi Smart Band 6 which is now available worldwide. Have any more questions about the Galaxy Watch 4? Ask them in the comments below.