Garmin Body Battery: Is it useful for health and fitness?

Garmin Body Battery is a Garmin function that is designed to provide insights into your energy levels and readiness for exercise. The feature is available on a number of the company’s devices and can help users exercise more effectively. But is it really a useful feature? How does it work? Let’s explain.

How it works

According to Garmin’s website, Body Battery combines heart rate variability (HRV), stress, and activity data to calculate the user’s likely energy reserves. This information is used to generate a number between 1 and 100, with 100 being the maximum energy.

The HRV is a useful measure of the dominance of the sympathetic nervous system. The sympathetic nervous system is responsible for the “fight or flight” response and is associated with increased heart rate, suppressed immunity, digestion and fear, among other things. Usually, when we exhale, we become a little more parasympathetic, which means our body relaxes slightly. This is indicated by a slight decrease in heart rate, which gives us “variability”.

If the heart rate doesn’t change as much as you exhale – if the variability is small – it indicates that the body is too stressed to calm down. This tends to correlate with physiological arousal, illness, toxicity, psychological stress, hunger, or incomplete recovery.

Stress and activity

According to Garmin, HRV data is then combined with stress. This is derived from the HRV data, but it’s possible to see how the two metrics interact in the screenshots (above). By and large, more stressful = a quickly drained battery, as you’d expect.

Activity levels can help contextualize this data. If you’ve exercised vigorously for five days in a row, you are more likely to get tired.

Sleep data also flow into your Body Battery Score. Garmin recommends that the best way to charge the battery is to sleep well while carrying the device.

It is crucial that Garmin Body Battery is based on accumulated data. If you are having a very relaxing day it will be indicated in the light of your previous activities. This is important: a night of poor sleep doesn’t mean low energy immediately. However, five nights of lack of sleep are starting to worsen!

Why Garmin Body Battery is useful

How useful is Garmin Body Battery? The answer depends very much on your personal use. Many people find that Body Battery is a fairly accurate representation of their subjective energy levels. This makes it a helpful aid in decision making.

Knowing how hard it is to exercise on any given occasion is important as it can destroy the body if you just keep asserting yourself when you are tired without giving it a chance to recover. This can lead to overtraining or under-recovery, which is considered by some to be the more accurate term.

See also: The best Garmin running watches you can buy

At the very least, adequate recovery time is required to get the best workout results. Weight training, for example, has two phases. While we are giving the growth impetus in the gym, muscles actually repair and grow during our anabolic rest period. Similar processes enable adjustments in the nervous system. Getting harder for longer isn’t always the solution.

Likewise, management of the Garmin body battery can teach better energy management in general. It can help users adopt healthy habits. As they say, what is measured improves.

Finally, with tools like Body Battery, we can spot trends. If you find that your score is consistently lower than you’d like, then you can look for ways to improve it. Perhaps you are sensitive to your phone’s blue light before bed, which decreases sleep recovery? Maybe you should give up the nightcap? These are all factors that you can potentially determine by looking at your scores.

We should also recognize the limitations of these tools. After all, the best indicator of recovery is how your own body is feeling. The best way to know whether or not to exercise on a given occasion is to just listen to what these systems are telling you!

There are many other factors that contribute to exercise readiness – factors that are impossible to measure with the Garmin Body Battery. Your body battery score may be high, but if you’ve been injured or have a migraine headache, don’t exercise.

Above all, listen to what your body is telling you about your recovery.

In addition, the body battery primarily reflects the HRV. While the score may also take into account other factors such as activity and sleep, these should already be included in your HRV.

This feature is not entirely unique either. Other devices, such as the Oura Ring 2 or the Whoop Strap, have a similar ability to measure HRV and provide a readiness value. The Oura Ring 2 probably does that even better.

In the case of the body battery, the user has to wear the device regularly even at night and only take short breaks in charging. When you stop using the tool, dotted lines appear on the graph. This shows estimated values ​​that are generated as a combination of population data and individual trends. However, if you stop wearing the watch for several hours, the score will be reset. In other words? Body battery is a commitment if you want to see the most accurate information. This will put some users off, especially those who own the bulkier Garmin products. (Personally, I have trouble sleeping with a fitness tracker other than the Apple Watch.)

None of this means that the body battery is a bad quality. only that it is not revolutionary and should not be seen as the last word on recovery.

Garmin devices with body batteries

If you’re ready to try Garmin Body Battery, you can find it on one of the following compatible devices:

Once you wear the device, it can take 5-7 days to learn your habits and adapt accordingly.