ARE WEARBLES Worth IT?

The wearable tech industry is valued at approximately $180billion, and claims from manufactures state that devices such as smart watches and rings provide valuable insights into health and fitness and can even provide a platform for behaviour change in public health. The first FitBit was release about 15 years ago, so surely we should be seeing some of the fruits of these benefits. Let's see what's been happening in to out health and fitness trends as they relate to wearable tech.

Let's look at some of the key markers and how much error is involved. When we talk about error, I like to imagine it like a clothing size, as in you'd be annoyed if it was incorrect in either direction. An margin of error of 20% too small OR too big is still a bad outcome. If you think of this when measuring your health, it becomes particularly more significant.

We'll mention the average margin of error for most devices as well as any standout performers.

Resting Heart Rate

A reasonably good indicator of heart health . A good baseline indicator of relative fitness.

MARGIN OF ERROR: 3-5%

This is pretty good and would be quite acceptable for most people. No real standout performers as HR tech has been around for a long time now.

Workout Heart Rate

Used for measuring exercise intensity, capacity, and as part of the VO2 Max formula.

MARGIN OF ERROR: 10-15%

Not great. Interestingly the margin of error gets greater as intensity increases due to movement variances and heat/sweat disruptions. Chest straps and blood pressure cuffs are far more accurate than watches or rings.

Calorie Counting

Useful when food and activity balance needs to be monitored for body composition or performance goals.

MARGIN OF ERROR: 30-40%

Atrocious. Imagine being told the pants you bought online were a size 12 but then were a size 6 when they arrived? You'd send them back and ask for a new pair, BUT they could arrive the next time as a size 16! You'd be furious.

Step Counting

Helpful as a basic measure of daily physical activity.

MARGIN OF ERROR: <5% for walking but increases as intensity increases. Still less than 10% though.

Pretty good. A nice way to check your daily movement targets.

Sleep

Useful for understanding sleep trends and patterns which may impact health, physical and cognitive performance.

MARGIN OF ERROR: 10-25%

Pretty ordinary. While most devices are good at detecting when people are asleep, they're not great at measuring the specifics like wakefulness and REM sleep.

There are some wearable which have been designed to do well in certain areas and have higher accuracy. The Whoop Band for example is more accurate at measuring sleep parameters, however restfulness and sleep quality are HIGHLY influenced by our beliefs. That is they have a very high placebo effect. If you believe you had a good sleep, you will feel more rested, alert and performance will be higher. The opposite is also true, if you believe you had poor sleep, you will feel drowsy, and perform worse. So having a ready sleep report might not actually be worth if it can so easily effect us. You might wake up feeling rested but see a poor sleep report and it can ruin your day!

Garmin is one of the leaders when it comes to activity and hear rate parameters and can be a useful tool for those involved in frequent and more intense activity. But like most other wearables it's not that great at tracking calories. This can be important if you use your wearable to dictate your training program, recovery periods and nutrition. It's often better to trust how your body is feeling as opposed to what your watch is telling you.

So where to from here? If these devices are just average at tracking things and have pretty unpredictable error rates, are they worth using? The short answer is yes. Over time, the larger the collection of data you have, the more accurate your TRENDS will be. Each measurement on it's own, is not that great BUT if you take a snapshot of changes across a month, then the picture might be a little more valuable. In my opinion, the main downside of wearables is their ability to feed obsession. We are already in a culture of performance and health stress where people are searching for the next solution or fix for their problems, or the one advantage for performance, wearables create a high risk of health anxiety. Particularly when it comes to things like sleep or calories, people are prone to be fixated on the data which often leads to worse wellbeing outcomes in the long run.

The question I leave you with is, how much are you willing to trust what your body is telling you without needing to see it on a screen?

Tim Douge AEP

Exercise Physiologist, Director

Studio 99