Can We Rely on Activity trackers?

Updated: Aug 12, 2021

Activity trackers. Love them. Tiny good-looking wearables, that track and store data about your activity levels per day. There are hundreds. From thin bracelets with no screen to small smartphones in the shape of a watch, they are everywhere. Designed to fulfill more than what customers could possibly desire. From just simple step counting to GPS tracking and even taking phone calls and paying through them. A true health assistant that lives on your wrist. But how good are they really? Let’s find out.


Well, I do like activity trackers to be honest. It is nice to know how many steps I have done for the day. Or have statistics for the entire week. to know if I had some activity every hour. It is cool to go for a run without a phone and know exactly how many kilometers I ran and where. Having a constant heart rate monitor is quite useful sometimes too. And yes, even if I don’t use the rest of the features, I guess a lot of people are finding some of them useful.


There are specific ones that are made for athletes and designed to measure the HRV (heart rate variability). This is simply the variation in the time interval between consecutive heartbeats in milliseconds. In other words, it is the rate at which your heart slows down or speeds up itself, according to the demand. For example: if you did not sleep very well, your heart will struggle to go back to normal after a spike in your pulse, stating that your HRV is high and you should probably not engage in a very intense activity today, because it won’t be as effective.


This is a pretty useful tool to have, especially if you are an athlete that wants to get the most performance possible and adjust their lifestyle for more. However, for most of us, the normal people, that just want to be a bit fitter or healthier, a lot of those tools are highly overrated, and in some cases even detrimental.


‘’Man, did you see the latest apple watch? It can scan your brain every hour and tell you what and how much you should eat.’’

Right, I exaggerated a bit. But the thing is, people are really counting a lot on those devices. In fact, more than they really should.


Step count.

See, knowing how many steps you have done is a useful tool that can help you gain awareness of how much you actually move throughout the day. On the other hand, it can trick people into thinking that the more steps they do, the faster they will burn the body fats. It is not only a wrong statement but also a scary place to be. I have seen people punishing themselves for not achieving the step count, by starving themselves. Not a good idea.


Calories burned.

When I first got my Fitbit, I took my measurements and the app estimated that I should burn 3200 calories per day to lose weight. That was set as a goal, and every time I achieved it, I was rewarded with a funny empowering animation. That is great, but how the hell that bracelet knew how many calories I burned. Sometimes I would achieve that at around midday. Before my training, before the 30 minutes biking back from work, etc.… So, understanding the law of thermodynamics and being told that I am probably burning 5000 calories per day, I assumed that I should eat more. Well, I am glad that I couldn’t eat 5000 calories per day, but I am also glad that I did not put on a lot of fat either. Because I genuinely thought that I should eat more.


This is not a good tool for measuring the amount of burned calories. Bracelets can’t tell how your metabolism works. It does its calculations, based on the measurements and the goals you previously set, and the amount of activity you do. That is never going to be accurate and can lead you to bad behavior with movement and food.


Heart rate.

Being able to constantly monitor your heartbeats and sleep is pretty cool and can be a useful tool. The problem is when the app has those heart rate zones. Depending on the heart rate, the app will tell you if you are in the cardio zone, fat burning zone, etc… Cool, so the more time I spend in the fat-burning zone, the faster I will get rid of my love handles. Absolutely wrong. The fat-burning zone is somewhere between 90 to 120 beats per minute. That is a cardio activity. That is going to slow down your metabolism and make you more efficient with calories. It is not ideal to follow that guide.


The truth is that those measurements can and should only be useful tools for gaining awareness.

For instance, Let’s say that your goal is 10 000 steps per day. You can see the data for the whole week and identify when you walked less and why. It can be a motivator for you to get you up and going. It can make your progress visible and that can be helpful for some people. Maybe your goal is 10 000 steps, but you can do only 2000 for now. Being able to see the numbers can help you to gradually increase the activity.


Seeing how many calories you burn per day can be also useful, for gradually increasing your activity. If the app says you burned 1000 calories today, maybe your goal for tomorrow is to burn 100 more.


A heart rate monitor is quite useful if you want to see how fast you can recover and thus try to improve it. If your heart has gone up to 160 beats per second after a set of 10 burpees, your goal is to bring it down to 80 for instance as fast as possible. That can help you focus more. Or teach you different breathing methods.


The goal is to use those tools to gain awareness of how our body works. Not to rely on and blindly follow them.


For example, with my girlfriend, we like to walk outside. It helps us relax, breathe fresh air, connect better, etc… We like to play a little game though. We check how many steps I currently have logged on my phone, before the walk. After the walk, we will try to guess and bet how much we have done. Whoever is close, gets something. It is a silly game, but the more we do it, the better we become. That helps us to get the awareness of how much activity we have. So even without the phone, we would know how many steps we have taken. So, the phone is just a tool that we use. Obviously, it can’t be perfectly accurate, and it does not need to be.


Speaking of which reminds me of the fact that every phone these days has a step counter, or if not, you can download one.


You don’t need to spend your money on fancy bracelets. And if you do want one, get the cheap ones. You don’t need much. Most of them have step counters and heart rate monitors. Maybe a watch could be useful too. Whatever it is, will do the same job.


How you use the activity tracker is your responsibility. You can choose to use the hammer to hurt yourself, or to build something. Be smarter than your smartwatch.

7 views0 comments