You know that thing you’ve been relying on to count your steps and measure your calories? It’s probably wrong, especially if you wear it during workouts. Plenty of studies have confirmed that your tracker is off, and it’s time we talked about it. That doesn’t mean you should stop wearing it, however. Just because it’s giving you an inaccurate measurement doesn’t mean it doesn’t have a few benefits. Read on to learn why, even though your tracker is off, it doesn’t derail your fitness goals. After all, people were getting in shape long before these things were invented.
The pros of fitness trackers
Fitness trackers run the gamut. Some simply count steps. Others measure your heart rate, sleep quality, and make complex calculations to uncover total calories burned. On the one hand, simply having this information on hand, even if slightly inaccurate, will provide some benefits. Motivation to exercise and stay on track can be hard to come by. Without a tracker, it’s easier to ignore your health away from the gym. But if you’re constantly reminded to “move more” or work towards a step count, you’re more likely to do so.
In a comprehensive study, they showed that wearing a fitness tracker sparked behavioral change through goal-setting, reward-based feedback, and even coaching. Years of best practices in psychology show that these tactics are consistent with progress. You don’t need a fitness tracker to do so, however. For example, you’ll set goals, get great coaching, and have consistent feedback with our program here at RPT. But that doesn’t mean you can’t use a little extra help, especially if you lean on technology.
The cons of fitness trackers
Unless you simply want to count steps, your fitness tracker just doesn’t do what it promises. The technology isn’t there yet, and the reliability varies greatly across people and tracking software. Something as simple as relocating the position of the device you’re wearing can shift feedback. For example, wrist-worn fitness trackers record a lot of extraneous movement (read: not steps). And what happens during high-intensity exercise without wrist movement? Your tracker doesn’t record it. It could completely ignore an hour of high-intensity training on a stationary bike.
When looking at heart rate, a more complex measurement, the risk of error increases with exercise intensity. When you get sweaty, for example, it disrupts the sensors. According to the journal Sports Medicine International Open, technology has “led to the integration of photoplethysmography (PPG) into wrist-worn devices for the purpose of estimating HR. The PPG technique is a simple non-invasive optical method that detects beat-to-beat pulsatile changes in blood flow.” During rest, your tracker will probably do a decent job at measuring your heart rate. But if you ratchet up the intensity, it might not record your heart rate at all.
The researchers tested this on an Apple Watch with walking, jogging, and running and found that validity dropped significantly as exercisers approached a run. Fortunately, it’s more likely to underestimate your heart rate than overestimate it. So you might be working harder than you think. But that could be bad in some cases, especially in those with heart conditions.
Finally, there’s one thing in particular about trackers our members should be particularly concerned with – how they work with resistance training. At RPT, we always incorporate strength training as part of a well-rounded exercise program. If your time at the gym is spent lifting weights, you’re going to want a tracker that measures activity accordingly. Unfortunately, that’s proven virtually impossible with commonplace technology.
Researchers out of Iowa State University’s Department of Kinesiology found that across six different trackers – Jawbone, FitBit, Nike+ FuelBand, BodyMedia Core, Misfit Shine, and Actigraph GT3X – error rates for resistance training were the highest. What’s even worse, they were wrong in both directions. So, if you only rely on your tracker, you probably won’t get as good of a workout as you think.
So what do you do about it?
This doesn’t mean you should throw your tracker in the trash. After all, if the reminders to exercise help, that’s a positive. Just don’t rely on it to be an accurate measurement of your activity. Obsessing over the numbers might do more harm than good. Instead, stay consistent. Set goals that don’t involve your step count, like fit into your new jeans or be able to pick your grandkid up without pain. Get a real coach who can provide actual feedback, not based on an algorithm. Above all, build a lifestyle that keeps you moving consistently and pain-free.
If you want help developing a plan, get in touch! I’d love to sit down with you to set some of those goals. Set up a success session, or take advantage of a free trial week to get started on the right foot.
Hit reply or call/text 757-589-7028, and we’ll connect for a 5-minute call to learn all the details. Our free, one-on-one consultation can help you make a decision on the best way to move forward.
Detric Smith, CSCS, ACSM EP-C, Precision Nutrition Level 1