Fitness Friday: Activity Tracker 411

Happy Friday, everyone! I hope you all had a Merry Christmas! With the New Year right around the corner, lots of people are gearing up for resolutions and goals, many of which involve exercising more, eating better and losing weight. Perhaps some of you got a new activity tracker for Christmas. If you did, or if you already had one, today’s post will tell you how accurate those trackers are and how you can get the most out of yours.

Last week the American Council on Exercise released the results from a study it sponsored that looked at how accurate four different brands of activity trackers are. The brands they studied were the Jawbone Up, the Nike Fuelband, the Fitbit Ultra and the Adidas MiCoach. The study, conducted at the University of Wisconsin, Lacrosse’s Exercise Physiology lab, compared data from each tracker against data gathered from a medical-grade metabolic analyzer and hand-counted steps (considered to be the only truly accurate method of step-counting).

The study’s findings were a bit eye-opening to me.  The researchers found that, regardless of brand, the devices did a pretty good job of tracking steps when participants were running, walking or using an elliptical machine. They didn’t fare very well, however, when participants were doing sports-related exercises (ladder drills, shooting free throws, doing lay-ups, etc.)

Disappointingly, another area of significant inaccuracy was in the calorie-estimating department. Depending on the activity, the trackers either over-estimated or under-estimated calorie burn by dozens of calories.  They were all fairly close when subjects were walking, over-estimating by only a few calories for 20 minutes of activity, but when the pace quickened to a jog, the trackers over-estimated calories by anywhere from 20 to nearly 50 calories.  When participants used the elliptical machine or did agility drills, however, the trackers underestimated calories somewhat.  Of the four brands tested, the FitBit Ultra performed the best in terms of accuracy of both steps tracked and calories burned, but only by a small margin.

The take-away here is that you should definitely not use your device to determine how many leftover Christmas cookies you can have. What these trackers are very good for, is motivating people to simply be more active. Earlier studies found that individuals who wear activity trackers are about 30 percent more active than those who don’t, and that’s a huge deal!

What’s great about that is you don’t even have to spend the money on a wearable device if you have a smart phone – you can download an app for a fraction of the cost, or even for free, that will serve the same basic function. These apps are even less accurate than the wearable devices, but they should be consistent enough from day to day to inspire users to get in more steps and other activity.

If gadgets and gear inspire, you though, and you’re thinking of buying a tracker to help boost your fitness resolve in 2015, I highly encourage it! Just remember that the calorie data you get from it won’t be entirely accurate, so you shouldn’t use it to  try to “balance” calories consumed. In fact, I recommend you don’t factor exercise calories into the weight loss equation at all. (I explain why in detail in my weight loss book, due for publication mid-2015.)

I’ll leave you with one last tip: Possibly the best way to use a tracker is as part of a group. I highly recommend that you download and use the app associated with your device and add as many friends to your network as you can. By making your activity results semi-public, you’ll have an added layer of accountability and incentive to keep moving!

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