Consumer Reports took six popular trackers for a whirl and found some better than others at helping you reach your exercise goals.
Joseph Jose never leaves home without his activity tracker. He says the results have been eye-opening.
"What I found out is that I was actually moving a lot less than I thought I was," Jose said.
An activity tracker uses sensors to gather information about the steps you take and the calories you burn. Jose's tracker syncs to his phone or computer when he's ready to crunch the numbers.
But are activity trackers accurate? In Consumer Reports' labs, a panel of volunteers wore them on wrists, arms and clothing to find out.
The panelists walked on a treadmill, used an elliptical exerciser, climbed the stairs and picked up toys, crossing the room to toss them in a bucket.
"We compared our step-count against the trackers', and all of the devices did well at counting steps," said Nicole Sarrubbo, Consumer Reports.
Next, the metabolic analyzer was used to measure the calories each panelist burned. Some of the activity trackers proved better than others at counting calories.
"Three of the trackers show how you're doing while you're exercising, and most of the panelists said they really like that feature," said Sarrubbo.
One that gives instant encouragement is the Fitbit One. The taller the flower, the more you've moved. It earned top ratings and costs $100.
As for Jose, his tracker has helped him shed 40 pounds and counting.
And another bonus - the Fitbit One lets you track the calories you eat and how well you sleep. But Consumer Reports has one caution - not all of these fitness gadgets sync with every type of smart phone or computer, so check before you buy.
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