By Philipp Laage
Munich (dpa) – Fitness trackers and apps let exercise fanatics keep minute detail of a myriad of factors – distance, time, speed – right on one’s wrist or smartphone. But be careful not to blindly follow the numbers.
The services trade on their ability to provide specifics – a trend known as the quantified self – which people use to improve their lifestyle.
To that end, smartphones come packed with trackers. There are also new armband fitness trackers, like Jawbone Up from Nike or the Fitbit Flex. Most are advanced forms of pedometers, relying on hyper-sensitive gyroscopes, says Gunnar Troitsch of German computer magazine Chip. Smartphones have the extra advantage of being able to pull in satellite-navigation data and mobile signals.
”That allows activities to be presented upon interactive maps, for people to work through training plans and for direct interaction with the owner,” says Troitsch.
Some of the best-known apps are MotoActv, Runkeeper, Runmeter, Runtastic or – especially for mountain bikers and bicycle racers – B.iCycle. All track improvements as well as areas where performance could be better.
Many of these are packaged with additional apps to help users evaluate the data. A lot of other apps – My FitnessPal, for example – can grab the data from the trackers, says Troitsch, since a lot of them work on identical principles.
”They are a little different in terms of the way they transmit data to a smartphone or computer,” he says. Some use Bluetooth, others wi-fi. Some require a cable or a USB connection.
Experts say most of the trackers are little more than intelligent acceleration meters, but there are exceptions, like the Withings Pulse, which also measures pulse rates.
Smartphones have an advantage in accessing more concrete data.
”The GPS is a major help,” they say. If the app is told which sport is being practiced, then the apps can provide even more specific feedback.
Fitness trackers can cost 100 euros (132 dollars) and upwards, but most apps are free or very cheap. Troitsch still sees advantages to the trackers, noting that they are smaller and lighter and their batteries can last up to two weeks, unlike the two days most smartphones offer.
”On top of that, smartphones are much more sensitive to the surroundings, especially with rain or rugged terrain,” he says.
But some question the apps’ use. They won’t help with weight loss or flexibility, however they can be a good complement to a proper workout programme, says Urs-Vito Albrecht, a medical information scientist at the Hannover Medical School in Germany.
But they’re not so good at telling people when they’re making mistakes. ”Catching those, like a human training partner or trainer would is beyond an app.” Nor will they replace medical examinations: those about to embark on sports for the first time in a long time owe it to themselves to see a doctor first.