So, its my daughter’s 18th birthday last week and I gave her a new Garmin Forerunner 10 for running and hiking. We decided to do a little test while we were talking about all the colleges she is applying to: Northeastern, UCLA, Vanderbilt, Chapman, University of Arizona and a few others that I can’t remember.
THE TEST
We used a highway wheel measuring device to measure off a popular running and hiking
The way all marathon and Olympic courses get certified for distance.
route near downtown Bozeman and it measured 3.55 miles.
I’ve been using a Suunto Ambit 2S recently and she had her new Forerunner 10, so we grabbed satellites, both in under 15 seconds I might add, and took off. I also had my iPhone with a popular run/walk app on it for good measure.
So, what was the result? At the end of the 3.55 miles the Suunto Ambit 2S registered 3.54, impressive only 1/100th of a mile off. The Garmin Forerunner 10 measured 3.53 miles, still impressive as it was only 2/100th’s off of wheel measurement. Between 3/10ths of 1% and .55 of 1 percent of dead accurate.
So, what about the iPhone? It registered 3.24, so it was .26 of one mile, that is over 1/4 mile off of accurate. In percentage terms it was 7.3% off of being accurate.
Here is the Ambit 2S distance after downloading to Suunto Movescount.
Garmin Forerunner 10 was only 1/100th of a mile different from Suunto Ambit 2S
WHAT DOES ALL THIS MEAN?
There are millions of people, in the USA alone, that use their iPhones for fitness. The problem is iPhone can’t fit the GPS hardware that it takes to produce accurate GPS readings the way a watch can, the receiver just can’t be made large enough and fit in all the voice and data priority stuff. Assuming that an iPhone, or any Smartphone, is a do-all device is a bad assumption.
So, now some manufacturers are out racing to create watches that are dummy head units that receive all of their data from ……. you guessed it, a Smartphone. No matter how good an app is the data it produces is only going to be as good as the hardware for accuracy purposes.
THE POINT
Garmin, Suunto and other GPS watch manufacturers make devices solely for the purpose of accurately measuring heart rate, pacing, distance, it is not a secondary purpose. For phone manufacturers fitness was like a 5th, 6th, 7th or lower primary purpose because they are focused on voice, data, cameras and all the hardware it takes to make all that fly.
If you are even remotely serious about accurate data for fitness then you are wasting your time with a Smartphone, unless it is for the purpose of obtaining heart rate data. There are also a few cycling products that use speed and cadence sensors that are accurate on distance because they are counting measured wheel revolutions.
Of course, if you are a more casual user and fairly large inaccuracies on distance, and therefore pace, don’t bother you than by all means use them.
We realize that for many, understanding this stuff can get a bit complicated but you can rest assured that if something isn’t accurate or has a questionable reputation then we don’t carry it over at the Heart Rate Watch Company‘s website.
What has defined us over the years has been what we have decided not to carry, so any product that relies upon iPhone’s GPS hardware to accurately measure distance is out in my book. There are tons more of these types of products coming out in the future so now the buyer has to beware, unless they are getting good advice from knowledgeable parties.
The bottomline is that you can have the best app in the world but if the hardware processing that data is inadequate it is still “garbage in, garbage out”.
OUR ADVICE
If you run, bike, ski or do anything outdoors then get a good GPS watch. If all you want is basic heart rate via your iPhone then get a Bluetooth Smart strap and an app, but using iPhone as a surrogate for a GPS watch for both heart rate, pacing and distance data is a greater fool’s game and we have proven that with our testing.
iPhone works just fine for heart rate because the strap and transmitter hardware are generally made by companies, like Polar, and the apps processing heart rate information doesn’t require that iPhone have any significant changes in hardware, like GPS does.
–Rusty Squire, rsquire@heartratewatchcompany.com, copyright 2013
