# Difference between GPS Cycling Computer and GPS Running Watch



## likeybikey (Nov 24, 2007)

Can anyone tell me the difference between a GPS cycling computer (e.g., Garmin Edge 520) and a GPS running watch (e.g., Garmin Forerunner 235) in terms of the data it records and why the running watch couldn't be used for cycling and vice versa?

I ride and run and would like to leave my phone at home and get one device that does everything. It seems like once you add "multi-sport" to the name the price goes up. All I want to do is sync with Strava and MapMyRide to see where I went, how long it took, and if I crushed any segments. I am not immediately understanding why I need "multi-sport" to record that kind of data.


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## Mudguard (Apr 14, 2009)

There's not a great deal of difference, I have the 310XT and used that for some time on my bike. But I use a 520 now with a cadence and wheel sensor. The biggest difference is the 520 has GLONASS whereas I don't think my Forerunner did, and I've paired the sensors to the 520, so I have a more accurate measurement of my ride.
And the 520 pairs with my phone and uploads as soon as I hit save, unlike the 310XT which needed a special USB dongle and needed to be within range of my laptop. The data from the 520 goes through my phone and the Garmin Connect App (which I very rarely look at) and into Strava automatically and almost instantly.
I also like the fact if I get a message of some kind on my phone, I can see it on the 520 which is mounted on my stem, same for calls. If it's important I can stop and dig my phone out of my pack, if it isn't, I ignore it and keep riding. 
But you can absolutely use the 235 if you already have one.

Edit. I have 310XT, I can never remember what it's called.


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## likeybikey (Nov 24, 2007)

Thanks, @Mudguard.

So when you used a running watch on the bike, you were able to tell Strava it was a bike ride and not a run? And vice versa if using a bike computer for running? And all the normal information appeared in Strava?

I still don't understand why "multi-sport" watches allow you to select "bicycling" or "running." Is there something they calculate that only applies to cycling or running and not both? For example, the Garmin Vivoactive 3 offers these two "modes" as well as others. (Though I'm pretty sure all I would ultimately care about is the data on Strava and MapMyRide.)


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## MSU Alum (Aug 8, 2009)

Strava allows for selection of activity on their site. Possibly, on selection of activity on the watches, it varies sample rate - higher sample rate at higher speeds.


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## Harold (Dec 23, 2003)

likeybikey said:


> I still don't understand why "multi-sport" watches allow you to select "bicycling" or "running." Is there something they calculate that only applies to cycling or running and not both? For example, the Garmin Vivoactive 3 offers these two "modes" as well as others. (Though I'm pretty sure all I would ultimately care about is the data on Strava and MapMyRide.)


The biggest difference is how the data is displayed while out on the activity, rather than the data actually recorded. I have a Forerunner 310XT (triathlon watch, though I have never done tris). In running mode, "pace" is the operative field, instead of "speed", which displays in cycling mode. Pace is stated as "minutes per mile", instead of miles per hour. Runners like to know if they're running a 6 minute mile or a 10 minute mile, and so on. Strava doesn't change the sample rate on data from watches. Strava uses the data the device provides. It massages the data from every device, but it doesn't change the sampling rate. That is set on the device itself, and the options you're given depend on the ones the device provides.

Strava and other websites make assumptions about your activity type based on the device you use, to simplify the upload process (most people use forerunners for running and edges for cycling, so this assumption works most of the time). So yeah, you have to manually change it if you are doing a nonstandard activity with a fitness GPS. If you use a more general GPS like a handheld or a Fenix or something, you'll have to do the same thing, anyway, so it's really not that big of a deal. Though it does simplify the upload process if you've told the GPS before your activity what the activity type is, assuming the GPS gives you that option.

Me, I don't like watches when I'm riding. The screen is not in a very good location for quick looks without taking a hand off the bars if you wear a watch, but that's not the biggest reason for me. For me, it's simply a comfort issue. I really don't like wrist bands. I don't like wrapping the wrist band around the bars, either. I actually got a QR adapter from Garmin for my tri watch that allowed me to snap the computer off the wrist band and snap it onto an Edge mount on the bars. Which means I can also snap my Edge 520 onto the wrist band, which I've done for hikes once or twice.

Another thing I like about using an Edge on the bike is that it fits more data fields. My Forerunner 310XT fits 3 fields per screen. The Edge 520 can fit more than twice that, with bigger text available if I use fewer screens. The two can use the same bike sensors, but the 310XT can also use running sensors (foot pod) that the Edge cannot use. I'll bet that a running-only Forerunner won't be able to use speed and cadence sensors on a bike. To use speed/cad sensors, you'll likely have to have at minimum a multisport model. A wheel sensor for speed and distance really does improve distance accuracy substantially on a mtb. It's very worthwhile, IMO, and is even more worthwhile the twistier the trails are that you're riding.


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## Le Duke (Mar 23, 2009)

GPS is GPS. There is no fundamental difference between them in terms of the data they get from birds in sky. 

They DO have the ability to collect different data via receivers, such as power meter data from a bike, recorded on a cycling-specific or multi-sport computer (in cycling mode).


Sent from my iPhone using Tapatalk


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## likeybikey (Nov 24, 2007)

Thanks, all, for the replies. The information is very helpful and makes me reassess my purchase decision.

Also, nice blog, @Harold!


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## ScaldedDogCO (Sep 22, 2016)

The 235 has a bike mode, and I've been using it for that exclusively the last couple of years, since I can no longer run. Garmin Connect and Strava both recognize a ride as a ride.

Mark

Sent from my SM-G935V using Tapatalk


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## J.B. Weld (Aug 13, 2012)

One advantage of a watch that I haven't seen mentioned is that you get heart rate data without having to wear a chest strap, if you're into that sort of thing.


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## Harold (Dec 23, 2003)

J.B. Weld said:


> One advantage of a watch that I haven't seen mentioned is that you get heart rate data without having to wear a chest strap, if you're into that sort of thing.


Not all watches do this, which is why I didn't mention it. Also goes without saying, if you wrap it around the bars, the built-in HRM doesn't work.

Sent from my VS995 using Tapatalk


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## ScaldedDogCO (Sep 22, 2016)

The 235 does, but I don't think the optical sensor is nearly as accurate as a chest strap.

Mark

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## J.B. Weld (Aug 13, 2012)

ScaldedDogCO said:


> The 235 does, but I don't think the optical sensor is nearly as accurate as a chest strap.
> 
> Mark
> 
> Sent from my SM-G935V using Tapatalk


I skimmed a DC Rainmaker review awhile back where he compared the vivoactive, fenix and I think a few others against a 520 with chest strap and though there were a few inconsistencies I think his take was that they were pretty good overall.


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## NordieBoy (Sep 26, 2004)

My 935 with optical hr is very usable for hr if I don't feel like wearing the strap.
A couple of anomalies per ride, but nothing that skews the averages.


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