Hello, welcome to the Weekly Mailbag. I'm Ray, from DCRainmaker. com. If you've ever searched for reviews on sports technology - you've probably come across my site. I write about my triathlon/running training in general, along with sports technology and whatever else seems interesting to me. I started the Weekly Mailbag series earlier this spring as an opportunity to share some of the answers of the many e-mailed questions I get each week.

If you enjoy what you find here, then feel free to click the links to find even more in depth information on each topic. And if you have any questions, you can always e-mail me directly. Thanks for reading!

This week, I’m doing something a bit different. Since the Garmin FR610 released a few weeks ago I’ve been flooded with questions from runners and triathletes alike asking how it stacks up against the very popular Garmin FR310XT. In particular, most wanted to know which watch they should choose. So I’m going to outline the key differences and which watch I’d recommend for given circumstances.

The Garmin FR610 vs FR310XT Comparison

It should be noted up-front that the FR610 is billed as a runners watch, whereas the FR310XT is distinctly a multisport device. In Garmin terms this means a few things. First up is that the FR310XT supports ‘multisport mode’, which allows one to quickly transition from swim to bike to run while having it automatically change the sport mode. It does this all while tracking the overall times as well as individual sport and even transition times. Like the rest of the running focused Garmin watches, the FR610 does not have multisport mode. In addition, the FR310XT also supports more than just running and cycling, and in the case of cycling - offers and supports more than just the absolute basics (as I’ll cover in a moment).

But, what does that all mean for folks looking to simply use it in the run leg, or are running focused? Well, as I’ve come to find out - it’s quickly becoming my standard running watch. I’ve historically used the FR310XT for all my runs, while pairing it with either the Edge 500 or Edge 800 for the bike leg. On the swim I just use a simple $20 Wal-Mart wrist stopwatch, or the waterproof non-GPS FR60 (it’s cheap!).

However, before I explain my logic of using the FR610 over the FR310XT, let’s go sport by sport through the differences.

The Swim:

This is by far the easiest section…there’s simply no comparison. The FR610 isn’t fish friendly. It’s only waterproofed to IPX7, which means it can last for 30 minutes in one meter of water. But it doesn’t mean it can hold up to the pounding of a swim stroke. Having killed a few other IPX7 rated Garmin devices, I can attest that you really don’t want to try this. However, it will still work with the swimcap method.

The clear winner here is the FR310XT which supports full waterproofing and even the semi-useful openwater swim mode.

The Bike:

While the FR610 offers a fair number of options for the majority of cyclists, it lacks one area critical for many competitive cyclists today: power meter support. This is an area that is present in the FR310XT, and has actually improved considerably since the FR310XT initially launched. For example firmware updates brought changes such as 3s and 30s rolling power, originally not in the FR310XT.

Outside of power however, the FR610 actually offers the majority of cycling data fields that you’d want to add to your screen such as speed, distance, lap averages and the like. And it also supports the GSC-10 ANT+ speed/cadence sensor, allowing you to use it indoors on a trainer to gather speed/distance, as well as monitor cadence whether indoors or outside.

One area that the FR610 doesn’t cover that the FR310XT does have though is the ability to create and follow courses. I’ve found this is typically of more interest to cyclists than runners (though runners certainly use this feature). Courses allow you to create a route on a site like MapMyRide.com and then follow a bread-crumb type trail. The FR610 doesn’t have this capability in the same way the FR310XT does, instead restricting you to only following past run routes or downloadable routes on Garmin Connect - all while leveraging the Virtual Racer feature.

Of course, the bigger question that many folks ask themselves is if they want a separate device for the bike anyway. I’ve found that a surprising number of people end up going with something like the cheaper Edge 500 on the bike, and having a separate watch for the run.

The Run:

With the run being the primary area that the FR610 is targeted at, it’s also the area that it has the most parity with the FR310XT.

In fact, when you look at the two watches feature by feature, you’ll find that they’re virtually identical on the running front.

The one major area that the FR310XT has over the FR610 is extended battery life. The FR610 is going to get you between 8 and 10 hours of activity, whereas the FR310XT will take you closer to 20 hours. This is primarily of concern to ultra runners, or folks choosing to use the FR610 on both the bike and run leg of an Ironman. It should be noted though that the FR610 does get you up to four weeks in standby watch mode, whereas the FR310XT has no such mode.

The FR610 however does have a few tricks in the bag that the FR310XT doesn’t have. For example, the FR610 includes a walk-run alerting feature that allows you to alert to run for a certain time/distance, and then walk for a certain time/distance. I’ve actually repurposed this feature for nutrition reminders, as well as some high cadence drill work on long runs. Since it has both an audible as well as vibrating alarm, I find it gets my attention pretty well and reminds me both at the start and finish of the allotted nutrition time (as opposed to a standard repeating alarm).

Additionally, the FR610 adds the Virtual Racer feature, which allows you to race against previous runs. The FR310XT only has Virtual Partner, which allows you to race against a preset time/pace goal. Finally, the FR610 contains the Training Effect calculation feature, which acts sort of like some of the different TSS type calculations to gauge and specify workout intensity.

Which watch?

So by now you may be wondering exactly which watch to choose. My recommendation varies specifically on what you intend to use it for. If you plan to just use it for the run leg - then I’d recommend the FR610. I’ve found that over the past three weeks since having the FR610 that I’ve done all my runs with it, and no longer carry my FR310XT on the runs. Thus, for runners or folks wanting it just for the run - I’d say the FR610 is the way to go.

However, if you plan to use it on both the bike and run legs (or swim leg), then I’d recommend going the route of the FR310XT instead. The FR310XT offers the longer battery life that most would need to complete an Ironman race (or an Ultra), and also offers more versatility on the bike. This is especially true for anyone using a power meter, which the FR610 doesn’t support.

Finally, many have asked what my thoughts are on a potential future FR310XT replacement. While there are certainly rumblings about a summer release from Garmin and other vendors, at this point I think that if you need a watch for this season, you should choose from those already announced. Even if a watch were to surface in the June/July timeframe, it realistically wouldn’t be widely available for another 30-60 days, putting you at the end of the triathlon season for most climates.

As always, if you have any questions on either watch - feel free to drop a question in the comments section of either the FR610 review or the FR310XT review.

Recent Mailbags:

Weekly Mailbag - April 19th, 2011:
- Bluetooth Heart Rate Strap Monitors
- ANT+ Cell Phone Client and App Options
- Review of smartphone clients

Weekly Mailbag - April 4th, 2011:
- Taking the Forerunner to the pool?
- Best bet for trail running watch with altitude?
- Auto-Pause, Running and Races (and why your distance might be short)

Weekly Mailbag - March 25th, 2011:
- Understanding Elapsed Time and Time in sport files
- Deciding between an iPhone in ANT+ case, and the Edge 800
- Garmin Futures: Vector Pedals and new version of the FR310XT

You can find all past Slowtwitch Mailbags here, and all prior ones here.

[Editor's note: our capable editor-at-large for electronics Ray Maker is the publisher of the online sports tech blog DC Rainmaker, one of the top-ranked sites by Google for extremely in-depth reviews of advanced GPS and Heart Rate Monitors for triathlon, cycling, and running.]