Garmin have long had a line of innovative and well-conceived GPS fitness monitors; the Forerunner 305 has been part of our training regime for over two years now and has seldom missed a beat. So the opportunity to try out a newer variant, the 310XT, was always going to be interesting. It had a lot to live up to!
The basic premise is familiar; it's a chunky, wrist-mounted unit with a reasonably large display that can be configured to show different readouts depending on mode or need. It's pretty much got the same frontal area of the older 305 but loses the rigid 'L' shaped extension which makes it a more comfortable fit. In technology terms the new unit uses ANT+, a Bluetooth derivative, to handle all the communications; both to the peripheral units like the heart rate strap and the GCS10 bike speed and cadence sensor as well as to the PC or Mac that's the host device. While this has meant that the charging and interface block that came with the 305 is now redundant it does mean that charging is done through a clip-on unit that feeds from a USB charger common to all the rest of the Garmin line. The charger is international and comes with various plug adapters including UK and European - great for travelling with as it can charge your iPod too!
Basic operation is as simple as it comes: fit the new-style chest strap (Garmin have taken a leaf out of the Polar book with a 'Wearlink- style' strap that's much more comfortable than the old one), turn it on and go. Well, OK - it's not quite that easy but pretty close! There are a couple of things that you'll need to do first - all are covered by the very slim Quick Start Manual in enough detail to get you configured and paired-up with the chest strap in about five minutes. And, at this point, you effectively have a slightly smaller, neater Forerunner 305. So, what's the big deal?
Well, several big deals in fact.
First, this is a fully waterproof unit and that means that taking it swimming is no longer the risk that it used to be with a 305. Not only is it fully waterproof, it's fully sealed too so when the rechargeable lithium ion battery finally calls it a day it will be a case of sending it back for a refurb - but that shouldn't be for a few years of regular use so it's about the same deal as having an iPod in that respect.
Second on the list of improvements is that the smaller body is a result of improved GPS chippery inside it - it should be quicker to locate satellites and be able to hold them better once it has locked on and you are running and riding in urban or tree-covered areas. The careful reader will note that I said 'should' - we have always had problems getting an initial GPS lock where I live despite having about 270° of clear sky outside my back door. For some reason all our GPS units; car, bike, wrist and even handheld (what do you mean, "that many?") have problems locking on and the 310XT was no different. Initial lock still takes me over a minute at home but has been much faster in other locations so I'm not going to fault the 310XT here but just make an observation that sometimes any GPS simply can't get a grip when you expect it.
Changing the interface to ANT+ is a major improvement over the 305's USB connection. I first used this with the Forerunner 50 I tested last year and the ability to have a completely automated upload with no cables, infra red interfaces or anything other than a memory stick-like dongle is just wonderful. Garmin have finally put the drivers online for the Mac so I tested both the Training Center software and their Garmin Connect online service and both worked faultlessly in an upload capacity. For some, as yet unexplained, reason it proved impossible to load a software update into the 310XT from the Mac but the process worked first time with a PC - some work is still needed on the Mac software I guess. NOTE: the ANT+ agent software needs an Intel-based Mac. Overall though, this is how fitness software should work. It's seamless and delivers all the information you want both on a PC/Mac for personal consumption or via the web for access remotely or as part of a coaching network. As with other Garmin units you can download training plans back into the 310XT and there's plenty out there (e.g. check out our 10-week duathlon training plan), or you can easily build your own as we've shown before.
Having a rechargeable battery means, pretty much by default, that the unit will have a limited capacity. However, the quoted life for the 310XT is 20 hours and in testing we saw no reason to doubt that. It's probably a bit bigger than you would want on your wrist for an Ironman-distance race but that's now a realistic option - unlike its predecessors. And you'll get data recorded every four seconds throughout that time which is pretty impressive. Oh, and did I forget to mention - having ANT+ means that if your bike is equipped with a wireless PowerTap or SRM power meter then this little beauty will capture and display that information as well? Now that's more data than you'll likely need but should you have a coach capable of analysing it all you now have nowhere at all to hide when it comes to assessing your performance.
Information while on the move has long been another Garmin feature that other brands have struggled to match. You can tailor the 310XT's display with up to four data readouts and there are up to four pages depending on the sport selected. The pages can be changed manually or programmed to scroll through - I have to say I prefer the former as, clever though auto-scroll is, it always seemed to be showing the 'wrong' page when I looked. It handles running and cycling (up to three different bikes) and a non-specific sport mode as well as being able to deal with multisport by allowing you to change between sports 'on-the-fly'. You can even create multisport workouts that handle the change automatically - you get both a beep and and buzz to let you know that you've changed mode.
The 310XT comes in two basic versions: one without an HRM strap and one with. Other than allowing people who already own a Garmin strap to avoid having to buy a second one the basic model is pretty pointless in our view. A quick Google search shows that £299.99 is an average price for the 310XT with an HRM strap, allow £65 for a footpod (not strictly necessary given that this is a GPS unit but it does give you footstrike cadence information) and £40 for a GCS10 bike speed and cadence unit and pretty much all the bases are covered. Not cheap, I'll grant you, but for a wrist-mounted unit that can cover swim, bike and run and deliver solid and reliable data from all three then it's in a class of its own. It's definitely an improvement on the old 305 and although a bit chunkier than the Forerunner 405 has the advantages of better battery life and is fully waterproof.
Tri247 says: If you want the cleverest sports watch out there bar none then it's currently the Forerunner 310XT.