Brian's Brain

Any of you who might be following my personal Twitter feed or Facebook page might already know, I've significantly ramped back up my mostly-trail running in recent months after several years' worth of comparative lethargy. My primary motivation, aside from the fear of an expanding waistline and the stunning summertime Sierra landscapes, are my newfound friends in the Truckee Running Club. And through their influence, I've acquired one of the most rewarding tech toys ever to come into my possession, Garmin's Forerunner 405 GPS watch:

Regular readers know that location-based services, enabled by the growing pervasiveness of cost-effective, compact, power-thrifty and accurate GPS hardware, are very much on my radar screen nowadays. And the Forerunner 405 perfectly exemplifies this trend. Strictly speaking, right now I'm using the 'CX' version of the unit, which estimates calories burned during a workout:

But two days after receiving my review unit from Garmin, I placed an order for my very own non-CX variant from Amazon...indicative of my enthusiasm for the device, I don't think I've ever before bought a product prior to the review period being over, far from only two days into it! Let me hit up the background for my purchase haste up-front, since you have a few days left to follow in my footsteps. If you order a Forerunner 405 or 405CX from Amazon by the end of June, you qualify for a $50 rebate. Plus, Amazon and Garmin toss in a cardio-only (no-GPS) Forerunner 50 for free:

I was originally going to turn around and re-sell the Forerunner 50 on eBay in order to put a bit more cash back in my pocket, but I decided to hold onto the watch for battery-life reasons. I'll explain why in more detail in a bit.

Garmin's made impressive form factor reductions in its running-tailored watches in a relatively short period of time. The Forerunner 405 was introduced at the January 2008 Consumer Electronics Show; the calorie-counting 405CX derivative showed up just a few months ago. Now take a look at the Forerunner 305, both standalone and on a model's wrist, which many of my friends own and which Garmin unveiled in March of 2007:

And one of my friends still totes the even larger Forerunner 301, which dates from the January 2005 CES:

The Forerunner 405 contains an embedded battery and employs a clip-based recharging setup. Garmin also bundles a heart monitor in the kit, which communicates with the watch via the vendor-interoperable '+' variant of the ANT wireless PAN protocol developed by Dynastream Innovations. Similarly, after your workout is complete, you place the watch in close proximity to the also-included ANT-based USB transceiver plugged into a Mac or Windows system, and the data automatically transfers to the computer and from there to your account on the MyGarmin website.

Within a minute (and often much faster than this), the Forerunner 405CX snags sufficient GPS satellites' signals to triangulate location to within 30 feet, assuming it has an unobstructed view of the overhead sky, and accuracy further improves with time. It's pretty funny to hear the chorus of near-simultaneous beeps, when a group of us who've all started our Garmin watches' timers at the run's beginning subsequently pass each mile mark.

Once I've done a particular route a few times, the standalone distance measurements become decreasingly valuable, but the distance-and-time-derived pace data remains indispensable, as does the pulse rate information (both in-the-moment and after-the-fact versus-time, versus-location and versus-pace). I'd never run with a cardiac monitoring device before, and it's amazing what a few beats-per-minute difference makes in my running endurance...keeping me below, for example, my anaerobic threshold.

Garmin offers both OS X and Windows software that lets you graphically view your training session results. Additionally, I use a freeware (donations accepted) Mac software package called TrailRunner, which (among other things) superimposes your route (and therefore your moment-by-moment pace and pulse rate) info on top of imported Google Maps screenshots (map, satellite, or terrain i.e. typographical). As such, it compensates for one shortcoming of any GPS device: imprecise elevation readings.

And what if you're running on a treadmill, wherein you're staying in one place and traditional GPS measurements are therefore meaningless? In cases like these, Garmin offers several models of foot pods that attach to your shoes and, akin to the Nike+ system, use an accelerometer to measure how long your foot is on the ground, deriving distance and pace measurements from this data.

Initially, I thought that Nike+ only measured the time between shoe-to-ground impacts and therefore would be inaccurate in my case, since I tend to run mostly on trails (which are both irregular and hilly and which therefore result in an inconsistent stride). But a recent, exellent article on the Nike+ system in Wired Magazine (whose discussed concepts equally apply to Garmin's Forerunner line) set me straight:

The basic science that allowed Nike and Apple to capture this information is low tech, introduced in a 40-year-old study published by biomechanical researcher Richard Nelson at Penn State. Nelson filmed a mix of 16 freshman and varsity athletes at the university running at various speeds, on smooth and sloped surfaces. What he found was both simple and powerful—the amount of time a runner's foot is in contact with the ground is inversely proportional to how fast he's running and unaffected by slope or stride length. That means if you know how long that contact lasts, you can make a pretty good guess as to how fast the runner is going.

For multi-sport athletes, Garmin also sells a wirelessly linked cadence sensor that mounts to a bike and enables the watch to log pedaling strokes-per-minute data, too.

Are there any downsides to the Forerunner 405? A few. As long time readers already know, I'm no fan of embedded batteries that aren't easily user-replaceable. And speaking of batteries, the Forerunner 405 only delivers around 8 hours of per-charge operating life when it's in active GPS signal-acquisition mode. For most runs save, say, a half-century or longer, that's sufficient. But for 24-hour team relays, it might be a stretch (especially if you forget to shut off the timer in-between legs). The same goes for century bike rides, or for dawn-to-dusk backcountry hikes.

As such, the claimed 20-hour active-mode battery life of the upcoming Forerunner 310XT (introduced in early April and due to begin shipping next month) is appealing, as is its even slimmer form factor:

The Forerunner 310XT's 50 meter waterproof specification would be great for triathletes; not so much for me, since I regretfully don't know how to swim ;-) Anyway, neither the wireless heart monitor nor GPS acquisition capabilities work in the water, only the timer.

I also wish that, instead of using the ANT+ USB dongle, I could mate the watch to my MacBook Air via the laptop's already-present built-in Bluetooth facilities. Initial versions of the Garmin peripheral driver and application software for OS X were buggy, randomly crashing and sometimes even completely locking up the Mac. Although latest software iterations have proven to be much more stable, leveraging the mature Bluetooth ecosystem would seemingly be a preferable approach. I'll be curious to see, therefore, how long Garmin continues to employ ANT+, given that the Bluetooth Low Energy specification is due to be finalized by the end of this year.