Garmin Forerunner 305

Full Tips For Garmin Forerunner 305

By Pazman/Rainmaker

Forerunner Garmin GPS

Garmin forerunner 305, or garmin forerunner 205 primarily used for running, or biking for a secondary usage. The main reason for users used it as the instantaneous readout of distance, running pace and heart rate, the latter needed for the speed work want to do the running season. The core functionality (distance and heart rate monitoring) works perfectly. There’s none of the signal drops like other heart monitors. The initial acquisition of the satellites can be quirky and can take some time. The accuracy (according to the readout) is +/- 25ft, depending on how many satellites can be found.

The only disappointment is the point-in-time (instantaneous) pace measurement. It varies wildly during a run. The swings as big as +/- 3 minutes/mile. For a marathoner, pace is fairly consistent during a run is one want to know. I just looked at your run today, and according to the data the first mile varied from 5:57/mile to 12:06 mile. I suspect the problem is either in the averaging algorithm (too short a distance?), or in the uncertainty that results from different satellites coming in and out of view. The variations seem to get worse under tree cover compared with an open area. Luckily there’s a lap-average pace that can be presented, and at least that value is useful and more accurate. The bottom line is that you can’t look at the watch and say “right now I’m running 9 mins/mile”. There is the ability to specify a pace smoothing factor, but I have it maxed out and still see the variations. The elevation readout also seems inaccurate, but that isn’t important to me.

Garmin Forerunner 305 Data Treatment

Upload of workout data from the Garmin Forerunner 305 to the PC software (Training Center) is transparent. The PC software is very good for presenting time/distance/pace/heart rate/calorie data. However the maps it shows are very crude. I’ve worked a bit with one of the online, subscription services (Motion Based). That looks really good and provides some additional functionality beyond the included Training Center software, although I still haven’t decided if it’s worth the $$$ yet for long-term data storage. Motion Based allows export to Google Earth, and it’s tremendously cool to see your running path superimposed on a satellite image. You can recharge the unit through the USB port on your computer, although it’s slower than using the dedicated recharge. Updates and Downloads Software for Garmin Forerunner 305

Google Earth for Garmin Forerunner 305

Ok, the downloadable version of Google Earth rocks. While not as useful for directly viewing athletic data (such as your HR), it’s great for looking at you’re routes. You can easily export directly from either Motion Based or Sport Tracks to Google Earth and have it automatically open up for you. It’s like having the online Google Earth offline. You can cache up to 2GB of imagery on your local machine for review offline. I downloaded a small utility for pre-caching a specific area (such as all of DC) so I could look at stuff on the plane if I wanted to.

The downloadable Google Earth is free. You can pay $20 extra per year if you want the ability to directly connect your Garmin to it (instead of routing via either MB or Sport Tracks). I haven’t found a reason to pay the extra $20 yet. Below is a screen shot of it. It will also do flyovers of your route if you click the play button on the left hand side. The cool part is tons of people have uploaded KML files for just about everything. For example, I found a .zip file with about 100 DC bike routes in KML format to load into Google Earth. From there I can easily examine potential bike routes (or any route).

Garmin Forerunner 305 On the run

Like most running watches (GPS or foot pod), it will give you your pace as you go along. If you’re in ‘run’ mode, it will show it to you in minutes per mile, if you’re in bike mode it will show it to you in MPH. These are obviously all changeable and switch able to metric. When in operation, the watch gets divided up into three or four quadrants to display information (depending on how you configure it). I ran with pace, total time, total distance.

The pace meter overall does a good job in most conditions. I have found cases over the past few months where the Garmin has issues. For example – trail running with MANY quick switchbacks or heavy trees. It does track your general path, but quick switchbacks will get ‘lost’.

If it does temporarily ‘lose you’, it will recalculate your pace/distance based on last known location. Meaning if you’re traveling in a straight line (like a street) and you lose signal – it figures out where you most likely went and interpolates. You generally don’t notice this on the watch itself unless your constantly looking at it – and the software later on simply does math between the two points.

One cool thing I haven’t tried yet is the ability to race against yourself on a known course. It will apparently show you how far ahead or behind you are of yourself. Kinda cool. You can also set up courses where you specify the distance/pace and it will beep if you’re too far ahead behind. There’s a million variations of this you can apparently do. In general, it’s all about RTFM (Read the Fun Manual).

Garmin Forerunner 305 On the bike

It is sooo much nicer to have the Portable GPS Systems on a bike compared to a normal bike distance computer. Not at all because I want to see a map during the bike ride itself – nope, it’s all about the post-ride fun. This is because you get to overlay it onto Virtual Earth afterwards and see yourself covering serious distance – it really helps to bring it all into perspective.

One neat part though was being able to easily split up my ride based on different parts of the ‘course’. For example – the first few miles of many of my long rides are getting out of the city streets and onto established trails – these first few miles are usually considerably slower due to stoplights. Being able to break my ride into ‘warm-up’ and ‘workout’ is fairly helpful when evaluating my pacing over time (months). Like the Polar, the Garmin also shows altitude gained. It’s pretty amazing to look at total ascent/decent, which includes the tons of times you go up and down small hills. Beware though that it’s best to use some of the altitude correction features available in software as the native altitude sensors within the device are a bit ‘liberal’ (I could go into a long complex explanation as to why…but I’ll save that for now).

One other cool thing it does that’s particular useful for biking is it also calculates your ‘moving speed’ – as opposed to just your average speed. As you’ll note if you look at my graph, I hit every red stoplight in Alexandria and Arlington on Saturday. I spent 20 minutes at stoplights (yes, 20 freakin minutes).

Garmin Forerunner 305 In the woods

I was up in Shenandoah National Park earlier this summer, and did a very short (1.4mile) trail hike. It was basically through wooded terrain down a ravine following a waterfall. The Garmin stayed on track and was dead on with the measurements compared to what the National Park Service said the length would be. I also never lost signal in the woods. Granted, these were wimpy east coast woods without tall pine trees – but a good sign nonetheless. It gave us the same distance going up as when we went down. That’s good. However, I have found that running (or even worse – mountain biking) with tons of switchbacks tends to cause device confusion. You can increase the frequency of position updating – but at a serious hit to your battery. Given how rare I use it in deep trees, I’m not worried.

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