Tuesday, 25 January 2011

Heart Rate Monitor


I like this thing quite a lot. I've had it for about three weeks, and have used it on 12 workouts so far. I use it primarily for running, with biking a secondary usage. The main reason I wanted it was for the instantaneous readout of distance, running pace and heart rate, the latter needed for the speed work I want to do this running season.



The core functionality (distance and heart rate monitoring) works perfectly. There's none of the signal drops I've had with other heart monitors. Once the satellites are initially acquired, I've only had one dropout when I was outside. 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. I've compared the distance measurement on the GPS with a known, measured distance on one of the trails I run on (the Chicago lakefront path). The GPS always increments a mile when I'm within 5 or 10 feet of the mile marker sign on the path. Well, I guess that's the least I should expect from a $350 GPS unit! Of course it's bigger than a normal running stopwatch, but that hasn't bothered me at all. The heart rate strap is also very comfortable and well-designed.



The display is crisp and has one outstanding feature: The information presented on the various pages can be completely user-customized. The default screen layout is rather poor, but in just a few steps I could replace it with the information I wanted to see while I run. There are almost 40 different data fields you can choose from for display. Examples: current pace, average lap pace, average run pace, heartrate, distance.



The only disappointment is the point-in-time (instantaneous) pace measurement: It varies wildly during a run. I see swings as big as +/- 3 minutes/mile. I'm a marathoner and I know my pace is fairly consistent during a run. I just looked at my 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.



Upload of workout data to the PC software (Training Center) is transparent. The PC software is very good for presenting time/distance/pace/heartrate/calorie data. However the maps it shows are very crude. I've worked a bit with one of the online, subscription services (MotionBased). 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. MotionBased 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 recharger.



I had hoped that owning this device would prove motivational for me, and indeed it has. I can't imagine running or biking without it. Updating my training log is trivial now: Plug this thing into my computer, and it's done. My hope is that a future software update will do something about the pace calculation (maybe a few additional levels of smoothing?). If so, the Forerunner 305 would earn 5 stars+++.





Positives:



Flawless heart rate sampling

Great distance measuring and lap-average pace calculation

Seamless integration with a PC

Fully-automatic training log update

User-customizable display





Negatives;



Wildly-varying pace readout. Garmin Forerunner 305 GPS Receiver With Heart Rate Monitor

With a few one-star reviews, I was a bit hesitant to order this. Now, after two weeks of use (10 runs of 2 to 2.5 miles each), I have no regrets with the purchase whatsoever.



I haven't had any of the problems reported by any of the one-star reviewers. It syncs to the satellite in a reasonable* amount of time, seems to track my pace very well, tracks distance well, and the heart rate monitor seems WAY more accurate than the dedicated exercise machines at my local gym.



*by reasonable, it does take a minute or two to sync to the satellites each time. That's the only thing I could possibly think of improving, but it's not a big deal. Being the super-impatient person I am, I often turn on the watch, set it on my front porch, go back in and change into my running outfit, and by the time I come back out it's ready to go.



I haven't seen the pacing issues others have reported. I'm a beginning runner... but if I keep a solid pace... it reports about 10mins/mile... if I push a little harder... about 9mins/mile... if I let up... about 11mins/mile. It seems very consistent over my entire 2-2.5 mile run.



I have a 2.1 mile run where I've done the same exact route about 6 times... and when I compare the maps of each run... they overlap almost exactly.



I have thyroid and heart issues, and this watch gives me the confidence to know I'm not exceeding my max hr for too long (I can easily get into the 180's) and gives me the feedback and stats to keep me motivated.



Last but not least, I've bought dozens and dozens of items from Amazon over the years, and this is the first review I've taken the time to write - hope that gives you an indication of how happy I am with this product. ;-)'


Detail Products
Detail Reviews
Click here for more information