I just bought my first GPS watch last week, a Garmin FR910XT (with upgraded firmware to v2.60!), to bring my running to a new level. However, I discovered that the instant pace on this watch seems to jump all around the place (+/- 15 seconds/km) and that the pace displayed when using “Workouts” feature is so averaged that the pace seems frozen (it take maybe 30 seconds of walk before seeing number changing… slowly)! For its defense, it was a cloudy morning.
Since I would like to train using precise pace (my lactate thresold pace have a 10 seconds span), this wacth seems not suitable for my needs (at least how I currently use it).
I would like to have the opinion/suggestion of GPS watch’s advanced user about this. Is it all GPS watch that have this kind of accuracy? Is there a better way to use them i.e. used instead a foot pod, average pace on 500m auto lap, etc?
If you go to the GPS setting and look at the satellites, you’ll see the accuracy is usually around 15-19 feet. I don’t see how instantaneous speed can be calculated with that type of accuracy… I also don’t understand why you need instant pace. If you use your footpod, you might get better instant pace but thats still just an estimate based on your calibration.
There are numerous threads about the instant pace accuracy of the FR910!
Personally, i was aware of those when i bought my watch but still really like it. The thing is i mostly use lap pace (every 1km) in order to determine my pace as small fluctuations are normal in your stride anyway.
I think it is a great training tool as long as you are aware of these glitches and can work around them.
I just look at my overall lap pace which is averaged over 7 or so minutes by the end… It stays pretty solid and I can push it up to increase or slow it down to decrease… Not sure why instant pace is that important…
For the same reason, I use 10s average power on my bike as instant power jumps around too much.
I have been using various Garmin GPS HMs for six years. I don’t use the instant pace information. Today with a 910XT I ran 5 miles on a flat course closed to traffic and the watch is set up to buzz and vibrate every mile and tell me what my last mile pace was. Today I was shooting for 8 minute miles and each mile came up with in 5 seconds of that pace. I feel the Garmin GPS watches are very accurate, but not for instant pace information. Tim
Sorry If i might have misunderstood what you first meant!
As i suggested earlier, use last lap pace as it is a very good tool for training! You have feedback that is not instantaneous but yet gives you a good indication.
Plus it forces you to know yourself pace-wise! I can now guess to about 5s/k my running speed! (except for beginning of races, that’s another story)
If you are looking for a gps watch i still encourage you to get the 910 as just the swimming features are fantastic (IMHO)
My question is more about if it is the case for every watch or onlye the 910XT?
I love the features of the 910, but my old 305 was almost always dead on for instant pace, especially when away from trees and buildings. 910, not so much.
Instant pace has often been a complaint with Garmin products. My Polar RC3 seems to be much, much better at telling me instant pace. But, as others have said, you can use average pace to your advantage, and it seems that Garmins calculate that very well.
Use = lose? If so that is true, but it does not bother me. My main run screen shows time, distance, last lap pace (set to 1/4 mile) and average pace. I feel the 1/4 mile laps gives me decently accurate info to pace off of and the average pace lets me know if I am ahead of or behind my overall goal. I don’t miss having good instant pace because I don’t think I need to look at my watch more often than every 1/4 mile. Could get distracting.
Autolap .25 mile, last lap pace and avg pace. Guess more accurate if you glance at the watch a lot.
Autolap 1 mile, avg pace and instant pace. Better for longer runs or if you already have an idea of pace and only need to check every now and then.
Didn’t find much difference between those two. Currently using the second method. I use a footpod fwiw.
no gps works good enough to do that, unless you happen to be in an area with exceptional reception. some places dont get good gps signal I have a ride thats 55Miles that I do and my garmin 910xt always says its like 49.5 and other places its dead accurate. its like a phone signal works better some places than others
My 310 has been pretty good on instant pace. My experience is that it is either spot on (as confirmed during track workouts) or completely wrong (sometimes it tells me I’m running 8+miles when I’m obviously running closer to 6). I don’t really see it bouncing back and forth across a 30 sec range. 10 sec/mi tolerance is probably fair, but there are a number of things that can affect the accuracy. Buildings and trees present very real impediments to GPS accuracy. Clouds don’t help, but unless it is about to rain solid objects clouds won’t completely ruin your GPS signal.
Side note, your LT range is a range for a reason. Only on a treadmill will you run an exactly constant speed for an extended period of time. The real world has hills and corners and pace variation. It is ok for your pace to vary a bit. Being slightly inexact about pace hasn’t stopped anyone from being a successful runner. As far as I know, even the Brownlees don’t do 100% of their workouts on the track or treadmill.
The 910 has some issues with instant pace, and it is good enough for you.
The way to learn your “precise pace” is to learn how it feels. Not instantaneously, over time. Over long periods of time. Like full mile intervals.
Go on runs alone. Set the watch to a lap value of 1.01 miles. This will correspond better to 1.00 real world miles than setting the watch itself to 1.00. After a warmup, run a mile at a desired pace. Whatever you do, keep it even. Do not adjust. Then, when you go by the first split and see the time, make a ***minute ***adjustment. Nothing major. Something small. See the next split. Get used to holding a very even effort over the course of a whole mile. You will find yourself becoming very good at this.
If you run with the instantaneous pace or with short interval splits, you will find yourself making adjustments too often. Often enough that it is harder to get a feel for the pace you want before you are reacting and switching away…