GPS Watches

I use a Forerunner 205, which I wear on the top of my head, inside a small ziplock baggie, under a cap. Works great; quick to lock on; super-accurate. The 205 is, I believe, exactly the same as the 305 (same dimensions & weight) except the 305 includes a HR monitor for ~$20 extra - which obviously I don't use since I don't wear it on my wrist. For an extra ~$230 you get the waterproof 310xt (the 205/305 are "water resistant"), which doesn't seem worth it unless you're using it in a tri context. Katie, I do think there's value in accurate trace lines (no zig zags). It's useful information if you're not swimming straight - whether from poor sighting, currents, or what-have-you. No "swim correction" software necessary if you wear it under the cap, though. The watch loses the GPS signal only if it goes under water.

Thanks! I broke down and ordered it.

I have the Garmin 205 now, but I'm not having very good luck with it so far. Here's what I've tried: I took it with me in the car. It worked exactly as I would have expected. When I exported the data into Google Earth, I could see my path from home to Trader Joe's and back. (Pretty exciting, I know) I put it in a ziploc bag under my cap for a race. It only captured the start point. (I have it set to Auto Lap on the Start Point and any time I hit Lap. In this case, I never hit Lap.) I heard it beep several times near the end, I imagine because it was loosing its signal. I've tried it under my cap in the pool three times. The results were pretty much the same each time. I hit Start when I started swimming, Lap at the opposite wall, and swam 12 slow (mostly drill) lengths, no flip turns. I heard it beep several times, always near the far wall. Garmin Training Center: It shows 6 laps (I would have expected 12), but the distribution is bizarre. Screenshot is attached. Google Earth: I only see Laps 1,2 and 6. The only path it saved is between Laps 1 and 2. Image is attached. I'd love to get this working for my race on Saturday--any advice is appreciated.

KatieK - Your results are odd. I use my Garmin 205 to swim open water. I place it in my ISHOF Swimsafer dry bag which gets dragged along behind me. The dry bag is thicker than a swim cap. I suppose I make sure the watch face is facing upward, but that's it.

Hmm. I've never had any of the issues you describe - but I've never used the lap function, and I've never used it in a pool. It's awkward to fumble with it while it's under my cap, so I just press the start/stop button once when I start and once when I stop. If I need to calculate lap times I just go into the 'Player' function in Garmin Connect (the online service, not the Training Center software) and re-create them manually. See attached screenshot of a recent swim I did in Santa Barbara. As geog said, make sure the unit is facing up, and try to position it near the top of your head.

I carry a sextant and a book of trigonometric tables down the back of my suit :)

I use a Garmin for running but not open water swimming. I'm curious, with it being in your hat, does it ever fail, go into the wrong mode etc or does locking the bezel sort most of that out?

Thanks everyone for your comments. antenna faces up/forward, then the latex cap over everything, listening for the beep of an inadvertent button press (never happens). i don't press the start button until i'm in the water and ready to swim. Thanks for this and for the picture. Great idea using your goggles to anchor it. I did have it facing the opposite way. Katiek: are you using GPS to keep track of your laps in a swimming pool? No. I've been taking it to the pool to see if I can get the kinks worked out before my next open water event. I did another test today, positioning it with the antenna pointing up. I didn't hit lap, just Start and Stop. I started and stopped several times and tried positioning a few different ways on my head. My results weren't any better. On Garmin Connect, it looks like I am swimming across 12 lanes, and thru the parking lot. It looks better in Google Earth, but it still has me 18 meters outside the pool and swimming in random directions. I hear it beeping quite a bit which I assume means that it's losing its signal. There is no part of my head that stays completely out of the water, so I'm not surprised it's losing its signal from time to time. But I still wouldn't expect the results to be SO erratic. I have a race tomorrow, so I'll try it again and let you know how it goes. For the race, I'm turning the beeps off, setting it to collect data every second instead of using "smart" recording. I'm also turning off "Auto Lap" and "Auto Pause" (unless you guys advise me differently). I'm usually good at this kind of thing...

Katiek: are you using GPS to keep track of your laps in a swimming pool? I don't think is going to to work well in that scenario for a few reasons: 1) Flip turn will make the GPS loose track of the satellites 2) GPS coordinates are not precise enough for a good track in the pool 3) GPS measures your position at intervals and the sudden change of direction will affect the track. To keep track of your pool workout is better to use something like the Finis Swimsense. For OWS a GPS in a cap works great, look at my track in the La Jolla Rough Water: connect.garmin.com/.../113749552

One quick comment: My understanding is that USAF limits civilian GPSs to a maximum accuracy of 10m, is not unusual to see the GPS coordinates jumping 10-20 meters. You will get better results in a longer race. Read dcrainmaker's review of the 310xt to get an idea of they type of track you should get when using it for OWS www.dcrainmaker.com/.../new-garmin-forerunner-310xt-openwater.html (I know is not the same FR you have, but should be very similar) Good luck with your race tomorrow.