yes, i use my garmin-equivalent (polar 625) in races.<br><br>
here's the main thing: i've been racing long enough (ummm, 28 years, yikes!) to know that races are magic. that's why we do them. so many times during my pre-race warmup i'm doing some slow pace and just don't feel that i'll be able to hit race pace in just a few minutes. then i get to the starting line, gun goes off, wham! magic!<br><br>
so while i do check my pace and heart rate during the race, i leave plenty of room in my head for the magic race factor. in a marathon, i use the pace up through mile 18-20 or so, and then i let the magic happen. but mostly i record my race data for later analysis, and it's helped me to learn a lot.<br><br>
what have i learned? during 2006 i tracked my average (well, median) race heart rate and found that it varied in a predictable way, as the logarithm of the race distance. there's plenty of scatter, i.e. since that time i've raced 5ks at 172bpm, but the fit predicted a marathon median heart rate of 154bpm. in phoenix this year i ran starting with 144 and going to 160bpm, and the avg. was 152bpm... close enough for government work.<br><img alt="" src="http://www.noao.edu/noao/staff/mpenn/personal/race_hr.jpg" style="border:0px solid;"><br><br>
what else have i learned? in three marathon bonks, i found that at exactly 2 hours, plus or minus 5 minutes, i bonked. my heart-rate started a slow decline as i slowed down and resorted to run-walk survival shuffle. i struggled with training, pacing, etc... but looking at the comparison and how uniform each bonk was, it freed me from thinking it was poor training or lack of mental toughness: the data convinced me there was some real physical thing going on in my body. after talking it over with some people i started using gels, and since then i've set two (bonk-free) marathon prs, and now i'm looking for the third.<br><br>
by looking at your race data, you can make predictions for future races. maybe more importantly you can look at bad races and learn something valuable. so use your garmin, but don't abuse it.<img alt="" class="inlineimg" src="http://www.kickrunners.com/forum/images/smilies/smile.gif" style="border:0px solid;" title="Smile">