I ride a bike regularly (year-round) for exercise, transportation, and recreation. I got a G4 a couple weeks ago. On Sunday, I did a somewhat longer and 'harder' bike ride than I'd done in a while and noticed a couple things. First, the monitor was almost constantly, and falsely telling me I was LOW -- as low as 30's - despite the fact that my meter had me consistently between 76 and 85 (after the first 30 minutes). Second, during the ride I hit a bump and my handlebar hit my stomach - I think it missed the sensor, but came close. Finally, the day after the ride, the readings were more on the low side of reality than usual - and I got the ??? a few times - especially when I took a short bike ride. That SEEMS to have more or less resolved itself, but is a concern.
Any suggestions as to placement of the sensor for bike riding? Anyone have experience with a lot of riding wearing a G4 sensor? Any advice at all? :)
I bike quite a bit for all purposes too, about 6,000 miles last year. I was previously on the 7+ until February when I got on the new G4. In my 3 years with Dexcom, I've just always put it on my stomach and it has worked well so I never tried elsewhere. The false lows can sometimes happen, and I think that's because this is reading the interstitial fluid and not blood, and I think once it goes low it tends to continue to read low until it more suddenly spikes (Even though in reality you might have been slowly climbing, assuming you ate or drank something to get away from the low).
I rode a hard 80 miles on Saturday and it was working great though. I have my weekly race tonight, and I've made a special holder for the Dexcom on that stem so that I can check it very easily while riding.
I have found although not a bike rider but many cardio workouts, that after a very sweaty workout I will get the ??? and also occasionally after a shower. I attribute that to water getting in where it should, the longest it lasts is about 3 hours...I think the time that it may take to dry out. But this is theory on my part.
I also experience lows after working out but it pretty much coincides with my meter, so no complaints there from me.
Good luck, I hope you will find the G4 as helpful as I have.
I prefer, as a bike rider, both MTB and Road riding to have my G4 on my upper thigh. I do not seem to have many womky numbers when riding, with it on the top of my legs.
