Would you recommend a CGMS?

I’ve been diabetic for the last 18 years. I recently started using an insulin pump. In high school I played soccer, basketball, and was a sprinter on the track team. I continued running on the track team in college. Now that I am done sprinting I have been changing my focus to longer events, usually 5ks but I want to run a very slow (I am not a distance runner) half marathon. Since I’ve been on the pump I have been able to get better control, but I am running low much more often. I haven’t been able to run for the last month as every time I get up to run before work my blood sugar is around 50. Obviously I need to continue to tweak my basal rates, but I was wondering does anybody use a CGMS and would they recommend one for running (and a sprint triathlon too someday)? Where do you keep it when you run so that you can see your numbers (or trends really, I know about the accuracy issues)?

YES! I run regularly, and during the cooler weather routinely do 10-14 mile runs. CGM and the pump have been a tremendous help. It’s imperfect, but you can adapt to those imperfections. For example, the CGM lags behind actual drops in bg, so you don’t wait until it says ‘60’ to treat a low. But you can do it pre-emptively by treating when you see sharp trends downward (or when you hit a higher threshold like 90 and are declining). I am now often (but not always) able to pre-empt lows before they slow me down. They can also help to avoid end-of-run highs by telling you when your bg is climbing, due to basal reductions or an increase in intensity. My routine is now pretty optimized, thanks in large part to CGM. It still needs tweaks now and then, but it’s a fantastic tool!

The downside is that CGM can be an adjustment. I use the MM. It took a few months to get adjusted to the technology and optimize my usage. But having both the pump and CGM in one unit is convenient. You may need to factor the learning curve into your training program, depending on how aggressive it is. I don’t personally do races, or triathalons, so I can’t add much in terms of the training and considerations for race day.

Good luck! It sounds like you’ve got a great goal.

You definitely have more time as a diabetic than me, but I can provide my view on CGM/pump. I train for triathlons, including the Ironman, and use the CGM all the time in training. I agree with you that you need to tweak your settings on the pump as you shouldn’t be waking up with lows like that. BTW, I use the Omnipod and Dexcom.

For training, I use both the pump and CGM for both. I put the CGM in a plastic bag (sandwich) to keep it dry and on the bike I put it in my back pocket to reference occasionally and on my runs I put it in my water belt. If the WO is over 2 hours I also carry a small test kit just in case the CGM stops working for some reason. I do want to fashion somehow a way to put it on the front of my tri bike to have more of a “dashboard” eventually. On my motorcycle I have a Ram mount that I use that is awesome. Depending on the workout length, intesity, heat of the day, etc I usually dial back my basal about an hour or two in advance ~30% to help my BGs and then will eat somewhere between 20-60grams per hour. I definitely recommend a CGM as it’s a huge benefit for workouts, especially as you start doing longer distances.

I also use the MiniMed Realtime CGM. It is awesome. When I swim, I take the pump off, which is also the CGM receiver. Then when I return, I go to the menu to ‘Find Lost Sensor’ and it takes a couple minutes to reconnect. I think the CGM Transmitter has a 5 minute interval between transmissions.

The best thing about the CGM is something I don’t need anymore, and that is overnight monitoring. It will wake (my wife who wakes) me up in the middle of the night if I go low. I can set my alert levels. I’ve fine tuned it to a high of 160 and a low of 70. It has been so much of a help that I rarely have overnight issues any more.

(FYI: I’ve been told that those in the business wish to distance the newer, immediate-reading CGM’s from the older, find-out-after-a-week CGMS systems.)

Well I met with a Dexcom rep today and she set me up on a trial period over the next 2 weeks or so. I am really excited to give this a try. Maybe I can get rid of the night time hypos and be able to run. And I will be able to see how I trend during my workouts. I am excited! Thanks guys!

So where do you guys keep the CGMS receiver when you work out? Do you use it to help monitor your activity while actually on a run or a bike or do you analyze it later to look for trends and to see if you are climbing and to figure out where your basal rates need to be tweaked?

I keep mine in a plastic bag in my back pocket (bike) or in my water belt (run). I’ll reference it occasionally, every 30 mins or so, to check trending. The only adjustments I generally need to do is eat more to address downward trending. The workout for me generally works my BG down. I adjust basal before the workout to be appropriate for the intensity, distance, temperature, etc.

Ditto what Todd said. Unless I’m suspicious that I’m going to encounter a problem (like I took a big bolus a few hours before the run) then I’ll only check every 20-30 min. Lowering my basal (starting about 15-30 min pre-run for about an hour total) keeps me pretty stable most of the time, but if it starts trending downward then I’ll use glucose gel (arrows) or goo (slow decline) depending on how quickly it’s dropping.

Downloading the data will definitely help you to figure out when and how much to adjust your basal, but having it to check during the run is hugely helpful.

I was a sprinter in college too. Had to slow down a bit after I shredded my achilles running masters meets. I mostly run on a tradmill, occasionally on the streets, but I always have my Dexcom with me. Some great advice in this thread but Tom hit the nail on the head wihen it comes to how I use it. It’s easy to just set it on the treadmill and check it every 5 minutes to look for the trend arrows. Depending on where my BG was at the start of the run, I know that as soon as I see the downward arrow, I have about 10 minutes left before I go hypo, so I’ll either take a fast acting carb or finish up within that time.

I just carry the receiver in my hand when I run. Makes it easier to monitor.

Good luck!