I am an avid racing-level cyclist. I currently use a pump and find that after 2 hours, no matter what, I always go low, unless I use zero basal. I finish races and rides with normal glycemia. I am wondering what evidence is there for or against this practice? What do you advise patients at this level of intensity to do, other than consume tons of calories (which I am sure you can appreciate is hard to do when riding)? Thanks for your time.
The first step to protect yourself from lows is to start your ride after a meal. This will ensure that you are starting your ride at a higher blood glucose level. Secondly, for your particular circumstance you may want to temporarily suspend the basal pump dose. At Joslin, in this type of situation when we recommend that the basal dose be suspended, we suggest doing this 1 hour prior to the start of the longer duration activity. You can keep the basal rate on the pump suspended for up to two hours, and we don’t usually recommend suspending it for longer than that. When turning the pump basal rate back on, make sure to turn it on at a lower dose than normal. This reduced basal rate is usually 40% less or more than your usual basal rate higher. As you experiment, you should seek advice from a diabetes pump specialist .