I am continuing to get low sugars during 45 to 60 minute rowing workouts. I turn down my insulin right before I start and carbohydrate load with 40 to 45 grams of carbohydrates. I would like to go even longer than 60 minutes. What should I do?

If low blood sugars occur during a workout, a couple of tips may help decrease the occurrence and/or the severity. First, I would recommend a pre-exercise number (i.e., 150 mg/dl [8.3 mmol/L], for example) to shoot for before starting a workout. To increase the chances of hitting a pre-exercise number check your blood sugar twice before starting. Check once at an hour and a second at a half hour prior to the workout. This gives a better look at which way the blood sugar level is going rather than looking at one number. It also gives a half hour to make any adjustments (food or insulin).

Next, I would recommend decreasing the insulin about two hours prior to the workout and not right before. The insulin used in the vast majority of pumps is rapid acting (i.e., NovoLog, Humalog, or Apidra). This type of insulin will peak usually within one to two hours. Using a temporary basal rate just before the workout will not be effective until one to two hours into it. Remember, exercise can have an insulin-like effect,so having too much insulin on board can be a quick way to get a low blood sugar.

RP