My daughter is a freshman in college and competes on the women’s soccer team. The team is participating in spring conditioning, which consists of 6:00 a.m. weights for one hour and 45 to 60 minutes of sprints/800s. Her morning blood sugars range from 90 mg/dl [5.0 mmol/L] to 150 mg/dl [8.3 mmol/L]. She eats breakfast, boluses for her breakfast (she is on a pump) and finds that by the second hour of exercise, during her running, her blood sugars are at 300 mg/dl [16.7 mmol/L]. This means she has to sit, correct her blood sugar and miss practice. She is so frustrated right now. What can she do? Is it possible that the weight training is depleting her insulin and that she may need more? All the articles I have read talk about hypoglycemia and exercise. It also seems we have had to increase her basal rate a few times. Is this also due to the weightlifting?

Weightlifting and sprinting can cause blood sugars to spike during a session. This type of exercise is considered anaerobic or without oxygen. The greater the intensity of the lifting or sprinting, the more potential for a spike in one’s blood sugar. That said, it depends how much insulin is on board, too. There are a number of studies that show weightlifting can cause this spike, but there is the likelihood the blood sugar will drop hours afterwards similar to aerobic exercise or with oxygen.

If there is a pattern, there are a couple of things to consider. One is increasing basal rate on the pump an hour or two prior to lifting or change the insulin to carbohydrate ratio (i.e., one unit to cover 10 grams of carbohydrate to one unit to cover 8 grams as an example) within a couple of hours of lifting. Drinking more water may help to decrease high blood sugars a little, too, if dehydration is a factor.

RP