Turn off insulin pump during exercise

In diabetic children and adolescents who use insulin pumps to control their blood sugar, exercising with the pump on has no benefit, a study shows, and may increase the risk of low blood sugar (Hypoglycemia) long after they stop exercising.

"We recommend that the pump be removed or turned off during unplanned prolonged exercise for the convenience of young diabetic patients," write Dr. Gil Admon from the Schneider Children's Medical Center of Israel in Petach Tikva and colleagues in the journal Pediatrics.

This is in addition, they emphasize, to the general recommendations that these children eat complex carbohydrates before exercise, monitor their blood sugar after exercise, reducing the insulin dose if needed, and increase the bedtime snack to prevent hypoglycemic events overnight.

Insulin pumps are gaining in popularity for insulin delivery among type 1 diabetic patients but there is no consensus regarding guidelines for proper pump use during exercise, Admon and colleagues point out in their report.

They determined responses to controlled exercise with the insulin pump on and the pump off in 10 type 1 diabetic patients 10 to 19 years of age.

Hypoglycemia occurs when your body's blood sugar, or glucose, is abnormally low. The term insulin shock is used to describe severe hypoglycemia that results in unconsciousness.

Causes, incidence, and risk factors

Hypoglycemia results when your body's glucose is used up too rapidly, when glucose is released into the bloodstream more slowly than is needed by your body, or when excessive insulin is released into the bloodstream. Insulin is a hormone that reduces blood glucose. It is produced by the pancreas in response to increased glucose levels in the blood.

The subjects exercised for 40 to 45 minutes on a bicycle roughly 2 hours after a standard breakfast and an insulin (Lispro) bolus. They consumed 20 grams of carbohydrates before and after exercising. Each subject exercised once with the pump on and once with the pump off.

"Children engage frequently in unplanned physical activity (and) our study was designed to mimic unplanned exercise," the authors note.

In a nutshell, they found that this type of exercise "is equally performed, perceived, and safe (in terms of acute hypoglycemia)" with the pump on or with the pump off.

The team did find, however, that late (after exercise) hypoglycemia was more common than acute (during exercise) Hypoglycemia and there was a trend toward increased risk of late hypoglycemia with the pump on during exercise.