Effects of moderate-severe exercise on blood glucose in Type 1 diabetic adolescents treated with insulin pump or glargine insulin

J Endocrinol Invest. 2009 Jun;32(6):519-24. doi: 10.1007/BF03346499.


Background: Few papers focus on exercise-related blood glucose (BG) in patients on continuous sc insulin infusion (CSII) or multiple daily injections (MDI) with glargine.

Aim: The main objective was to evaluate the degree of glycemic control in Type 1 diabetes mellitus adolescents on CSII doing physical activity with pump switched on or off. These findings were also compared with a small group of patients on MDI with glargine.

Subjects and methods: Eight patients on CSII (basal rate continued or turned off in alternating sessions) and 5 on MDI joined 4 sessions of moderate-severe exercise.

Results: Post-exercise BG significantly increased with the pump off and was unchanged/decreased with the pump on and MDI groups vs baseline. The hypoglycemia rate was not different among the 3 groups at any time. Pump on: hypoglycemias more frequent both at bedtime (p=0.031) and at awakening (p<0.001) than before dinner and at awakening than at bed-time (p=0.044). Pump off: hypoglycemias more frequent both at bed-time (p=0.010) and at awakening (p=0.031) than before dinner. MDI: no differences.

Conclusions: Glargine is safe and reducing the pre-lunch insulin is unnecessary. Subjects on insulin pump should not stop the basal rate. If they stop the pump, some actions are advisable: pre-exercise insulin bolus, pre-sleeping snack rich in carbohydrates, slight reduction of the overnight basal rate. On the other hand, if the basal rate is unmodified, the ingestion of sugary drinks during the exercise, the reduction of the overnight basal rate, a reduction of the pre-dinner insulin bolus and/or a pre-sleeping snack should be considered.

MeSH terms

  • Adolescent
  • Blood Glucose / metabolism*
  • Child
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Female
  • Glycemic Index
  • Humans
  • Insulin / administration & dosage
  • Insulin / analogs & derivatives*
  • Insulin Glargine
  • Insulin Infusion Systems*
  • Insulin Lispro
  • Insulin, Long-Acting
  • Male
  • Physical Fitness / physiology*
  • Statistics, Nonparametric


  • Blood Glucose
  • Insulin
  • Insulin Lispro
  • Insulin, Long-Acting
  • Insulin Glargine