November 8, 2003
Exercise and Sports
Question from Purlear, North Carolina, USA:
Why shouldn't my son exercise if his blood sugar is above 240 mg/dl [13.3 mmol/L], and he has ketones?
Current American Diabetes Association guidelines advise avoiding physical activity if fasting glucose levels are above 250 mg/dl [13.9 mmol/L] and ketosis is present. These guidelines also advise persons with diabetes to use caution if glucose levels are above 300 mg/dl [16.7 mmol/L] and no ketosis is present. Your own healthcare team may have more specific recommendations for your situation.
The reasons for these guidelines are as follows: In the state of ketosis, with elevated blood sugars and low circulating insulin levels, exercise may actually raise blood sugar levels due to the release of liver glycogen. This liver glycogen dump is a result of the body’s perception that there is not enough glucose available for energy. Recall that without the necessary insulin, blood sugar despite its elevation, cannot enter the cells. In addition, without insulin to allow glucose to enter cells for energy production, the body increases its reliance on fat calories. This produces additional ketone bodies, thereby worsening the ketotic state.
The use of today’s intensive insulin regimens allow persons with diabetes the flexibility to make appropriate dosage adjustments as needed to avoid or treat situations such as described above. Talk to your healthcare team about how these recommendations apply to your situation, and work with them to develop a treatment plan for blood sugar management which allows participation in the activities that your child enjoys.