I have a 5th grader who had a pre meal BG of 454, ate his lunch of 73 carb gms (after getting 5 units of Novalog insulin per parents instruction). He was to run a timed mile run in gym class immediately after lunch. I instructed not to run. I did not check for ketones because the blood sugar was so high, that it seemed to preclude any exercise. But I have not found much documentation of blood sugar levels and holding exercise, just the presence of ketones? Any input into this situation?
This article states that if your glucose is over 250 to check for ketones and not to exercise if it is over 300 or if ketones are present. The presence of ketones can put you at risk for ketoacidosis, a potentially fatal drop in ph of the blood.