(I'm from the UK so I'll be using mmol/L as units and taking <4.0 as hypoglycaemia.)
I remember being told that I should consume a small amount of sugar or reduce insulin dose sightly to increase blood sugar before any considerable physical activity. Only over the last year or 2 have I had to use this strategy regularly since starting at a gym. I remember being told that it was recommended to be >8.0 before exercise but in my own experience >10.0 is required to avoid hypoglycaemia after exercise. I'm simply asking why this is necessary. If my body does not produce insulin, how does the introduction of physical activity cause my blood sugar to drop? Are my cells absorbing the glucose without insulin? If not where is the glucose going?