And you did what ?
a) had your usual breakfast with a reduced dose of short-acting insulin and waited for your BSL to be > 6 mmol/l before setting off, or
b) had some Glucotabs and waited until your BSL reached > 6 mmol/l and relying on your long-acting insulin which you had reduced 20% last night you set off, or
c) corrected your BSL with breakfast or glucotabs and postponed your run til the afternoon.