From my perspective walking my bg levels down from 238 to under 140 every day after liver dawn effect; once one exercises hard enough and gets the temp glucose sites in skeletal muscles pulled down sufficiently, then the blood stream will see its glucose come down as muscles start pulling in glucose from blood stream.
Initally one will see little activity as temporary stores of skeletal muscles provide the energy. For me; it took 8 - 1/4 mile loops to walk crap off.
The first 6 loops - not much happened but as one did loop 7 and 8 - then I would see BG drop fast.
Any jump in bg will be due to the following:
- any foods left over in intestines dawdling along and then under exercise get boot/glucose release acceleration.
- bg drops low enough to cause liver to kick in from its storage booting BG up. Normally it should not boot higher than 20 % of nominal but for T2 - all bets off and jump can be all over. For me; I would see BG jump to 511/max and slide down to 278/311 as heart dilutes by pumping crap around the body.
without serious quick monitoring - cgms one can miss the key action.