Could not agree with this more: with a little insulin on board, a quick walk (even 5 minutes) has a profound impact.

Calf raises are absolutely diabolical as well, if you haven't tried them. There's some lore around this that the calf muscles are better adapted to absorb glucose, I haven't dug in other than to verify they do work.

The invention of the CGM might only be second to insulin in improving the lives os T1Ds.