The caveat mainly targets those on some low-carb dietary regimen. If you were to break a fast (can't give a specific fast length, sorry) with exercise then maybe have a banana 15-30 minutes or so before starting, depending upon your metabolic speed.
Does this apply to you? If a highly confident no, then have at it at your own liability!
Do you have a citation for 15-30 minutes being a reasonable time for blood glucose levels changing in response to consuming a banana? I remember reading that it takes significantly longer than that, up to 150 minutes, but I can't find a proper source at the moment. The closest I can find is the 4-hour body, and I don't know how trustworthy it is. It also says that fructose may lower blood glucose levels.
This is the public group instrumental rationality diary for June 1-30; it's going up pretty late (sorry!) but entries for earlier in June are welcome.
Thanks to cata for starting the Group Rationality Diary posts, and to commenters for participating!
Next diary -- July 1-15
Immediate past diary -- May 16-31
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