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Message: <blockquote data-quote="SimonP78" data-source="post: 2746442" data-attributes="member: 556474">I forgot to answer the original question too.There is a trade-off, higher intensity aerobic exercise will use carbs faster, but you can't maintain this level of exertion for as long as lower intensity aerobic exercise and also your body will tend to release more exercise-related stress hormones, which cause the liver to convert stored glycogen into glucose. If you can maintain high intensity aerobic exercise for long enough (an hour or more) your liver will run low on glycogen and/or your hormone response will abate and the hepatic glucose generation will taper away. You will then start running low even while doing high intensity exercise, which at the start may well have made you run high. Anaerobic exercise is a limiting case of the above, you really can't do this type of exercise for any significant duration of time and definitely get a hepatic glucose response.There is also an increase of insulin sensitivity with exercise, both acutely while you exercise and also after you have been exercising. I don't know whether there's research looking at how insulin sensitivity changes with exercise type/duration and how these effect the duration of post-exercise muscle insulin sensitivity, but I would guess it's a combination of duration and work done (i.e. power expended) as a proxy for glucose requirement, which is the underlying goal of the sensitivity changes. The post-exercise sensitivity may be a tapering of the former effect but certainly also has some relation to how much glucose needs to be reabsorbed to replenish muscle (and liver) glycogen stocks. Even very low intensity exercise ("fat burning") still burns carbs, though I don't know how this affects insulin sensitivity. It's probably quite hard to pick apart as when I ride at this intensity it's for a long time so I definitely used quite a lot of carbs as well as burning fat. There is probably some research somewhere. So to get an immediate reduction in blood glucose the ideal exercise is one which burns as much energy as possible without producing any stress response. Walking, mowing the lawn, gardening, etc., are more effective from that point of view than riding a bike is for me, though that may well be because I habitually ride too fast! If I sit inside on the turbo trainer at a reasonably low power for 30min I can get my BG to drop precipitously, but it's very hard to ride like that outside.Another interesting effect related to habituation is that I find if I've not been doing much riding (it's generally cold and wet outside right now and I've had a lurgie) my post-exercise response is massive (my dawn phenomenon will be gone for a couple of days and I'll run low overnight even after a reasonable 80km round-trip commute) whereas in the summer when I ride much more I'd barely even notice any change in BG after a ride like that. There is probably an optimal level of and interval between exercise for a diabetic such that the gaps are long enough to elicit a decent increase in insulin sensitivity without the body becoming habituated to it (which would also have the beneficial effect of avoiding overtraining/wearing yourself out!) Experiments to be done once the weather improves (though at that point it's quite hard to take multi-day long breaks between rides as it's nice out <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" />)</blockquote>

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