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Biking and low blood sugar
njgiesler
Posts: 1 Member
Are there any bikers out there who can chime in on this? I'm T2 diabetic and have only been keto for about 3 weeks, only meds Metformin er 500mg twice a day. My blood sugars have been excellent, mostly in the 70s to 80s fasting and staying below 100 post meal. Blood sugar stays above 70 when I walk or jog, but about an hour after a bike ride I plummet into the 50s and have to eat a pretty big hit of carbs (10 -20 gr) to bring it back up again. I'm trying to stay below 20 gr a day so I feel like I'm blowing it when I do that but don't want to give up biking and don't want to die of hypoglycemia so feeling stuck. Any advice/insights would be welcome. Thanks!
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Note: I don't have the same condition as you, so take the following with a grain of salt.
How hard are you riding? If you stay in aerobic zone, of MAF training zone (Phil Maffetone), I would expect your blood sugar to stay closer to normal because you'll be in fat burning vs glycogen burning.
My logic is based on the assumption that your blood sugar is being used to replenish muscle glycogen due to hard riding efforts. If that's the case, and you wish to continue higher level efforts, you should be able to refuel those with higher carb intake without sacrificing keto/LCHF efforts. Ben Greenfield has discussed this on his podcasts, and I highly recommend them.
I am going to keep my training in aerobic, build a solid base at MAF for 8-16 weeks then perform shorter high intensity workouts for a few weeks to build speed.0 -
Are you feeling low blood sugar symptoms at that level? It's possible your ketones are high at the same time which would make sense. If you're not symptomatic it may not be an issue. Though certainly something to watch.
You might consider carrying glucose tablets or smarties candies with you and dosing 5-10 grams
Any carbs that are as close to pure glucose as possible to correct a low, I wouldn't even consider an issue. Just remember that you really only need to bring blood sugar back up to around 80 though.
If you're not feeling symptomatic, you may have high ketones fueling you. It still is probably not a problem to have some glucose even if you're not feeling the low. My daughter (T1D) tries to correct slight lows with things like nuts. But at 50, she would be having some candy or glucose for sure. She feels symptomatic around 85 though, which isn't even low0 -
Why are you staying below 20g/day? As active as you are I would think you could stay in ketosis even at 50ish???2
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It may also take up to 12 weeks for your body to stop thinking it still needs glucose constantly before it learns that it can depend on ketones.
Also, make sure you're replacing enough sodium, as electrolyte imbalances can play out in glucose management, too.2
This discussion has been closed.