Carbing up before intense exercise

Any tips for healthy carbs just before intense exercise? My daughter is training for black belt and we just found out about a 4 hour boot camp coming up. If we have to stop during the training for carbs she won’t pass because it’s a timed test. What works for you?


Does she use a pump MDI?

As a pump user, I setup a temp basal at 50% 2-hours prior to intense exercise and keep it rocking 1-2 hours post. With 15-20g of carbs I can keep my BG steady…if not on a slow rise. The challenge I typically encounter is post exercise rise due to the basal reduction and metabolic slowdown. So, I will usually take a bolus after the temp basal to level out any BG bump.

Hi Tiffany @Trussell001, to answer this, I would need to know what your daughter has experienced at other workout times involving “intense exercise”. Intense exercise differs from person to person and she should base what she eats [or doesn’t eat] based on her prior experiences. also, insulin adjustments - increase or decrease - should be based on how exercise affects her.
Keep in mind that aerobic exercise generally lowers BGL while anaerobic exercise generally increases BGL:. The operative word is “generally”. In the past when my body could tolerate extended intense or anaerobic activities I found my glucose increased because my muscles were demanding to be fed so my liver released large quantities of glucagon. Now when I prolong what I call my moderate exercise I cut my basal insulin very low and use a reduced [insulin] carb ratio at prior meals - on those days my real low is in the evening four hours after my exercise is complete.

I’m T1 and did 60 and 100 mile bike rides. I spent a little time with a knowledgeable owner of a triathlon supply store to find the right mix of nutrition. I relied on Bonk Breakers for good long-term energy. Side note: while my daughter isn’t diabetic, she had periods of low blood sugar during intense soccer training. We finally settled on lentil beans before practice. She hated but they worked. A good mix of carb and protein. Also consider glucose tabs for a quick fix.

Sometimes I carb up before exercising, but I have also suspended my pump until my BG is at an appropriate level. That means I am not receiving any basal for that period of time. Suspending instead of carbing means no eating, and less insulin. I also suspend my pump to help correct a low. You have to be careful to not suspend for too long.

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I suspend my pump and detach it for up to 2 hrs of exercise. How long is too long? If my bg pre exercise is at a level where in the past it could drop to a low I will have s piece of granola bar or a couple glucose tabs just prior to ex. I am 58 and a moderate exerciser-am your to hour and 1/2 of Pilates, yoga, or walking is my current workout. I’ve been t1 diabetic for a little over 2 years.

I always try to eat a bigger carb meal the morning or night before and use some Gatorade. I always try to start an intense workout between 225 and 275

I’m T1D and a competitive athlete and face this conundrum often. There are two elements to consider:

  1. Insulin Basal rate - if your daughter is on a pump, you should consider lowering the basal rate. If your daughter has a pump, this is easily accomplished. If she takes a longer lasting insulin, like a Lantus, then she can take less.

  2. Diet - additional carbohydrates and / or protein to cover for the exercise. She will have to take additional carbs or protein to help cover the additional exercise duration. Be mindful of the fact that if she lowers her basal rate, she may not have to increase the amount too much, else the blood sugars may spike too high.

Hopefully, you and your daughter have been keeping track of the effects of diet and exercise to know the effects of temporarily lowering a basal rate (or taking a smaller long lasting insulin dosage) and eating before and during exercise.

If your daughter is a competitive athlete, then perhaps she should be working with your endocrinologist to determine a useful “sports” basal rate.

That being said, does the dojo and sensei know that your daughter is diabetic? I find it hard to believe that if they did know this, they would prevent her from testing during the event.

Does she wear a CGM? As a competitive athlete, I find wearing a CGM incredibly helpful, especially during endurance (1-4 hours) events.

You are entitled to reasonable accommodations under the Americans With Disabilities Act. If she needs a break then she’s legally entitled to one.