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Low Blood Sugar After Workout - Please Help

J

Jimmy37

Active Member
I have started going to Gym to try and improve my fitness and control my diabetes better. I was advised by my Diabetic Nurse that the working out will help control my diabetes and also my blood pressure. I take Humalin M3 twice a day 40 units in the morning and 40 units at night. I checked my blood sugar level before going to the Gym and it was 12.9. after the gym I checked again and it was 3.8. I had two small oranges straight after my blood sugar level readings. When I went home I then had a bowl of Museli ( 18 grams of carbs) with milk and a slice of wholemeal bread (14 grams of carbs) I then waited 5 hours before I had took my Insulin. Because I was advised by my Diabetic Nurse to reduce my insulin after excerise I took 35 units. I then had Dinner which was Chicken Breast with wholegrain rice (because it was Uncle Ben one serving contained 31.2grams of carbs.. I then checked my blood sugar level at 9:30 which was 2 1/2 hours after meal and it was 1.9. I am shocked it went so low because of all the carbs I had after the Gym. I then had 2 slices of wholemeal bread, banana, 4 sweets (skittles). I then waited 1 hour and checked again it was up to 4.9. I then woke up about 2am and my blood sugar level was 1.8 I really do not understand why my blood sugar was dropping so quickly even after the carbs after the Gym.From my carb count after the Gym and dinner my meal I make it over 60 grams of carbs so I do not understand why my blood sugar was 1.9 at 9.30. If anyone can help to understand I would be great up.
 
You need to ask a health professional as these hypos are serious, especially if they are happening while you are asleep.
 
Eeek!

Sounds like you're having a pretty tough time with that @Jimmy37.

Exercise will have the immediate effect of increasing your insulin sensitivity. A basal of 40 units morning and evening is already pretty high and you could find needs adjusting (reducing) by more than 5 units on a day that you exercise. (Exercise regularly and you will need even less)
It's hard to offer much advice without understanding a bit more about your activity - so how long did you exercise for? How hard did you work out (what was the level of intensity) etc. All of this impacts on what you would ordinarily expect with your activity.
I was a bit confused by your comment 'I waited 5 hours before I took my insulin' - do you mean you waited 5 hrs before you bolused for the meal, or was that when you had your 'morning' basal? (Apologies for being a bit dense!)

To help you out a bit, for an hour of aerobic exercise you can pretty much expect to burn through 60g carbohydrate. In order not to suffer with low blood sugars later on in the day or that night, (and assuming your body is not adapted to running super low carb) then you're going to have to expect to at least replace that amount of energy.

When you exercise, your muscles and liver become depleted of glucose. They have to replace this by drawing glucose out of the blood stream. If you burnt more than 60g of carbs during your exercise, then there is every chance you will suffer a low blood glucose level at some point after your activity. The opportunity for this can be exacerbated by taking a large dose of insulin, as it enables the muscles to take up glucose much more readily (so you can see a rapid blood glucose fall).

Watch the TeamBG movie below which might help you get your head around the basics.
Have you considered getting a insulin pump?

Unfortunately there is no magic answer for you - it's just going to take a bit of trial and error, lots of testing and note taking. Before long you'll start to see a pattern and be able to work out a strategy that works though, so keep it up!

www.teambloodglucose.com

 
Exercise will increase insulin sensitivity quite rapidly. Especially if it is of high intensity.

80U basal is pretty high to be honest.

I'm 95kg 6ft 4 and my total daily dose is around 40 units. 20 unit basal the rest bolus.

Use glucose tablets to correct lows, quicker and make things easier also less calories.

You don't want to be going to the gym to lose weight and get fitter, then have to over eat due to hypos.

It will have to be trail and error, but I'm sure you'll get there in the end.
 
One of the things to discuss with your team is whether twice daily insulin is really the best treatment for you given your change in lifestyle. While it going to the gym will undoubtedly help improve insulin sensitivity and blood pressure, it can also play havoc with glucose levels if you have an inappropriate treatment regime.

Most of us who are very active use the Multiple Daily Injection model (known as MDI) or a pump. These give you a lot more flexibility with regard to the amount of insulin that you need to give to yourself and the timing of the insulin. Doing a lot of exercise on products like Humulin M3 can be difficult.
 
@Jimmy37, it sounds like your sensitivity to your insulin is improving with the gym work.

I suspect you need less insulin, and I don't just mean during exercise!

I'd suggest taking a step back, record BGs and carbs when you aren't exercising to simplify things (a 3am check is probably necessary I'm afraid). I'm unfamiliar with Humulin M3, but it sounds like you've discussed the strategy for reducing your insulin for exercise with the nurse.

When I first started to exercise I was already diagnosed with T1, needed to reduce insulin and take on carbs for exercise. 80g of them just to get through a 1 hour run! It's a case of you have to start somewhere.

The carb requirement does seem to come down as fitness improves, but that will take time.

Good luck.
 

I am going to the Gym 3-4 times per week and I do 45 mins cardio at the moment. I mainly use the Cross Trainer at I set it to level 16. The maxium level it goes up to is 24. I burn about 730 calories per session. I have now reduced my Humalin M3 dose to 30 units morning and evening as recommended by my Doctor. The Doctor advised that I take a break from the Gym for a while until I see my Diabetic Specialist Nurse. Hopefully my Dibetic Nurse will be able to set me on the right track
 

That's good @Jimmy37 - is the reduction helping your BG control?
Try to gather as much info as possible with regards to your training - your BG levels before, during and after, along with what you are eating. Keep plenty of notes - that way if will be far easier to see what adjustments or determine what strategy is likely to work best for you.
Exercise and diabetes can be a bit of a specialist area so you may find that your diabetic nurse is in unfamiliar territory. If he/she would like any guidance or support please do ask them to get in touch with www.teambloodglucose.com. TeamBG are supported and guided by Imperial College London and have access to the latest research in exercise with diabetes and will be happy to help.
 

Well since I have been on the 30 units morning and evening my blood sugar levels seems to be a bit higher. I am not going to the Gym because my GP wants me to take a break unitl a see a Diabetic Specialist. I check my BG before lucnh and it is between 3.7 - 4.5. I then check again before dinner and it is between 9.5 and 11.5. I then check before bed and sometimes it can be 9.5 or 13.5. Last night it was 15.5. In the morning my Blood Sugar levels have been 9.5 for the last two mornings since I have been on the reduce Insulin. I am keeping records of what I am eating and checking blood sugar levels. My lucn mainly consist of a wholemeal bagel and salmon 2 bagels, Dinner is Chicken and Pasta or Wholemeal Rice. I do tend to snack at work sometimes I will have a 4 Jacobs Crackers and 4 TUC biscuits. I am not sure what is going on now
 
Hi , That usually happens when taking insulin and working out you can have a drink (lucozade) Which actually helps in hypos that's going to help
**hope that helps**
 
Depends upon the workouts that you are doing... You should be testing directly before work out, during and directly after.
Your gym programme should be tailored to you personally, especially if it was under a referral scheme.
I was referred 8 weeks ago for a 12 week programme and it has been fantastic with a personal trainer for 2 1 hrs sessions each week. This ups to 3 1 hr sessions this week and as of 1/9 I will be by myself. I have had a full programme individualised to myself.

I do a mixture of good warm up, lower torso, upper torso and mat exercises.

I am not allowed to exercise if under 4.4 or over 13.0 but have kept levels betwen 5-7 consistently.

You need to consider very carefully your food and insulin regime and doses... If I am under 5.5 1/2 way thru my gym then I have a 15g gluco juice which keeps me level to the end.

However you feally need to look at your food pre gym.. Plain nuts 2 hrs before would be my choice.. However you need to lower your doses too.
 
Jimmy37 said:
I do not understand why my blood sugar was 1.9 at 9.30. If anyone can help to understand I would be great up.
Click to expand...

You sound like I was some years ago, with hypos at bedtime. Not saying you have what I have or anything but it's something to consider if you're still trying to figure it all out.
Try going 3 to 5 days without bread, rice, pasta or starchy veg (potatoes etc) and anything with added sugar in it and see whether it helps the hypos.
If it does then you know controlling carbs is the way forward.
 
This could actually kill him.

Or did you just misread it? he said his blood sugar during the night was 1.9 (one POINT nine), not 19. Your advice would be good if he had said 19.
 
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What is happening is that exercise reduced your need for insulin, so you cut your insulin. Thats perfectly logical and would probably have worked well. It probably would have raised your blood sugar enough to CONTINUE with your exercise routine. (A switch to MDI would make your control of this process better, but this was not a bad move at all.)

But then you ALSO cut your exercise (on the advice of your GP), and that obviated the need to cut your insulin in the first place. So that was NOT a good move.

Or you can reverse the argument: stop exercising but keep your insulin intake high as it was. But that is not what you want, is it? because that won't make you fitter and healthier.

You should talk to your diabetes team, and before you go, read up on MDI and how to manipulate it for exercise routines. Then you will be more prepared to discuss it. also there are lots of discussions about this on this forum.
 
RuthW said:
Or did you just misread it?
Click to expand...

Don't be nasty, I was only making a suggestion and I made that clear in my post.

I also said those were the same symptoms as I was having some years ago, so I speak with experience on the matter, and through trial and error and some informed decisions I found out what genuinely worked for me, and I'm not dead. In fact I've never felt more alive in my life.

Thanks for your feedback all the same.
 
Sorry, I wasn't trying to be nasty. Just very, very clear for the OP's sake. I genuinely thought you might have misread it, and given he is a fairly new diabetic, I thought someone should point out that your suggestion was dangerous as clearly as possible and as soon as possible in case he tried it.

You know, when people are on the app, rather than the website, they can't see your signature, so they can't tell whether you are T1 or T2. I guessed you are probably Type 2, but I also didn't want to derail the thread into a T1/T2 differences discussion.
 
I will agree with the other members for you to go and speak to your doctor on this issue. Hypo is really serious and should be investigated thoroughly.
However, Exercise has the same effect on blood sugar as insulin does, and you are already taking high level of medication, therefore it is possible the reason for the hypo.
Your doctor will be in a better position to administer the adjustment in medication.
 
Based on what you described your meals to be, your are still consuming too many carbohydrates.
Carbohydrates turns into glucose and that increase the level of sugar blood sugar.
Has mentioned before exercise as a positive effect on your blood glucose level similarly to insulin, so taking it out of your routine was not the best move.
what you need to do is visit a holistic dietitian/ diabetes specialist and work on your food consumption.
do some moving at least 20 minutes per day.
 
Hi everyone
I am type 2, have lost 4 stone in one year following low carb. Did go to the gym for 3 months earlier in the year and was feeling the benefits but unfortunately was experiencing low blood sugars. Looking to go back to the gym at weight loss has ceased due to little exercise. As I follow very low carb 25-30g a day, I need a good snack prior to working out, any suggestions please?
 
Hi Jimmy37. The scientific answer is to look at the insulin and diet regimens of T1s who have been doing this sort of thing successfully for decades, then modify that according to your own personal circumstances. Unfortunately you won't get much help with that from doctors. Same with LCHF. You need to learn it yourself.
t1diabetesafter55.blogspot.com.au
 
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