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Advice on managing exercise and blood sugar

D

DiabeticDi

Well-Known Member
Messages
259
Type of diabetes
Type 1
I am starting at the gym soon and as a novice I am worried about what my readings will do. Starting off with an hour on treadmill and bike, going mid morning. Do I reduce my Lantus at breakfast? How much do I decrease Novorapid> If I am too high or too low just before I go do I adjust?
 
I know it is not much help but "we are all different" and the same is true for exercise.

Typically, longer cardio exercise will result in falling BG and shorter exercise or resistance training will result in raising BG during exercise. Both may result in falling BG for 24 to 48 hours after exercise.
But, this will depend on how fit you are and how used to these types of exercise you are.
For example, someone who runs marathons every week may have little impact on their BG. Someone who has done no running before may struggle and this stress may cause their BG to rise rather than fall.

A couple of diabetes related things happen to cause this
- our bodies become more efficient in using insulin
- our livers release glycogen to give us energy to exercise and fight any stress our bodies feel

A few rules of thumb I adopt when exercising, especially when doing cardio like treadmill and bike.
- try to start exercise with a BG between 6 and 8
- if lower than this, eat something (about 10g carbs) without any insulin
- if higher, wait
- try to exercise 3 hours or more after your last bolus injection .. to reduce fast acting insulin "on board" as this makes my BG fall
- do not change my slow acting insulin before exercise.
- keep BG tester and hypo treatment with me at all times
- test after 30 minutes (or when I feel I am struggling more than I think I should), as soon as you complete your exercise and a few hours later (a CGM or Libre may help but remember they are 15 - 20 minutes behind your true BG and exercise may cause rapid changes to your BG which these may catch "too late")
- don't over do it at first - build up the exercise

I was repeatedly told it takes a few days for changes to long acting insulin to take affect so there is no point changing it unless you are exercising every day.
However (and this comes with a big warning), I found it helped to reduce my basal by 20% for 24 hours after exercise.

I exercise a lot.
Three years ago I changed from injections to a pump and found this helps my BG during and after exercise.

My exercise varies - walking (has no impact on BG), running indoors on a treadmill (my BG falls), running outdoors (my BG may rise, especially if the weather is rubbish or I am running up hill), spin classes (my BG falls), climbing (my BG rises), weight training (my BG rises) and, occasionally something completely different for a change (I tried flying trapeze last year).
 
Last edited by a moderator:
Start slow and gradual and build up over time and adjust insulin when required.
 
helensaramay said:
try not to start exercise with a BG between 6 and 8
Click to expand...

Do you mean the "not" there? (Awesome post otherwise.)

I would stress keeping the BG tester and glucose close. When you're working out hard at the gym it can be very hard to tell the difference between
- I want to die because I'm so exhausted
- I want to die because my blood sugar is going low
- I want to die because stress is pushing my blood sugar up.

If in doubt, stop and do a quick test. (And it has the bonus of letting you catch you breath for 30 seconds.)

Good luck, and enjoy those well earned endorphins rushing through your body after you've finished.
 
helensaramay said:
Oops, I will correct that in my post.
Thanks for the spot.
Click to expand...

No worries, (and I've just upgraded your rating to "winner" :)). Truly helpful post, and one that resonates very well with my recent cardio sessions where I discovered my blood sugar plummeting by 2 after each set of 10 45 second activities. (I ended up doing a blood test between each set!).
 
helensaramay said:
I know it is not much help but "we are all different" and the same is true for exercise.

Typically, longer cardio exercise will result in falling BG and shorter exercise or resistance training will result in raising BG during exercise. Both may result in falling BG for 24 to 48 hours after exercise.
But, this will depend on how fit you are and how used to these types of exercise you are.
For example, someone who runs marathons every week may have little impact on their BG. Someone who has done no running before may struggle and this stress may cause their BG to rise rather than fall.

A couple of diabetes related things happen to cause this
- our bodies become more efficient in using insulin
- our livers release glycogen to give us energy to exercise and fight any stress our bodies feel

A few rules of thumb I adopt when exercising, especially when doing cardio like treadmill and bike.
- try to start exercise with a BG between 6 and 8
- if lower than this, eat something (about 10g carbs) without any insulin
- if higher, wait
- try to exercise 3 hours or more after your last bolus injection .. to reduce fast acting insulin "on board" as this makes my BG fall
- do not change my slow acting insulin before exercise.
- keep BG tester and hypo treatment with me at all times
- test after 30 minutes (or when I feel I am struggling more than I think I should), as soon as you complete your exercise and a few hours later (a CGM or Libre may help but remember they are 15 - 20 minutes behind your true BG and exercise may cause rapid changes to your BG which these may catch "too late")
- don't over do it at first - build up the exercise

I was repeatedly told it takes a few days for changes to long acting insulin to take affect so there is no point changing it unless you are exercising every day.
However (and this comes with a big warning), I found it helped to reduce my basal by 20% for 24 hours after exercise.

I exercise a lot.
Three years ago I changed from injections to a pump and found this helps my BG during and after exercise.

My exercise varies - walking (has no impact on BG), running indoors on a treadmill (my BG falls), running outdoors (my BG may rise, especially if the weather is rubbish or I am running up hill), spin classes (my BG falls), climbing (my BG rises), weight training (my BG rises) and, occasionally something completely different for a change (I tried flying trapeze last year).
Click to expand...
Thank you very much, that is so helpful!
 
EllieM said:
Do you mean the "not" there? (Awesome post otherwise.)

I would stress keeping the BG tester and glucose close. When you're working out hard at the gym it can be very hard to tell the difference between
- I want to die because I'm so exhausted
- I want to die because my blood sugar is going low
- I want to die because stress is pushing my blood sugar up.

If in doubt, stop and do a quick test. (And it has the bonus of letting you catch you breath for 30 seconds.)

Good luck, and enjoy those well earned endorphins rushing through your body after you've finished.
Click to expand...
 
helensaramay said:
I know it is not much help but "we are all different" and the same is true for exercise.

Typically, longer cardio exercise will result in falling BG and shorter exercise or resistance training will result in raising BG during exercise. Both may result in falling BG for 24 to 48 hours after exercise.
But, this will depend on how fit you are and how used to these types of exercise you are.
For example, someone who runs marathons every week may have little impact on their BG. Someone who has done no running before may struggle and this stress may cause their BG to rise rather than fall.

A couple of diabetes related things happen to cause this
- our bodies become more efficient in using insulin
- our livers release glycogen to give us energy to exercise and fight any stress our bodies feel

A few rules of thumb I adopt when exercising, especially when doing cardio like treadmill and bike.
- try to start exercise with a BG between 6 and 8
- if lower than this, eat something (about 10g carbs) without any insulin
- if higher, wait
- try to exercise 3 hours or more after your last bolus injection .. to reduce fast acting insulin "on board" as this makes my BG fall
- do not change my slow acting insulin before exercise.
- keep BG tester and hypo treatment with me at all times
- test after 30 minutes (or when I feel I am struggling more than I think I should), as soon as you complete your exercise and a few hours later (a CGM or Libre may help but remember they are 15 - 20 minutes behind your true BG and exercise may cause rapid changes to your BG which these may catch "too late")
- don't over do it at first - build up the exercise

I was repeatedly told it takes a few days for changes to long acting insulin to take affect so there is no point changing it unless you are exercising every day.
However (and this comes with a big warning), I found it helped to reduce my basal by 20% for 24 hours after exercise.

I exercise a lot.
Three years ago I changed from injections to a pump and found this helps my BG during and after exercise.

My exercise varies - walking (has no impact on BG), running indoors on a treadmill (my BG falls), running outdoors (my BG may rise, especially if the weather is rubbish or I am running up hill), spin classes (my BG falls), climbing (my BG rises), weight training (my BG rises) and, occasionally something completely different for a change (I tried flying trapeze last year).
Click to expand...
 
Brilliant, just what I wanted, so helpful. One question...if while I am at the guym I test and I am too low, what is the best thing to take? Glucose tablets? Lucozade?
 
helensaramay said:
I know it is not much help but "we are all different" and the same is true for exercise.

Typically, longer cardio exercise will result in falling BG and shorter exercise or resistance training will result in raising BG during exercise. Both may result in falling BG for 24 to 48 hours after exercise.
But, this will depend on how fit you are and how used to these types of exercise you are.
For example, someone who runs marathons every week may have little impact on their BG. Someone who has done no running before may struggle and this stress may cause their BG to rise rather than fall.

A couple of diabetes related things happen to cause this
- our bodies become more efficient in using insulin
- our livers release glycogen to give us energy to exercise and fight any stress our bodies feel

A few rules of thumb I adopt when exercising, especially when doing cardio like treadmill and bike.
- try to start exercise with a BG between 6 and 8
- if lower than this, eat something (about 10g carbs) without any insulin
- if higher, wait
- try to exercise 3 hours or more after your last bolus injection .. to reduce fast acting insulin "on board" as this makes my BG fall
- do not change my slow acting insulin before exercise.
- keep BG tester and hypo treatment with me at all times
- test after 30 minutes (or when I feel I am struggling more than I think I should), as soon as you complete your exercise and a few hours later (a CGM or Libre may help but remember they are 15 - 20 minutes behind your true BG and exercise may cause rapid changes to your BG which these may catch "too late")
- don't over do it at first - build up the exercise

I was repeatedly told it takes a few days for changes to long acting insulin to take affect so there is no point changing it unless you are exercising every day.
However (and this comes with a big warning), I found it helped to reduce my basal by 20% for 24 hours after exercise.

I exercise a lot.
Three years ago I changed from injections to a pump and found this helps my BG during and after exercise.

My exercise varies - walking (has no impact on BG), running indoors on a treadmill (my BG falls), running outdoors (my BG may rise, especially if the weather is rubbish or I am running up hill), spin classes (my BG falls), climbing (my BG rises), weight training (my BG rises) and, occasionally something completely different for a change (I tried flying trapeze last year).
Click to expand...
 
And also, would you not reduce your quick acting by any amount before exercise, or is that just for more longer lasting exercise?
 
DiabeticDi said:
Brilliant, just what I wanted, so helpful. One question...if while I am at the guym I test and I am too low, what is the best thing to take? Glucose tablets? Lucozade?
Click to expand...
Whatever works best for you.
Personally, I use GlucoTabs because they are easy to carry and measure how much I take,
On the downside, they are not easy to swallow (i came close to splattering a mouthful of GlucoTabs and water across a Spin class room).
 
DiabeticDi said:
And also, would you not reduce your quick acting by any amount before exercise, or is that just for more longer lasting exercise?
Click to expand...
I have never reduced my quick acting insulin provided my BG is in the 6 to 8 range before I start.
For me, it is more important that I have no quick acting on board when I start.

This is much easier to manage with a pump where you can reduce your basal for the period of the exercise.
 
DiabeticDi said:
Brilliant, just what I wanted, so helpful. One question...if while I am at the guym I test and I am too low, what is the best thing to take? Glucose tablets? Lucozade?
Click to expand...

Jelly babies for me, but they're what I use for all fast tweaks. The important bits are does it contain glucose, can you get it in you quickly, and is it tasty enough for you to want to get it in you. Then less important but still worth considering are availability, cost, and size of dose. So glucogel/hypogel would work, but might fail on cost + availability + taste. Glucose syrup for baking is cheaper and probably easier to find (though a little bit less effective instantly), but would fail on taste. Wine gums are cheap, easy to find and tasty, but I find they take longer to chew. So I have jelly babies, transferred from a big bag into little ones so I can easily carry while running and don't have a big open bag lying around going off.

But that's me. Others have different tastes. Go with what feels good.
 
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evilclive said:
The important bits are does it contain glucose, can you get it in you quickly, and is it tasty enough for you to want to get it in you.
Click to expand...

Ah, you have more will power than me. A little carb goes a long way for me (one glucotab raises my blood sugar by 2.5 ish) so it's important for me to have something that I tolerate but do not like to much. Otherwise a case of the hypo munchies can have a devastating effect on my bg!:). I carry glucotabs because I have no trouble chewing them and I can refill the tubes (which are easy to reclose so don't leak over my handbag or pocket ) with the handy containers of 50.
 
I have just got back from the gym and remembered another tip...

Typical gym sessions (not classes) consist of cardio and weights. As these two types of exercise can have opposite affects on BG, they can been used to regulate BG.
If i test before exercise and find it is towards the top of the 6 to 8 range, I do the cardio first.
If I test and my BG is quite low (under 6 but not hypo), I would do a little warm up and then straight into weights to bring my BG up. Then I am at a good level to do the cardio afterwards.
 
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