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Exercise options and how it affects BG levels

N

nannyg123

Well-Known Member
Messages
49
Location
Norfolk
Type of diabetes
Treatment type
Diet only
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whingers
Hi all
Since diagnosis Jan 14 I've introduced exercise and now regularly swim (breast stroke head in water) for 40-45 mins 4-5 times each week (mile each time). My levels have been fairly good - before and after falling into range of 5-7. The pool is not far away but I thought it would be good to try different exercise so I don't get bored and also nice to do somewhere where I don't have to get the car out. I live in the country and like to walk but feel daft brisk walking the country roads without a dog (and I'm not getting one). So, I dusted my bike off this morning and decided to go for a cycle ride. I'd forgotten how hilly it is here (more like long slopes but it felt so hilly). I only did 20 minutes at a steady pace - picked the shortest round the block route as it was a test run today. Fasting this morning BG was 7.1 (usually around 7 - working on this). Post brekkie (Greek yogurt with blueberries and omega sprinkle) 6.7. After cycle ride 9.3!! 30 mins later 7.7. Wherever I cycle from home would involve hills/slopes so does this mean cycling is out for me? Or should I have had different brekkie to cope with the higher cardio exercise? Any advice greatly appreciated.


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Sounds like you had a liver dump whilst cycling - your body demanding a bit more energy from the store quite possibly due to a different form and intensity of exercise.

I note that your normal length of exercise is 40-45 minutes, and also that your BG dropped back quite quickly after your 20 minute ride.
So perhaps you are seeing the same response as when you swim, but just testing when you would normally still be swimming?

Nothing obviously dangerous in your breakfast :-)

So I would persevere because it sounds as though cycling is very suitable exercise in your location and could improve your general level of fitness.

Perhaps extend the ride towards the 40 minutes over the next week or so and see if this changes things.

Note that as a cyclist I am somewhat biased.

Cheers

LGC
 
Hi,

There are some really good threads on this subject over in the exercise section of the forum. I only understand the basics (they go into it in much more detail, if you want to settle down with a cuppa and read up I'm them).

However, this is my understanding of the basics - but I hope someone else will pop along and correct me if I get anything wrong! Thanks in advance, whoever you are...

Basically, regular exercise will have both long term and shorter term benefits on you BG levels.

The long term benefits are reduced insulin resistance, increased muscle mass, lower fasting BG levels.

The shorter term benefits are that it raises your metabolic rate for the next 24 hrs (thus lowering your BG levels).

Both types of exercise are good, however, there is a difference between how your body reacts to steady exercise (your swimming) and harder exercise (cycling up hills).

The gentle exercise uses up glucose already in your blood stream, with a proportionate drop in BG.
The harder exercise raises your heart rate more, uses the glucose in your blood up faster, and your body thinks 'ooh, this is hard work, and we're running out of glucose to fuel the muscles. I know, I'll release stored glucose from the liver, to help with this problem...' This creates the rise in BG you observed.

The good news is that your muscles are now all fired up, your metabolic rate has been raised, and your BG will fall again quite quickly, and you will still get nicely lowered glucose levels later in the day.

But don't take my word for it! Map it out with your monitor.

I'm coming round to the idea of an evening trundle, every evening, if I've eaten any carbs. A sort of pre-emptive BG suppression, even before I hit the 2 hour BGtest. It'll be interesting to see what effect it has...
 
Thanks for the advice.
LGT - must admit I hadn't really thought about the fact that BG could be higher whilst still swimming, as I don't test until after showering and driving home, giving time for it to drop after the exercise but I know that swimming is far more gentle exercise, even though I swim quite fast with a forceful kick (woe betide anyone who swims too close) whereas the cycle ride left me breathless and glowing profusely (ladies don't sweat!) for some time afterwards and I could feel my heart pounding. I didn't really enjoy it at all I had hoped that the regular swims would've helped improve my fitness to a level where it was more enjoyable.
Thanks for your really good explanation Brunneria. I'll have a haul through the exercise section for more info. I had wondered if I'd get a liver dump from the more strenuous exercise of cycling and didn't really want to spike BG levels out of range. Will keep it up for a while and see if levels pan out.
Debbie


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Just an additional note - as I am currently re-learning that it doesn't pay to push too hard when starting out on cycling.

If it hurts too much then you don't want to do it again.

I am now trying (on at least some rides) to pace myself so that I am breathing deeply but not gasping.

I am now enjoying the ride instead of enduring the exercise. :-)

Cheers

LGC
 
The problematic effects of hard exercise are most pronounced when you start a new exercise or a new level of difficulty. Once you have adapted to the new exercise, the effects on blood glucose etc become more stable and less dramatic. So persevere with the cycling. :-)

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