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Higher blood glucose after training

damocles10damocles10 Posts: 340
A family member has been diagnosed with type2 diabetes and this has prompt the whole family to take over the counter tests ( Accu-chek ).

Mine is in the safe range around av. 5.9 but after a couple of hours on the bike it can shoot up to 9.9 - 11.3 which puts me in the Hyperglycemia range. Obviously, I will tell my doctor, but is there anyone out there with diabetes who can let me know if it's normal for the higher levels after exercise.

Best wishes

Posts

  • E65RossE65Ross Posts: 23
    Worth getting checked but doubt it's much to worry about....

    exercise ==> glucagon release ==> liver releases glucose into blood stream to meet increased glucose demands for muscles.
  • Definitely have a word to your doctor.

    I was diagnosed T2 in December (family history so was inevitable) and have bought my numbers down to 5.1 (fairly consistently through testing - unless I knowingly eat something that will spike me)

    I notice a rise following exercise - both the intensity and length of time riding has an effect on the numbers.

    Generally it will head towards 7.5 after a particularly strenuous session, but a gentle ride around the neighbourhood helps counter any bad foods I eat (in the same way that walking lowers your BG)
  • damocles10damocles10 Posts: 340
    Thanks for the advice. Due for a check-up so will ask about it.
  • damocles10damocles10 Posts: 340
    I think the important thing is actually how fast it returns to normal after exercise. You always get a spike when you stop because your liver can't instantly stop releasing glucose. But it should drop to normal levels fairly quickly.


    Thanks for your help...I will factor this in.

    Best wishes
  • CrapaudCrapaud Posts: 2,666
    Just curious, Damocles, but do you do a warm down at the end of a ride? I would've thought that a warm down would mop up any spare glucose as the body realises that it's no longer required.
    A fanatic is one who can’t change his mind and won’t change the subject - Churchill
  • airwiseairwise Posts: 180
    I think the important thing is actually how fast it returns to normal after exercise. You always get a spike when you stop because your liver can't instantly stop releasing glucose. But it should drop to normal levels fairly quickly.

    That's the important metric. You will also find there is a spike if you have been building lactate prior to ending the session. If you are sensitive enough to insulin then the spike will be relatively brief and you should be back to basal levels within two hours.

    Where you might encounter an issue then is if you start riding again within the hour, particularly if you've taken on some carbs in the meantime.
  • RutlandGavRutlandGav Posts: 144
    I find this post-exercise spike very surprising, it just shows how we're all different. For me, it's always seemed the opposite, I keep exercising until I start getting the light-headed, listless, not-all-there feeling, which forces me to stop. However, stopping the bike doesn't restore normality - i have to eat some carbs to get back on planet earth.

    Witness my Inspector Frank Drebin bike parking technique (crashing into my own wheely bin because i overestimated distance remaining by a few metres), forgetting to put feet down when stopping, etc.

    I would like to get an Accucheck reading but in that state i'm not capable of operating the device... this is where you need a good friend i guess.
  • CrapaudCrapaud Posts: 2,666
    ...For me, it's always seemed the opposite, I keep exercising until I start getting the light-headed, listless, not-all-there feeling, which forces me to stop. However, stopping the bike doesn't restore normality - i have to eat some carbs to get back on planet earth. ...
    Are you eating enough on your ride? Sounds like the bonk.
    A fanatic is one who can’t change his mind and won’t change the subject - Churchill
  • damocles10damocles10 Posts: 340
    Just curious, Damocles, but do you do a warm down at the end of a ride? I would've thought that a warm down would mop up any spare glucose as the body realises that it's no longer required.


    Hi, I usually do 2 - 3 hours a day 5 or 6 times a week. My speed varies from 18 to 33mph ( when I am really pushing it )....I do cool down after.
  • Diamant49Diamant49 Posts: 101
    Just picked up on this thread - I have T1 diabetes, treated with an insulin pump and I do often get higher BG readings after exercise - though usually only in particular circumstances. Everyone reacts differently, obviously, but for me the major reasons are either 1. higher intensity exercise or 2. carb intake:

    1. high intensity exercise can prompt the release of hormones (eg adrenalin), which increase the body's resistance to insulin, so the effect can be a short-term increase in BG levels. In fact when I feel that I might be going into a hypo, a 10s all-out sprint will usually push the BG levels back up again, for a while anyway. The higher BG levels can last for an hour or two - but even if high when I finish a workout, I will have a tendency to go hypo later, so I don't need extra insulin to counter this, its just a transient feature.

    I usually would experience higher BG levels after a 60-90 minute ride first thing in the morning, when the body is naturally more resistant to insulin - and usually after a hilly ride where I have pushed hard up a number of closely spaced shortish hills (kind of like an interval session). Any distance or effort over 90mins+ will usually lower my BG, unless I have misjudged my carb intake....

    2. which leads on to this - I rarely eat during the first 60 mins of exercise (probably 90 mins before I do), as this invariably results in a high (10+) reading - unless my BG is lowish before I start. A combination of 1 above and intake of too much fast-acting carbs will certainly lead to a high spike for me.

    You certainly need to get checked out by your GP - you could have a high insulin resistance and the only way to check this is by a properly conducted test. If your resting BG is 5.9 you probably don't have diabetes, but you need to know if you are pre-disposed, and despite the media hype you don't even have to be overweight to get T2 diabetes (eg Steve Redgrave).
  • damocles10damocles10 Posts: 340
    Just picked up on this thread - I have T1 diabetes, treated with an insulin pump and I do often get higher BG readings after exercise - though usually only in particular circumstances. Everyone reacts differently, obviously, but for me the major reasons are either 1. higher intensity exercise or 2. carb intake:

    1. high intensity exercise can prompt the release of hormones (eg adrenalin), which increase the body's resistance to insulin, so the effect can be a short-term increase in BG levels. In fact when I feel that I might be going into a hypo, a 10s all-out sprint will usually push the BG levels back up again, for a while anyway. The higher BG levels can last for an hour or two - but even if high when I finish a workout, I will have a tendency to go hypo later, so I don't need extra insulin to counter this, its just a transient feature.

    I usually would experience higher BG levels after a 60-90 minute ride first thing in the morning, when the body is naturally more resistant to insulin - and usually after a hilly ride where I have pushed hard up a number of closely spaced shortish hills (kind of like an interval session). Any distance or effort over 90mins+ will usually lower my BG, unless I have misjudged my carb intake....

    2. which leads on to this - I rarely eat during the first 60 mins of exercise (probably 90 mins before I do), as this invariably results in a high (10+) reading - unless my BG is lowish before I start. A combination of 1 above and intake of too much fast-acting carbs will certainly lead to a high spike for me.

    You certainly need to get checked out by your GP - you could have a high insulin resistance and the only way to check this is by a properly conducted test. If your resting BG is 5.9 you probably don't have diabetes, but you need to know if you are pre-disposed, and despite the media hype you don't even have to be overweight to get T2 diabetes (eg Steve Redgrave).

    Thank you for your reply, very informative.

    One thing I have noticed over the past couple of months is that I get really bad fever like shivers randomly after a ride, they don't last long, 10 mins or so.... I used to get this back in the racing days ( 10 years back when I was peaking at 24 hours a week - I always put that down to not enough recovery ).....I shall mention that to my GP too as they have come back.
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