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  1. #1
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    On the bike Nutrition - Hypoglycemia? Or something else?

    Hey folks.

    Ok, i'm not sure what's going on here, but was wondering if anyone can shed any light or explanation. This is something i've experienced for a long time but realised after speaking to others that it isn't right.

    I've noticed that during a long ride where I eat on the bike, if I consume things such as off the shelf energy drinks, gels, energy bars etc that after consupmtion I experience an immediate lift in energy which lasts a short time (i.e 1-2mins) and is then followed by an energy slump which seems to slow me down (dependant on how much I consume at once), before I return to "normal" i.e back to the state that I was before I consumed anything.

    Now, the strange thing is, if I consume fruit during the ride (bannanas, dates etc) I get a steady energy boost without the crash a couple of mins later. One small bannana may last me 20-30mins or so depending on the intensity of the exercise (the energy from the fruit wears off steadily, too).

    Why is it these manufactured gels/bars/drinks don't seem to give me energy and just slow me down? I mentioned this to the guys I train with and they said that something isn't right if i'm perceiving so many ups/downs in blood sugar. I also get this varying energy feeling throughout the day (likely following meals etc) - it's the way I always have been for as long as I remember.

    I've been tested for Diabetes already so it's not the issue, and my blood tests came back fine. On self diagnosis, i've put it down to hypoglycemia. Or could it be that I just don't tolerate some forms of sugars/grains very well?

    Thanks!
    Elite XC turned Cat1 Road Cyclist

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  2. #2
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    No ideas? Or am I just a freak of Nature
    Elite XC turned Cat1 Road Cyclist

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  3. #3
    just another gosling Carbonfiberboy's Avatar
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    Freak o' nature, all right.

    #1 thing, when I eat high GI food on the bike, nothing happens for about 15 minutes. Same with aspirin, etc. Takes a while to get stuff into my bloodstream. So if you're getting an "immediate" lift, you're different from me, and I definitely have hypoglycemic tendencies.

    #2 thing, high GI food lasts me over an hour, if I eat enough of it, but I usually don't consume that much, eating about every 15 minutes by preference. So I have a lot of overlap between consumption and use cycles, and don't see any blood sugar swings unless I don't eat for a long time. I can eat 130 GI food and do 1.5 hour pass climbs without eating anything, but I'll need to eat a bunch at the summit. Luckily there's usually a descent after a summit and time to get digestion started if the GI is high enough.

    #3 thing, an immediate slump after eating could be due to eating too much, moving blood supply from legs to stomach. Don't eat so much at a time. 1/4 of a Clif bar every 15 minutes, for instance, or a gel every 20 minutes. You have to keep it coming, but keep the quantities down.

    #4 thing, it's also possible that you just can't tolerate some foods. Corn or wheat allergy? Almost all energy drinks/food have corn product in them, usually in the form of maltodextrin. I know Clif bars are wheat free, but don't know about corn. Worth looking into. Try taking both wheat and corn out of your diet and see if it helps. If that doesn't help, try consuming very high GI foods on the bike, IOW maltodextrin, and consuming only low GI foods off the bike.

    Maybe you need to eat more fat. Many people mistakenly believe that a low fat diet is healthier. This can mess with your pancreas and get it cycling too fast - hypoglycemia. Put a log on the fire: fat.

    So there are many things to try.

  4. #4
    Senior Member AnthonyG's Avatar
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    Yes this does sound like REACTIVE hypoglycemia to me. I don't handle strong sugars well either and I've also had numerous tests for diabetes which all come back clear but still I do suffer from reactive hypoglycemia. Definitely try more fat in your diet.

    Anthony

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    Thanks, Carbonfiberboy + AnthonyG.

    Yeah, it seems I am very blood sugar sensitive. Or at least sensitive to some foods/sugars. I also get bad low blood sugar episodes if I don't eat every 2-3hrs (feeling of weakness, lethargy). After I eat I notice a blood sugar lift straight away. Also, on the bike, i am only talking nibbles, so not chowing down like a whole cliff bar at once. 1/4 of one at most at a time and I get these symptoms. My energy drink has maltodextrin. I don't normally use the stuff, but at a recent training camp I noticed it was doing the exact same thing to me, a high which lasts for a very short time followed by a crash which lasts a lot longer than the high. For this reason, I just stick to water + electrolytes or fruit juice.

    Interestingly enough, i've ridden for 60miles before on an empty stomach (no breakfast) and just water/electrolytes with no ups/downs. I felt fine. I don't make a habit of that though. It's basically as soon as I start eating for the day i'm up and down like a yo-yo. I try to add lean protein/good fats to each meal to even things out but not sure if it makes much difference, although I will experement with more fats. Tried low carb previously and just had zero energy, so I defo need carbs. It just seems that I don't tolerate some of them well. Interestingly enough, Oats seem to be one of the worst carb sources for me. If I eat Oatmeal for breakfast, i'm completely lethargic, weak and experiencing brain fog 1 hour later.
    Elite XC turned Cat1 Road Cyclist

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  6. #6
    just another gosling Carbonfiberboy's Avatar
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    That's very interesting. I used to tolerate carbs just fine, but went on a very low fat diet and developed the exact symptoms you describe, plus I hyperventilate, sweat, and cannot make decisions. I had a glucose tolerance test done and was described as pre-diabetic. The diabetes nurse was the one who told me to "throw a log on the fire." So I kicked my fat and protein consumption way up and gradually got better. I don't have any problems on the bike, like you do, but off the bike I have to take a nap after lunch and otherwise have to be very careful of carb-only foods. Otherwise, I can now pass for normal.

    The on-the-bike problem doesn't exist if one doesn't ride very long at a time. One can go a couple of hours on just about anything, including as you have found, nothing. The reason you can go a long time before breakfast is that your body is in a special state after awakening and holds blood sugar levels very even. A Type 1 friend of my told me this, but I can't remember what he called this state. He always goes out the door without eating.

    If you want to ride longer or stronger, you need to consume ~180-270 cal./hour. Digestive issues usually mean these are high GI carbs. You can try this: eat the high GI carbs, but much more frequently. You have to eat more before you get the let down, while you are still in the up phase. Does this make sense? So smaller quantities, much more frequently. You want the up phase to be continuous. That's what most aggressive riders experience. Take a gel and attack. And you don't want your pancreas and blood sugar to be cycling all the time. That's bad.

    I have a strategy of taking 15g of whey protein about 1/2 hour before every meal. This seems to smooth out the blood sugar bump that the meal will produce. After a ride 25g whey protein and enough carbs to get me on my feet.

    I also include whey protein in my high GI on-bike food. Maybe that helps, too. You can try drinking Ensure on the bike to get a similar effect. Many riders will use almost nothing else. Just put a couple of bottles in one water bottle, plain water in the other. That'll probably get you up the road for 3 hours.

  7. #7
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    Hey Guys.

    Just thought i'd let you know - had a bit of a breakthrough! In all my time as an athlete, i've never taken a multi-vitamin. I started taking Centrum Advance just this past week and amazingly all of these problems have dissappeared! My energy levels have soared too, I can't believe i've cured it with a simple Multi-vitamin/mineral tablet! I feel nice and "level" all day! My guess is that I had some sort of mineral/vitamin deficiency that was causing these problems? What do you think?
    Elite XC turned Cat1 Road Cyclist

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  8. #8
    Senior Member AnthonyG's Avatar
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    Quote Originally Posted by paulclaude View Post
    Hey Guys.

    Just thought i'd let you know - had a bit of a breakthrough! In all my time as an athlete, i've never taken a multi-vitamin. I started taking Centrum Advance just this past week and amazingly all of these problems have dissappeared! My energy levels have soared too, I can't believe i've cured it with a simple Multi-vitamin/mineral tablet! I feel nice and "level" all day! My guess is that I had some sort of mineral/vitamin deficiency that was causing these problems? What do you think?
    Its possible. Many vitamins and minerals are important cofactors in countless enzyme reactions that are critical to the bodies functions and being deficient will slow down these reactions. Supplements aren't the best way to get these vitamins and minerals if it can be avoided (I take a couple like vit D outside high summer and magnesium) so look hard at your diet. Also if you have recently cut some sugar out of your diet maybe the benefits of this have kicked in. Your body doesn't always respond to dietary changes immediately.

    Anthony

    Anthony

  9. #9
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    Thanks Anthony. I think for the most part, my diet is pretty good. I focus on getting a decent amount of fruits and vegetables each day, along with carbs and quality proteins. I don't tend to eat much in the way of foods containing processed sugar, or anything junky out of a packet. Of course there are times when i'll eat some rubbish - perhaps if i'm craving it after a race or hard training, but I try to keep this to a minimum.

    Interestingly, I also feel like I have more energy since i've started the multi, and I wake up in the a.m feeling a lot clearer than usual. I also notice that my sweat rate is a bit higher - my body just feels more willing to produce an effort on the bike, I presume this is the minerals in the multi-vitamin allowing energy in my body to be utilised better. Just did 35miles on the rollers this a.m and never felt better! I assume it wasn't magnesium that I was deficient in, as I was already taking that. Perhaps it is calcium as I don't eat any dairy products?
    Elite XC turned Cat1 Road Cyclist

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