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hypoglycemic tendencies

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Joined: 09 Nov 2006
Posts: 61

PostPosted: Sun Jan 28, 2007 11:32 pm GMT +0000    Post subject: hypoglycemic tendencies Reply with quote

I've had an on going problem with my blood sugar levels plummeting during rides. I'm a nursing student and am very familiary with the S & S of hypoglycemia. I'm not diabetic without any Hx of digestive problems or surgeries

My question is this: is there anything to do besides bring MORE carbo bars with me. I've gotten into a necessary habit of never riding hungry and bringing some sort of caloric intake, but it seems like some days nothing is enough. I've thought about tryin to gain some extra weight to compensate for times of hunger but am not sure if that would be best or even healthy (22 y/o 5'9" 145 ~3-4%body fat)

and also, would there be anything along disease processes or problem physiologically besides the basic inadequate caloric intake, that could promote this tendency?
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The Bike Doc

Joined: 08 May 2003
Posts: 1371
Location: Corpus Christi and Warda, Texas

PostPosted: Tue Jan 30, 2007 8:39 pm GMT +0000    Post subject: Reply with quote


Two things I think about with recurrent hypoglycemia with exercise. You may have an over active response of insulin to glucose which rapidly brings your blood sugars down and makes you go hypoglycemic. The simple sugars such as glucose, sucrose and fructose that are used in sports drinks and energy bars have high glycemic index which means they rapidly raise your blood sugar. These in turn, in individuals who have an overly brisk response to the elevated glucose levels, lead to an overshooting rise in insulin levels that bring the blood glucose level down to rapidly, leading to a crashing blood sugar and hypoglycemia. The other thing that comes to mind is simply inadequate glycogen stores for you lean body mass. You run through those stores quickly in the first 1-2 hours of a ride depending on the intensity. Your body is not quick in switching to producing glucose from you fat and protein stores which lead to hypoglycemia during your transition from glycogen produced glucose to fat and protein produced glucose.

Treatment for both of these problems is similar. The first problem can be managed with using low glycemic index sources of carbohydrates to provide a more slowly released form of glucose into the blood. During long leisurely rides such as bike touring or long endurance building training rides, eating whole grain breads, bagels and crackers are options that can be used. During an intense race were breathing hard and chewing bagels and lox are mutually incompatible, using a sport drink that gets the majority of it's calories from a complex linkage of carbohydrates (sugars) would be a better way to go. Look for maltodextrin in the ingredient label. Both of these techniques can also help with the second cause of hypoglycemia, inadequate or rapidly depleted glycogen stores.

Now if you do endurance races, looooong road rides or bicycle touring, you cannot pack in enough calories from carbohydrates alone. You will need to mix in some calorie dense fats. Peanut butter, dairy products with the full milk fat such as cheese, milk, ice cream, extra butter and/or cream cheeze with a bagel are all fair game. Jim Stamstead endurance racer to the exteme level would drink straight up olive oil on his supper long endurance races. You will also want to mix in some protein to help with sparing of your own body stores of protein (read muscle) from break down. Fortunately most foods that you would eat that have high fat also have high protein (excluding the olive oil chasers!).

In regards to your concerns about something more serious in your body, there are individuals whose pancreas produces too much insulin in response to glucose who later go on to develop diabetes. This is sometimes referred to as metabolic syndrome. A test that can be useful to see if you have a tendency towards over secretion of insulin is to have a glucose tolerance test performed with both blood sugars with insulin levels drawn at fasting, 1 hour, 2 hours, 3 hours and 4 hours. If you hyper-secrete insulin, your blood sugars will initially bounce up but then rapidly come down but you will have excess insulin levels measured concomitantly for the level of blood sugar. Towards the end of the test at 3 and 4 hours you may actually get hypoglycemic. If this test is positive, you should get an evaluation by an Endocrinologist.

A side note: I got my start in nursing before I pursued medicine. God bless you in your studies and endevors. I have never regretted my nursing back ground.

Paul K. Nolan, MD
AKA: The Bike Doc

Last edited by The Bike Doc on Wed Jan 31, 2007 8:29 pm GMT +0000; edited 1 time in total
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Joined: 09 Nov 2006
Posts: 61

PostPosted: Wed Jan 31, 2007 12:23 pm GMT +0000    Post subject: Reply with quote

thank you very much, I'm going to look at getting my own glucose monitoring system that way I can know how low I am getting in these times.

I'm also going to start carrying a cage and bottle with a Gatorade/Accelerade type beverage, along with the normal H20 camelback

I'm gonna look into stock options at powerbar too
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