Someone linked me to this thread, and I'm glad to see a good topic being brought up.
I remember when Sam was emailing me. It was a very busy day and if I had known it would be posted, I would have gone into a bit more detail.
Insulin is a very misunderstood hormone.....the problem with the way most people look at things is that it is much easier to take a linear look at things and leave it at that....leaving out all the minor things that lead to a major impact on outcome.
If anyone is interested in probability, this analogy may make some sense.
If you ride the bus each day, and know the bus schedule sends a bus every 10 min or so, most people assume to wait an average of 5 minutes for the bus.
Some days you'll get there closer to when a bus arrives, and other days you'll get there further from when the bus arrives. But, the average time for 10 min should be 5 min.....
This is incorrect though. YOu will wait MORE than an average of 5 min. This is because the bus doesn't come at exact 10 min intervals. Sometimes it takes 15 min, and sometimes it only takes 5 min between buses.
The CHANCE of you showing up at the bus stop during one of the greater than 10 min intervals is higher than you showing up during one of the lesser than 10 min intervals. This then sets the "average" as longer than 5 min.....Murphy's law at its finest.
What does this have to do with bodybuilding?
Dextrose (dextrorotary-glucose, or D-Glucose) will spike insulin HIGHER than WM.
Insulin is a storage hormone. It drives nutrients to the muscle, yada yada.
BUT, and this is where the analogy (weakly) comes into play. THAT DOESN'T MATTER with WM.
WM is a lower GI carb. This throws people off.
People know dextrose spikes insulin, and know that WAS good. The problem is that dextrose - or any sugar - DOES spike insulin.........WHEN it gets to the blood stream.
The PROBLEM is its HIGH osmolality/LOW molecular weight. WHEN....WHEN it gets to the bloodstream, it spikes insulin and drives nutrients to storage.
But, because of the LOW molecular weight and HIGH osmolality, it TAKES TOO LONG TO GET TO THE BLOOD STREAM.
By the time Dextrose has finally stopped pooling water in the abdomen and allowing full gastric clearance, WM is ALREADY RESTORING GLYCOGEN.
WM has already reached the small intestine, has already cleaved many monosaccharides from its molecular structure, and those sugars have reached the bloodstream, and have been taken to the cell by insulin.
Activated insulin receptors regulate protein molecules in the cell that allow the sugar to be transported into the cell.
Another way the WM works is fairly interesting.
A BIG load of glucose DECREASES gastric emptying (as stated/shown by its high osmolality).
But, WM can speed gastric emptying by more than just its low osmolality.
Because it reaches the small intestine quickly, it sends sugar into the blood in smaller amounts initially.
These raise insulin, resulting in the potential for very mild initial hypoglycemia (as insulin draws the glucose to the cell, before glycogenesis has been completed).
This ALSO SPEEDS UP GASTRIC EMPTYING in response to the initial hypoglycemia. (Ever notice people often mention an initial mild sensation of hypoglycemia? This isn't from a major rise in insulin. This is from the initial trickling of sugars cleaved from the WM into the bloodstream causing the sensation that is noticed.....a sensation that speeds up gastric emptying even quicker)
We tend to get WAY too in-depth into things that simply do not matter. What does matter is that WM reaches the cell quicker than Dextrose.
Insulin is necessary for this transport.
But, insulin isn't only produced in response to huge amounts of blood sugar. Insulin is produced on the level needed for nutrient uptake.
The Dextrose just piles into the bloodstream all at once. This causes a higher insulin spike.....does this matter?
As I said above, insulin binds to the receptor on a cell and activates it. That's it.
It is a full, activating agonist.
Larger amounts of insulin are needed for dextrose, because there are more cells that need their insulin receptors activated all at once.
But, all things being equal, 100g of WM and 100g of dextrose produce the same rough total insulin amount. Dextrose's effect on insulin just takes much longer to get started.
Here's some more over-analytical, pointless information about insulin.
Insulin is a CNS depressant.
We can understand this because huge carb meals can make us sleepy.
But, low blood sugar (which raises insulin) can initially show its effects as somatic stimulatoin. (you feel jittery and speedy).
Insulin (initially) acts on the adrenal medulla, causing Epinephrine to be released.
This stimulates the liver to release glycogen to raise blood sugar levels.
Fructose (which could stop this signal to the liver) cannot cross the blood brain barrier.....so, a compensatory response originates in the CNS.
