[quote]Christian Thibaudeau wrote:
HG Thrower wrote:
Christian Thibaudeau wrote:
- I actually do not recommend post-workout carbs anymore. Catecholamines released during the training session reduces the response to insulin. So post-workout carbs are not super effective… not moreso than only post-workout protein.
Whoa! Do you have any science or data to support this? We’ve been told for years that post-wo carbs are king for growth and insulin management, (Surge Recovery, etc.) with lots of studies to support. This would be a HUGE departure from that. (Not being a naysayer here, its just kind of a shock to hear) Or is there a difference between carb timing for minimizing bodyfat vs. maximizing muscle gain?
I must admit that the evidence is indirect. What has been found is that catecholamine are released during intense exercise and that they stimulate the release of glucagon. Glucagon is the antagonist hormone to insulin. Two antagonist hormones are rarely released to a significant extent at the same time. And if they are, they often counteract each other.
So even if insulin was released (it is to some degree) it doesn’t do its job quite a well (or at all) because of elevated glucagon levels.
''Glucagon and plasma catecholamine responses to graded and prolonged exercise in man
H. Galbo, J. J. Holst and N. J. Christensen
Glucagon concentrations correlated significantly with norepinephrine and epinephrine concentrations during prolonged and with epinephrine during graded exercise. Although increments in catecholamines were similar, the glucagon secretion was larger during prolonged than during graded exercise. While increments in catecholamines might explain increased glucagon secretion during graded exercise, they cannot account completely for the rise of glucagon during prolonged exercise. ‘’
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Hi Christian,
I was always taught that insulin is much more “potent” a hormone than glucagon. Meaning, when considering an average healthy individual high plasma levels of insulin will always blunt glucagon secretion. This ability is through several mechanisms, of both glucose and insulin. Glucose is actually believed to be able to directly blunt the release of glucagon by lowering the concentration calcium ions of individual alpha cells independently of somatostatin and beta cell factors. There is also the belief now that insulin (although I dont believe it has been "proven) directly binds to alpha receptors. This is significant because blood flow in the pancreas is from the beta cells and moves towards the alpha cells, which would cause a greater inhibition of insulin to glucagon and not vice versa.
There is also the secretion of amylin from the beta cells, which have proven to suppress glucagon, as well as possibly the incretins. Plus knowing that amino acids stimulate glucagon secretion as well, I would imagine that having glucose to shift the ratio of insulin/glucagon to the pro insulin would be beneficial, however I do think that all the carbohydrates from the during/pre workout would be more than sufficient. Insulin is also capable of reversing glucagon stimulated phosphorylation while I dont believe glucagon is capable of an analogous action.
I obviously really respect you and I am certainly not trying to be a smart ass or try and debate you or anything like that, just giving by tidbit of knowledge the way I learned it, in an attempt to understand the situation as a whole better. Anyways, I appreciate and respect all the time you dedicate to the site, and helping with training, nutrition etc, so thank you.