Insulin: To Spike or Not to Spike?

www.flexonline.com/nutrition/insulin-spike-or-not-spike

spiking insulin didn’t reduce protein breakdown, and it didn’t enhance anabolic signaling pathways. The insulin spike didn’t even increase muscle blood flow! What appears to have happened was,because they used a protein source(whey) that has already been shown to maximally stimulate post-exercise protein synthesis as well as increase insulin levels, no further anabolic effect was possible even from an insulin spike. The insulin level triggered by whey alone was able to maximally inhibit protein breakdown, increase blood flow, and activate anabolic signaling pathways.

The take-home message is: Just make sure you are getting some high- quality, easily digested protein into your gullet immediately after your workout. Whether you ad carbs or not will not have a significant effect either way.

Have a look at this article linked below from the Journal of the International Society of Sports Nutrition. It discusses data from studies about both post workout protein and carb consumption and is the the latest in depth peer reviewed article on thi topic that I have seen. Despite all 80+ studies listed as references, there is no conclusive final answer about whether carbs post workout are necessary.

Comparing protein synthesis for a few hours after post workout shakes might show no immediate increased protein synthesis in that study mentioned on flexonline but there are many other factors that could affect overall body composition, and then what about when you add anabolic steroids to the equation or compare results in men who carry considerably above average muscle mass or bodybuilders who need much more glycogen than the average happy jogger.

There's lots of good logic on both sides of the argument. Until science catches up and makes up it's mind I will go with the anecdotal evidence from years of top bodybuilders experiences and feedback which says results are better with post workout carbs. If I'm wrong then at least I look good being wrong haha.

Journal of the International Society of Sports Nutrition 2013: Nutrient timing revisited: is there a post-exercise anabolic window?