I haven't written anything on here for a while as I haven't had anything I felt needed addressing but I am bored tonight so thought I would clear up some common misconceptions surrounding insulin which I believe to be a very misunderstood hormone.
Insulin is a hormone that regulates the levels of sugar in your blood. When you eat, the pancreas senses the rising glucose and releases insulin which sends the glucose to muscles, the liver and other bodyparts. This regulates itself throughout the day and most people need not even know the existence of it.
There are two other functions of insulin that bodybuilders and gym goers tend to take an interest in it for:
1- Stimulation of muscle protein (protein synthesis)
2- Inhibits breakdown of fat (lipolysis)
Protein synthesis
What most people think- Carbohydrates alone are responsible for stimulating insulin.
What is actually true- ALL FOODS you eat stimulate insulin.
It is true that releasing insulin straight after a workout stimulates protein synthesis (although how much impact this will really have without injecting it is up for debate) but there is no need to consume ANY dietary carbohydrates as protein can do the same job. Protein stimulates insulin just fine.
Lets look at a study that measures insulin secretion after a high carb, low protein meal compared with a low carb, high protein meal. Eac totaled an equal amount of calories (675)
As you can see, the high protein, low carb meal actually generated a HIGHER insulin response which is not what most people have been told- and this is with half the amount of carbs.
As you can see here, the high protein, low carb meal was more drawn out and not a spike which some might argue.
My point here is the you do not need to consume any carbohydrates after a workout. Postworkout nutrition has two goals:
1. Elevate insulin to halt protein breakdown.
2. Provide amino acids for protein synthesis.
Protein does both...
An ideal post workout meal would contain both carbs and protein for a higher insulin response and also read Lyle Mcdonald's work if you can be bothered.
Lipolysis
What most people think: High carb diet/meal--->High insulin--->fat storage
What is actually true: Insulin rises and falls throughout the day but the overall calorie intake is what matters.
Here is a great graph I stole from that demonstrates that the net calorific intake is important and not the small spikes in insulin throughout the day.
Over the 24hr period, it will all balance out and you will still be in a net catabolic state if you are in a deficit.
The south beach diet came out 10 years ago suggested only carbohydrates raised insulin which stored fat and this information is very outdated now and people need to look at the research. Looking at the insulin index we can see that some types of fish are more insulinogenic than white pasta, and all the protein sources are very high.
The point I am trying to make here is that ALL foods raise insulin and there is no need to even think about its role in fat loss and it is ironic that the people that go to the gym (generally fit, healthy and not overweight) that have the best insulin sensitivity are the ones worrying about it.
References
http://alanaragon.com/
http://en.wikipedia.org/wiki/Insulin
http://weightology.net/
http://www.ncbi.nlm.nih.gov/pubmed/17413098
