Insulin is a hormone released from the pancreas after you eat, mainly when your blood sugar (glucose) rises, but to a lesser extent it can also be triggered by the consumption of protein and amino acids.

Though the primary goal of insulin is to keep blood sugar at a homeostatic (normal) level, insulin is also responsible for the uptake of amino acids in order to create new proteins. It also stops the breakdown of muscle protein.

Glucose uptake into the muscle is important, because glycogen (storage form of glucose) is mainly used as fuel for the muscles when exercising, and of course, the build up of muscle proteins and preventing muscle breakdown is great! So what’s the problem?

Unfortunately insulin also promotes the uptake and storage of fat, and the conversion of glucose and glycogen (storage form of glucose) into fat! It also prevents the breakdown of those fat and glycogen stores.

So how do we get all the beneficial effects like proper glycogen fueling and muscle building and repair without triggering the negative effects like fat preservation and storage?

Insulin sensitivity is the ‘speed’ of a cell’s response to insulin being released. Sensitivity is usually high (fast) in most people who are very active, therefore a rise in blood sugar or amino acids will immediately trigger insulin, and the effects of insulin will happen a lot quicker. The focus then for muscle builders is less on the spike of insulin itself, since it is more predictable, and more on what macros you’re using to cause the insulin spike, and when you choose to spike insulin levels in order to maximize your desired effects and results.