Insulin, Glucose and Muscle Growth

Hormones play an essential role in building muscle, burning fat, and sculpting the physique you've always dreamt of. The hormone that immediately jumps to mind, of course, is testosterone, the “king” of anabolic hormones. But, there’s another hormone that’s even more powerful than testosterone and holds the key to unlocking your true anabolic potential — insulin.

What is Insulin?

Insulin is a peptide hormone released from the beta cells of the pancreas when there is a rise in the body’s blood sugar level, typically brought on by consuming carbohydrates and/or high levels of protein. It is primarily responsible for regulating blood sugar levels and shuttling nutrients into cells. Your body prefers a certain homeostasis for its blood sugar levels (around 100mg/dl) and if it rises about this equilibrium, insulin is released to “pick up” the excess sugars and store them in one of three areas:

  • Muscle glycogen
  • Liver glycogen
  • Adipose tissue (a.k.a. fat)

Obviously, you’d want those excess sugars to only be stored in your muscle or liver glycogen, but that’s the thing about insulin — it doesn’t discriminate. It doesn’t care whether it’s helping increase fat or muscle tissue, it just knows how to make things grow.

In this way, you can think of insulin as a weapon — it can be used for good (muscle growth) or evil (fat gain). What dictates the outcome of insulin’s actions is dependent upon how you “use” it.

This is why insulin is seen as such a powerful hormone to people training as it drives nutrients into muscle cells to be used as fuel for training and to enhance muscle growth. 

Insulin is strongly linked to type 1 and type 2 diabetes and for good reason. As previously mentioned insulin is released when we eat carbohydrates to regulate blood glucose levels and ensure glucose is shuttled into the correct cells.

If you are inactive and have a high carbohydrate diet you run the risk of becoming insulin resistant which can lead to type 2 diabetes. This is where your body still secretes inclusion but it doesn't know how to efficiently use them, this, therefore leads to increased glucose being stored in fat cells. This is also known as becoming 'Insulin Resistant'


Insulin and muscle growth

Once insulin is released into the bloodstream, it travels throughout the body. When insulin encounters muscle cells, it binds or “docks” to specific receptors on the cell and signals it to “open up”, thereby allowing glucose, amino acids (BCAA and EAA’s), creatine, and other nutrients to enter. This process of nutrient shuttling is the primary reason insulin is so critical to muscle growth.

That’s not where insulin’s role in muscle growth ends though. This anabolic hormone also promotes muscle protein synthesis and increases muscle blood flow and amino acid delivery, all three important attributes required for muscle building. Insulin is also anti-catabolic (prevents muscle protein breakdown). On top of that, insulin increases the activity of certain enzymes (such as glycogen synthase) which trigger glycogen formation in your muscles, enhancing performance, muscle size, and recovery.

Insulin is key to muscle growth and is where the recent 'pre-workout muffin' phenomenon has come from to release insulin just prior to training. 

Now let’s take a look at insulin’s role in fat storage

Insulin and Fat

Insulin isn’t all good, it can equally work against you and increase body fat if you’re not careful with your diet. When insulin is released, this signals your body that it has been fed, effectively shutting off your fat burning. Since you just ate, your body doesn’t need to run on its stored fuel anymore and will go about using the fresh nutrients you just consumed for fuel.

On top of that, insulin also works on your adipose cells similar to your muscle cells in how it “opens the floodgates” to allow glucose in to increase size. This increased uptake of glucose and fats leads to additional body fat storage. The more fat you store, the less you burn off, so you can see how keeping your insulin levels chronically elevated throughout the day isn’t exactly ideal for sculpting an ideal physique.

Insulin and Glucose

As we stated up top, insulin’s primary function is to lower blood glucose levels in the body when there is a rise in blood glucose. Provided you have a healthy metabolism, your body will absorb the excess glucose and transport it to your cells. However, this can also lead to an energy crash due to consuming too many simple carbohydrates or if your glucose tolerance is impaired. The crash is linked to low blood sugar levels, a.k.a. hypoglycemia.

When you have a crash, you basically feel like you’re completely zapped. Aside from feeling completely drained, your hunger also soars, which can cause you to overeat, leading to additional fat gain. There are a couple of ways you can limit these crashed throughout the day:

  • Limit simple carbs (sugars) to specific times (i.e. pre and post workout).
  • Use a premium quality glucose disposal agent (GDA) to ensure uptake of carbohydrate into muscle cells 
  • Building Muscle and Burning Fat

So, the big question on your mind is how do you manipulate insulin to work for you and not against you. Well, it’s going to require some careful planning on your part. For the majority of the day, you want to limit blood sugar spikes and insulin release. This will allow your body to run on its stored fat.

The times you want to increase the amount of insulin you secrete is around your weight training. This way, the insulin that is released will use the excess glucose for muscle glycogen storage and not fat. Following weight training, liver and muscle glycogen are depleted, meaning they’re primed to absorb a lot of glucose. Now more than ever, don’t skimp on your carb intake. This is when you can maximize muscle growth and make carbs and insulin enhance muscle growth.

Glucose Disposal Agents — Making Insulin Work for YOU

Mastering insulin is a tricky endeavour. Eat too many carbs or proteins at one sitting, blood sugar soars, and insulin is released, setting you up for unwanted fat gain. CSN stock a range of GDA's by various brands such as DedicatedGenetic, Project AD and ProSupps.

They all mimic's insulin’s effects on the muscle cells, ensuring all those tasty carbs you eat go towards building muscle, not fat. Take them pre-workout or post workout to maximize the anabolic response or any other time you’re having a carb-heavy meal (i.e. cheat meal) to limit spillover and fat gain. With CSN, the days of fearing carbs are no more, insulin (and carbs) are now your best friend to body recomposition.