A Guide To Insulin And Insulin Sensitivity
Years ago, insulin was only discussed in reference to diabetes. Insulin is the hormone that drives glucose out of the bloodstream and into cells, and diabetes is the loss of the ability to control blood glucose levels. Yet insulin is so much more than a hormone that controls glucose. For one, it's highly anabolic, which means it's critical for building muscle.
Insulin also has a dark side, because it can increase fat storage. The challenge is to learn how to spike insulin to optimally recover from workouts and grow, while also blunting it to stay lean.
In this blog we are first going to look at what it is that insulin actually does, what insulin sensitivity is and then we will give you 8 tips to help use insulin to your muscle building and fat burning advantage.
Insulin’s Role in the Body
Insulin And Muscle Growth
Insulin is actually a protein, and it is produced and released by the pancreas whenever you eat carbs, protein, or both (that is, if the pancreas is working properly). Yet unlike the proteins that are the physical building blocks of muscle, this is a functional protein, much like growth hormone.
Like all other proteins, insulin is a chain of amino acids strung together. But the way this protein chain is folded makes it act more like a signaling mechanism than a building block.
From the pancreas, insulin enters the bloodstream and travels to various tissues, including muscle tissue. The muscle fibers (or cells) are lined with insulin receptors, similar to a docking station. Once the insulin molecule docks onto the receptor, it signals the muscle cell to open up gates. This allows glucose, amino acids, and creatine to enter the muscles. This process is a major reason why insulin is so important for building muscle.
Another reason is that when insulin docks onto the muscle cells, it instigates biochemical reactions in the muscle that increase protein synthesis, which is the building of muscle out of the amino acids that are entering the muscle cells. In addition, insulin also decreases muscle breakdown, which further enhances muscle growth.
Insulin also indirectly aids in muscle development by causing the blood vessels to relax and dilate, allowing greater blood flow to the muscles. By increasing blood flow, insulin can help get even more nutrients like glucose and amino acids to the muscles. This is why you'll see bodybuilders pounding simple carbs on contest day. Not only does the corresponding spike in insulin drive the carbs into the muscles to keep them full, it also boosts vascularity.
Insulin And Body Fat
Insulin's release from the pancreas signals the body that it has just been fed. Since the body is always trying to spare energy, it halts the body's burning of stored fat, instead turning to the nutrients that have just been ingested. Meanwhile, insulin also works on fat cells similar to how it works on muscle cells, signaling the gates to open and nutrient storage to commence.
An increase in the uptake of glucose and fats causes the body to store more body fat. As long as those insulin receptors work as designed, a spike in insulin levels clears out the majority of the glucose in the blood, pushing it into muscle and fat cells.
This lowers blood glucose levels in an orderly fashion, if someone has a healthy glucose metabolism, but it can also lead to a crash—either because the person's glucose tolerance is impaired, or too many simple carbs were consumed at once. The low blood sugar that results from a crash is known as hypoglycemia.
A crash will make you feel like your energy levels have been zapped. Not only is this bad for your general well-being, but it's bad for your physique. What's more, when your energy crashes, your hunger soars.
Insulin and Carbohydrate Usage
First off, we need to know that there are eight essential amino acids and eight essential fatty acids required for life. These same nutrients are used all over the body for normal and constant metabolic processes such as repair of hair, skin, bone, muscle, red blood cells. Fat is used for energy purposes, protein only in ketosis.
Carbs on the other hand are not essential for survival, but they provide us with fuel for our brain (unless we are in ketosis), short or intense bursts of activity (strength or cardio), fiber and minuscule but essential amounts of vitamins and minerals which are very difficult to store (unless they're fat soluble), and if they're not used at that time, they are passed through the body very quickly.
This means the main role of carbs is to top up the liver and muscles which are not as big a store as some people would realize, especially if we don’t have a lot of muscle mass to begin with.
So What Is Insulin Sensitivity?
Insulin sensitivity refers to how your body responds to the hormone insulin, and is directly related to how productively it handles the carbohydrates that you consume. Those with high sensitivity (fast response) have better blood sugar regulation, allowing the body to store glucose in muscle tissue rather than in those fatty love-handle areas.
On the other hand, poor insulin sensitivity may result in the overproduction of insulin, causing the body to play catch-up to control increasing blood sugar levels and force the storage of glucose as fat in the body.
Chronically poor insulin sensitivity can lead to a number of conditions like type-2 diabetes and cardiovascular disease, so it's important to keep your body-insulin connection strong and thriving!
Generally, we want to enhance our own degree of insulin sensitivity, for fat loss as much as for muscle gain.
It's important to note that Insulin is sensitive to both carbohydrate and protein consumed, but not fat. However, of all the food sources, it's the higher, simple carbohydrate meals that elevate Insulin levels the most after a meal.
Revamp Your Diet!
A rethink of your diet might be in order if you eat a lot of ‘traditional’ western foods including breads or other baked goods, "healthy" fruit juices, canned fruit, lots of rice or pasta, sauces or condiments with sneaky added sugars…
Follow these 8 tips to make sure your body and insulin play well together for the best results!
Step 1: Tighten the Reins On Refined Carbs
Reducing your refined carbohydrate intake is a game changer for controlling your insulin levels. One of the primary reasons people develop diabetes over time is their overconsumption of excess refined carbs/sugars, which causes their pancreas to continually pump out more and more insulin. We are not saying this to fear-monger, there is nothing wrong with having a donut or some pizza every now and then. BUT the majority of your carbs should come from vegetables, some fruit, (whole)grains and starches. Simple carbs, such as those mentioned above which are digested easier and released into the bloodstream quicker are best placed around workouts (when we do actually want to spike insulin a bit more).
Step 2: Have Some Healthy Fats
Another way to increase your insulin sensitivity is by optimizing the rate at which your body processes carbohydrates and directs them to muscle tissue, and this is done by eating plenty of healthy fats.
Diets that are loaded with trans fats tend to encourage poor insulin sensitivity, while the reverse holds true for those who consume plenty of monounsaturated and omega fats. The best sources of healthy fats include olive oil, flaxseed oil or flax seed, avocados, seeds, nuts and nut butters, and fatty fish or whole eggs.
If you can consume small amounts of these fats every day, making sure not to overindulge, you'll be one step closer to promoting an iron bond between your body and its insulin.
Step 3: Consider FOOD Timing
This is also helpful for when you DO want to have simple carbs. Having some avocado BEFORE eating your slice of toast is going to have a vastly different reaction on your insulin than the other way around or eating some yogurt BEFORE having that donut or even before having fast digested fruit…
This means the order in which you eat your food matters! Always try to have some healthy fats, protein or fiber/ vegetables before indulging in those simple carbs (except around workouts).
Step 4: Consider MEAL Timing
It is hard to give a general recommendation for this, as some people are going to do a lot better with only 2-3 large meals throughout the day, whereas others’ insulin levels and wellbeing is going to be better when eating more frequently.
What is clear however, is that constant snacking or constant elevation of insulin levels (for example, breakfast - sweet beverage - snack 1- gum - lunch - gum - snack 2 - sweet beverage - snack 3 - dinner - snack 4…) is not optimal for insulin levels. It is also clear that fasting for at least 10-12 hours overnight is beneficial for everyone in order to give your pancreas and digestion a bit of a break.
Step 5: Focus On Fiber
Eating a good amount of fiber isn't just for digestion and regularity. Fiber-rich meals also slow the release of carbohydrates into the blood, allowing for a more effective insulin response.
Many high-fiber foods like fruits and vegetables also provide the body with numerous vitamins and minerals to further improve your health and ward off disease.
Remember, fiber is also very beneficial for fat loss because of its ability to help pass unnecessary ingredients out of the body instead of allowing them to be stored as fat!
Step 6: Perform Depletion Workouts Every So Often
From the workout side of things, one thing that you can do to enhance the rate at which your body shuttles glucose into the muscle cells is by really pushing yourself on a lift or your cardio workout every so often (~1-2 per month perhaps).
By depleting your muscle glycogen levels, you'll create a large "sinkhole" into which glucose can move. When you're in a very glycogen-depleted state, your body will instantly suck that sugar right up and put it into the muscles, staying far away from your body fat cells.
Don't perform depletion workouts or lifts too often, as this may seriously interfere with your training performance over time (diminishing returns…).
Step 7: Stay Active
The last step to enhancing your insulin sensitivity, is making sure to keep moving every now and then throughout the day. Most people hit the gym regularly, but they succumb to long periods of inactivity during the rest of their day. Even just getting up and walking to the bathroom or to get a drink once an hour is better than nothing. Aiming for about 8-10k steps a day can be helpful in order to encourage movement throughout the day.
Step 8: Your Insulin Loves Healthy Body Fat Levels
Getting lean itself is another important way to increase insulin sensitivity. People with healthy body fat levels have a greater ability to gain lean muscle mass. The primary reason is this--they can send more of those excess calories to the muscle cells, where it provides energy for muscle building and growth, rather than to be stored as fat. Yoyo-dieters or those with too much excess body fat generally tend to have poorer insulin sensitivity levels.
Of course this piece of knowledge is not necessarily helpful for the person trying to LOSE weight, but it should be an encouragement to maintain healthy body fat levels as best as possible.
Potential Hazards From A Caloric Deficit
Don’t take it too far! If you do not provide your body with adequate nutritional support in the long term, you'll actually make things worse. Stress hormones affecting our pancreas and insulin production is one reason. Another reason is that if the body is without certain nutrients long term, it has to choose between switching off certain processes temporarily or leeching what's needed from somewhere else in the body. This would mean further catabolism/ breakdown when you are already in a catabolic state from dieting and training. This puts even more stress on the body by asking it to provide further breakdown in another area to sustain itself, which is just more stress added to the system.
To summarize, insulin is a super helpful hormone for muscle growth and burning fat. In order to work WITH our insulin and not against it we want to release energy from carbs slowly, most of the time,
→ by way of high quality carbs paired with healthy fats and protein
→ by way of healthy activity levels
→ by way of reaching and maintaining healthy body fat levels.
