Hormones, they’re like electricity. Everybody needs them, but no one knows how they work. As the current that drives our whole system, we often take our hormones for granted. That is, until they’re out of whack. At that point, when the “lights” go out, the body suffers hugely.

Since our body’s a temple that deserves the best, let’s take a look at the seven key hormones that give power to our muscles every day. To keep the body in shape, on the move and performing on all cylinders, you must build a healthy hormonal framework for your body.

Today, you’re going to become the master of your hormones.

With this knowledge, you’ll be able to see huge gains by keeping the uber-power of your hormones thrumming at full blast 24/7. No professional care necessary and no blackouts.

Let’s charge on!

First, How Do Hormones Affect Muscles?

During and after exercise, your body is flooded by different hormonal secretions.

To create muscle growth, or anabolism, you need to have a higher number of anabolic hormones in the blood than catabolic hormones.

Anabolic hormones that promote muscle growth are:

  • Testosterone
  • Growth hormone
  • Insulin
  • Insulin-like growth factors (IGFs)

Cortisol is the catabolic hormone that inhibits muscle growth.

To consistently create anabolic states, perform workout routines that emphasize weight training and high-intensity interval training (HIIT) cardio training, instead of low-intensity cardio.


Because cortisol levels are very high after and during long-range cardio sessions over 60 minutes.

If more catabolic (muscle-wasting) hormones find cell receptors, you will actually lose muscle mass to protein breakdown. This happens when muscle stress is excessive, duration of exercise is too great or nutrients are not in sufficient supply.

Only muscle fibers stimulated during exercise are subject to the effects of hormones, good or bad.

And so you can see why it’s important to vary exercises to achieve serious growth. The same gym routine doesn’t work on muscles the same way. For building an already developed muscle, decreasing protein breakdown is the primary goal for allowing gains. You want to see a synthesis of the amino acids actin and myosin instead.

Now that we know we need a favorable balance of anabolic hormones to see muscle growth, let’s talk about each one.

1) ✅ Testosterone

Testosterone releases the growth hormone, which then prompts the release of Insulin Growth Factor (IGF) in the liver. In this way, testosterone is indirectly linked to protein synthesis.

Testosterone affects the nervous system in that it increases neurotransmitters and neuromuscular junctions to enhance muscle size and capacity. With greater neurological efficiency, total muscle force increases.

Workout factors that affect positive testosterone output include:

    • Workouts less than 60 minutes
    • Multiple sets
    • Compound exercises
    • Rest intervals less than one minute
  • Heavy resistance training at 80–90% max

It’s been said that if you want to grow, you really only need to work your legs.


Because your legs are a massive muscle group that use compound movements to squat, deadlift and stabilize with the core. The more muscles you stimulate—and the larger the muscles— the more testosterone you’ll see. If you use machines, swap these exercises for free weights and compound exercises. Using more auxiliary muscles accelerates gains and then add supersets to really blast your body with extra testosterone and the growth hormone. However, it’s less so in women, since women produce only 10% of the testosterone men do. Which is great: women can lift weights and achieve a sleek, toned physique without fear of looking bulky!

2) ✅ Growth Hormone

Growth hormone is what gave you growing pains as a child, as it plays a role in skeletal muscle tissues and other muscles in the body. It also has a function in adapting the body strength given the stresses of exercise.

Growth hormone (GH) is essential for:

    • Improving protein synthesis
    • Allowing amino acid transport
    • Reducing total carbohydrate utilization for energy
  • Promoting lipolysis Growing cartilage

Exercise releases GH at any time of the day, but your body releases the most GH while sleeping, specifically during the four to five deep REM cycles that we have per night. If you fall short on sleep or suffer chronic sleep disruptions, you will miss out on muscles gains. The body uses deep sleep as an efficient time to rebuild and grow damaged cells that cannot be replaced any other way. Reduce your carbs and you can increase your growth hormone.

If excess carbs are consumed, the body secretes high amounts of insulin (which encourages weight gain) and can restrict the output of GH. Fasting has also been shown to increase GH levels. Also, you can’t replace heavy-resistance training with light resistance and raise your levels of growth hormone. Only moderate level (10 reps per minute or more) activity was studied to boost GH serum levels in blood. The more intense the exercise, the more GH is released.

Multi-joint compound movements, like squats and bench presses, recruit more muscle fibers stimulating greater GH secretion. This is also true with shorter duration, higher output workouts … think between 30–40 minutes, instead of 60–90.

It’s clear: boost exercise intensity to boost muscle mass.

3) ✅ Insulin

Secreted in the pancreas, insulin has positive impacts on skeletal muscle, but can also burden you with extra body fat. Insulin functions include: Lowering blood glucose Promoting cellular uptake of carbohydrates, amino acids and fatty acids Promoting fat storage (when at excessive levels) Insulin is a powerful anabolic hormone because it moves amino acids into muscle cells.

Training is known to increase our insulin sensitivity, and this can make it difficult to lose that last bit of belly fat. With high insulin sensitivity, your body creates more of an anabolic effect from carbs and to some extent, protein. Because you’re slimming down, the effects of carbs in your body are amplified and prevent fat loss. This is a function of survival, a protection against indiscriminate muscle catabolism if you, for some reason, had to live on a diet of only carbs (as our ancestors may have done at times with vegetables back in the day).

The solution? Eat healthy fats: coconut oil, olive oil, fatty fish, nuts, etc. Insulin is not sensitive to fats. For this reason, ketogenic diets have become popular for both controlling weight and treating epilepsy.

There is also Insulin-Like Growth Factors (IGFs). IGFs support muscle growth. They’re prominent parts of inducing protein synthesis and blocking muscle atrophy. They help create cartilage cells and are thought to also contribute to maintaining strong bone density.

4) ✅ Cortisol: The Catabolic Hormone

Minimize cortisol levels to maximize growth potential. The body releases cortisol to help the body deal with stress and also to provide it with energy. Problem is, cortisol’s catabolic effects include:

  • Increasing enzymes which degrade protein
  • Transforming amino acids to carbohydrates
  • Blocking protein synthesis
  • Breaking down collagen and ligament tissue
  • Muscle atrophy (in cases of injury)

If cortisol is bound to a greater number of cell receptors, protein breakdown is increased; however, if anabolic hormones such as testosterone and GH occupy a greater number of receptors, protein is enhanced. So how to limit cortisol release in training? Avoid long-duration cardio sessions that deprive the body of proteins and sustain cortisol release. Although, interestingly, weight training that uses high volume, large muscle groups and short rest periods shows the highest levels of cortisol.

So, it appears that exercise that causes the greatest catabolic effect, also causes the greatest GH release as well. Cortisol promotes breakdown, but short-order increases could help with muscle growth.

Why? Because muscles must be broken down in order to grow. Short-term cortisol increases would then facilitate further growth. However, only after sustained intensive weight training.

5) ✅ Thyroid: The Metabolism Hormone

The thyroid hormone isn’t anabolic or catabolic, but it is the primary hormone for metabolism. It controls cell growth, the speed of your metabolism and how sensitive your body is to other hormones. A low-functioning thyroid causes: Low energy Fat and weight gain and difficulty losing water Decreases in muscle building speed Located in the neck, thyroid hormones are released to regulate body temperature and also boost metabolism. If the thyroid gland isn’t functioning properly, these effects are diminished. Thyroid issues are rare, but not unheard of.

6) ✅ Leptin: The Appetite Hormone

Leptin comes from the ancient Greek word for “thin.” Leptin is another metabolism, energy and hunger-controlling hormone. When leptin levels increase, your brain receives a signal that you are “full.” As a result of this signal, your metabolic rate increases to assimilate and store energy in the body.

You need leptin to be in working order or it’s hard to stay lean and fit. The longer the period your body is at a calorie deficit, the slower and lower your metabolism and leptin levels become. A slower metabolism means a lesser chance of losing weight because it tells the body it’s starving. This causes a huge increase in appetite.

If you’re trying to see more muscle by losing fat, don’t fast or your leptin will dip and prevent these losses. It’s best to eat a healthy diet regularly and support your good muscle growth.

Over to You.…

This has been your guide to the six most important muscle-building hormones in the body. As we saw, you need to balance anabolic growth hormones like testosterone and growth hormone against cortisol. If you can maintain a positive balance, you will see gains.

To ensure this, lift weights and do HIIT cardio. Stress the body with intensive, heavy sessions (relative to your current fitness levels) to ward off cortisol and promote new mass. Be sure to keep your appetite steady by eating a healthy diet of fats and proteins, as this will level out your leptin and metabolism. Cut your carbs to reduce insulin sensitivity and drive away excess fat. Now that you’ve seen the light behind hormones, your workouts will produce lightning fast muscle gains!

Fitplan helps you achieve your fitness goals by sharing the exact training methods of the world’s top athletes.

Best of all? It’s free to get started!

Exclusive Bonus: Download 6 Superfoods Guaranteed to Boost Growth Hormone Levels to know the healthy foods that can tone and definition in no time!

Related Posts