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Are your hormones affecting your muscle gain?

Struggling to gain muscle? Could your hormones be to blame? Find out more in this blog.

It's easy to take our hormones for granted until they stop performing as they should. A healthy hormone system enables us to stay in shape and conduct our daily activities, but it’s even more important to those trying to gain muscle. It can be frustrating to dedicate a lot of time and effort to your physique and not see the desired results, yet hormones are rarely thought to be the culprit. With diet and training taking centre stage, hormones become an overlooked factor in muscle growth. Here we take a look at the five key hormones that power our muscles and how you can adapt your training techniques for a better outcome.

How do hormones affect muscle growth?

Let’s start with the basics. Before we suggest any changes to your workout routine or diet, it’s helpful to explain why you should bother considering hormones at all. Hormones are vital in regulating our metabolism – the reaction that governs our energy and processes our food intake. During and after a workout, your body is flooded by different hormones which are either anabolic (those that use energy) or catabolic (those that release energy). Only the muscles stimulated during this exercise are subject to the effects of these hormones [1]. For muscle growth, you need a higher amount of anabolic hormones than catabolic. These hormones include:

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

Anabolism enables our muscles to grow because the process involves simple molecules forming together into larger, more complex ones and retaining energy for repairs. Catabolic hormones, such as cortisol, inhibit muscle growth as the process breaks down molecules and releases energy, for example, food digestion. If there is a higher imbalance of catabolic hormones, you will begin to lose muscle mass. Any hormonal disruptions, for example, those caused by a thyroid condition, will affect these processes and your overall metabolism [2]. If you’re concerned about a hormone imbalance, or curious what your baseline levels are, Medichecks’ provides a range of at-home blood tests that can give you peace of mind. There are many things you can do to ensure a healthy hormone balance, but before we discuss those, let’s learn more about the specific hormones involved.

Key hormones

When creating a training plan, it’s important to bear in mind that hormones affect muscle growth and strength differently. For bodybuilding, your anabolic hormones play a critical role by stimulating muscle growth. Other hormones, such as cortisol, epinephrine, and glucagon, increase the availability of glucose (your body’s source of fuel) and aid strength training.


This male hormone is primarily produced by the testicles, and by the ovaries in women, albeit in lower quantities. Testosterone regulates muscle mass, strength, fat distribution, libido, and bone mass [3]; making it one of the most important hormones for bodybuilding. Classed as an anabolic hormone, testosterone increases neurotransmitters in the nervous system to enhance your muscle’s size. Using testosterone supplements is rather popular amongst bodybuilders but has been banned in sports competitions as it comes with many potential health risks.

Here are some natural techniques that you can use to boost your testosterone levels:

  • Keep workouts shorter than 1 hour.
  • Do multiple sets of each exercise.
  • Include compound exercises
  • Make sure your rest intervals last less than 1 minute.
  • Keep resistance training to an 80-90% maximum.
  • Workout your legs - this stimulates your largest muscles and therefore produces more testosterone [1].

You can easily monitor your testosterone levels with our at-home Male HormoneBlood Test. This test provides you with a thorough hormone MOT, so you can see if your hormone range is healthy for your age, or whether an imbalance could be affecting your muscle gain.

Growth hormone (GH)

Growth hormone supports the development of skeletal muscle tissue, body strength, and eliminating body fat. GH production declines with age, which means the less GH you produce, the more body fat you will accumulate [4]. Your body releases GH during its REM cycles of sleep and uses this time to repair any damaged muscle cells. Improving your quality of sleep will, in turn, help your workout efforts. Exercise also releases growth hormone, particularly compound movements that use multiple joints, for example, squats or bench presses. The more muscle fibres you are using, the more GH your body will create. You should also try to shorten your workouts (approximately 30-40 minutes), as the quicker, more intense duration produces a higher hormone output.


Insulin is responsible for storing the product of food breakdowns in the muscles and liver. As another anabolic hormone, it moves amino acids into your muscle cells to help repair tissue. Insulin can have positive impacts on your muscles but could also become a burden if you have excess body fat. The production of insulin is heavily influenced by diet and exercise, so it can be something that you control. However, you may not know that training can increase your body’s sensitivity to insulin, which is why it’s always so hard to lose the last bit of fat. Once you’ve lost some weight, your body shifts into survival mode and tries to protect the remaining fat and muscle it needs to function. To combat this, try eating healthy fats that insulin is less sensitive to, for example, fish, nuts, coconut oil etc.

Insulin-like Growth Factors (IGFs)

This hormone is produced in the liver in response to the growth hormones, so if GH levels rise, as do IGFs. As the name suggests, IGFs stimulate muscle growth as well as increase lean body mass, helping you burn fat, increasing your physical endurance and accelerating your recovery time [5]. Your IGF levels peak during puberty and gradually decrease with age. If you’re looking for the best natural method of increasing your IGF levels, exercise is the answer. We recommend either High-Intensity Interval Training (HIIT) or resistance training. Improving your sleep quality and avoiding alcohol are also known to benefit your IGF levels.


Cortisol is a catabolic hormone that is triggered by physical and emotional stress. It breaks down your muscles when your blood sugar is low, so those of you that enjoy endurance sports may have experienced its effects. By breaking down the tissue, cortisol can prevent your muscle gain, making it clear why minimising your cortisol levels is beneficial for bodybuilders. But how can you minimise cortisol when training? The answer is often simple - try to avoid lengthy cardio sessions. Unfortunately, exercises that cause GH to release, such as using heavy weights and large muscle groups, also stimulate high levels of cortisol. But when they are completed in short-term durations, the cortisol can be helpful as muscles need to be broken down slightly in order to grow.

How else can I enhance my performance?

It’s clear to see why you should vary your exercises at the gym. Different routines will stimulate different hormones and help to achieve your growth goals. To summarise, you should try to minimise your catabolic hormone release by keeping the duration of your workouts shorter and making sure you are not excessively stressing your muscles. You should also aim to stimulate your anabolic hormones for muscle growth; this is best done by weight training and HIIT cardio workouts. But is there anything else you could be doing to enhance your performance?

Diet and nutrition

We’ve all heard the saying that fitness is 80% diet and 20% exercise, and yet we often fail to eat the right foods. It is important to consider not only what you are eating, but also when. Certain foods before, during and after your workout could make a big difference in your progress. We recommend:

  • Eating fewer carbs can increase your growth hormone.
  • Eating carbs before or during your workout minimise cortisol levels.
  • Fasting – when done safely, can increase GH levels.
  • Eating protein after a workout to keep your testosterone levels high.
  • Keeping your carb-protein ratio at approximately 3:1 after a heavy workout.
  • Sipping a sports drink throughout your workout to keep your glucose levels up.
  • Avoiding supplements as they can have adverse side effects.
  • Keeping all nutrition balanced. Try to avoid diets that are too low or too high in specific food groups.

Other tips

Aside from diet and training movements, other less obvious factors could influence your hormone production and progress. Here are some extra tips to consider:

  • When doing endurance training, try to rest for 3-5 minutes in between sets. This stimulates testosterone production and helps you to perform better once your body has had ample time to recover.
  • Complete any aerobic and anaerobic exercises on separate days, they each have such distinct effects on the body; it is counterintuitive to do them in close proximity and risk inflammation or high cortisol levels.
  • You should always try to ensure good quality sleep as not only would you feel well-rested and ready to combat any workout, but your GH levels are stimulated during deep sleep.
  • Do any weight training in the evenings rather than early morning. Your cortisol levels tend to be at their highest soon after you have woken up.

A health check could help highlight any issues so you can take action before they hinder your progress. Our Male Hormone Blood Test explores key blood markers which allow you to determine the cause of the problem and adjust any imbalances. With Medichecks' online health portal, it's easy to monitor your levels over time and take control of your health. There is never a straightforward answer to muscle growth, but a holistic approach will ensure you have the best chances in moving forward and achieving your goals.


[1] Speck, C. (2019) Master Your Hormones to Maximise Muscle Growth. [online] Fit Plan. Available at: [Accessed 08/06/20].

[2] Marcin, A. (2019) Catabolism vs Anabolism: What's the Difference? [online] Healthline. Available at: [Accessed 08/06/20].

[3] Wein, H. (2013) Understanding How Testosterone Affects Men. [online] National Institutes of Health. Available at:,estradiol%2C%20a%20form%20of%20estrogen. [Accessed 08/06/20].

[4] Rogers, P. (2020) How to Stimulate Hormones for Bodybuilding. [online] Very Well Fit. Available at: [Accessed: 03/06/20].

[5] Eriksson, A. (2020) Growth And Longevity: The Enigma And Potential Of IGF-1. [online] Breaking Muscle. Available at:,and%20accelerates%20recovery%20from%20injuries. [Accessed 08/06/20].