Have you ever thought “Why aren’t I gaining muscle mass or size?” or wondered why you may not be seeing the desired results from the training effort you are putting in? As a Dietitian, I see this a lot and there is usually an underlying reason hypertrophy is not occurring at the pace you would like, and involves a bit of investigation.

Firstly, it’s important to understand the physiology of muscle hypertrophy (growth). After you workout, your body starts to repair or replace the damaged muscle fibres through a cellular process where it fuses muscle fibres together to form new strands of muscle protein called myofibrils. These repaired myofibrils increase in thickness, size and number to create muscle hypertrophy. Muscle growth only occurs whenever the rate of muscle protein synthesis is greater than the rate of muscle protein breakdown. This adaption, surprisingly, does not happen while you actually lift the weights. Instead, it occurs while you rest.

Muscle growth is further influenced by the type of exercise performed, nutritional intake, and hormonal status. There are some obvious reasons why you are not building lean muscle that are repeatedly addressed in the media such as not eating enough protein, not eating the right type of protein, poor workout routine, improper form, doing too much cardio etc., but I am going to focus on some of the reasons you may have overlooked or haven’t paid attention to, or didn’t even know they play a role.

  1. Not eating enough calories– under-eating or calorie restriction is one of the most obvious and common problems associated with the inability to put on size. While you are able to lose weight with a caloric deficit, the losses are most likely to come from both muscle and fat. The biggest problem most people have is that they want to lose fat mass as well as put on lean muscle at the same time. As a result, they will experiment with calorie deficits and surpluses, which compromises their nutritional intake and they end up with mixed results.Your body requires a certain number of calories to maintain your current weight. This figure is known as your basal metabolic rate (BMR), and varies from person to person depending on your weight, muscle mass, activity level, age and gender. If your calorie consumption is lower than your calculated BMR (calorie deficit), you will lose weight. If your daily calorie intake is higher than your BMR (calorie surplus), you will gain weight. To optimise your muscle growth, you need to be in calorie surplus.
  2. You are over-training– This is not to be confused with the overload principle to build muscle. We all know that to build muscle, it’s beneficial to lift heavy. Exercise and weight training cause injury to skeletal muscle fibres. As a result, the body releases various signaling molecules to start the repair process and reduce inflammation. While this response is necessary for muscular development, it can lead to over-training syndrome if there is not sufficient recovery time given to the body. This is generally seen in people who train more than once per day and don’t implement any rest days through the week. Excessive inflammation from over-training can result in muscle fatigue, loss in muscle protein, loss of muscle mass, and reduced muscle function. It can also compromise your body’s immune function, which increases your risk of illness, disease and the common cold and flu.
  3. Hormone imbalance– Hormone production, regulation and metabolism is largely responsible for muscle growth and repair. The major hormones that modulate muscle growth include: growth hormone (GH), testosterone, Insulin Growth Factor (IGF-1), cortisol, parathyroid hormone and beta-endorphin. IGF-1 and testosterone are the two most vital mechanisms that promote muscle growth.Testosterone is the main hormone that most people think of when it comes to lifting weights. Testosterone is responsible for increasing protein synthesis, inhibiting protein breakdown, activation of satellite cells, and stimulation of other anabolic hormones. Testosterone can also stimulate growth hormone responses, which can help to activate tissue growth.

    If you have a hormone imbalance e.g. prolonged elevated cortisol, testosterone (androgen) deficiency or underactive active thyroid, it will inhibit your body’s ability to grow muscle appropriately. If you feel like you are working hard in the gym and you have a good, calorie controlled diet, and you are not seeing the results you want, you may want to consider investigating your hormone levels. Check with your medical or health professional which method of testing (blood, saliva or urine) is right for you as some methods are more accurate than others when it comes to hormones.

  1. Lack of sleep– There are many negative effects associated with sleep deprivation, and compromising your body’s ability to repair damaged muscle tissue and grow muscle is one of them. Poor quality or a lack of sleep elevates your body’s cortisol level. Cortisol is known as our stress hormone and is a catabolic hormone, meaning that if there are consistent elevated levels of cortisol it will eventually break down muscle tissue. Additionally, growth hormone production usually reaches its daily maximum during the first half of the normal sleep period/cycle. Therefore, sleep deprivation decreases growth hormone levels, which further compromises your body’s ability to build muscle during the rest and repair phase.
  2. Poor gut health– Our digestive system is the epicentre of good health and is responsible for the majority of our immunity. The gastrointestinal lining is loaded with villi, responsible for nutrient absorption, and neurons that release neurotransmitters and messages to the brain, which in turn triggers specific hormone production.

It makes sense that since 99% of your nutrient assimilation occurs through food transporting through your digestive system, if your digestive system is not functioning optimally, then your nutrient uptake is not optimal either. That means that any vitamins, minerals, proteins, carbohydrates, fatty acids, or supplements you ingest are not going to be used to their fullest potential for energy, recovery, muscle growth and repair. People with gastrointestinal disorders or conditions such as irritable bowel syndrome (IBS), coeliac disease, Crohn’s disease, ulcerative colitis, reflux, food allergy or intolerance and increased gastrointestinal permeability, are at further risk of their body inappropriately absorbing nutrients.

If you experience regular symptoms such as gas, bloating, abdominal pain or cramps, diarrhoea, constipation, reflux, belching, nausea or vomiting, it is a good idea you investigate the cause with your doctor.

By avoiding these mistakes or investigating any health concerns, you are more likely to facilitate muscle growth, repair and recovery in a shorter time frame. These are not the only exist out there so persevere and continue to seek advice from health and fitness professionals about new training and dietary strategies for maximising your results.