By Dr. Dimitar Marinov

medical reviewed by Best HGH Doctors and Clinics dedicated team.

Evidence basedThis article is reviewed by medical professionals for the relevancy and accuracy of the content. Every article is evidence-based and contains references to peer-reviewed studies and academic research.

If you are losing size and definition in your muscles, growth hormone deficiency (GHD) might be the reason. Patients with GHD often experience muscle loss, reduced physical strength, and endurance. Losing muscle mass is the result of an imbalance between muscle protein synthesis and degradation.

Decrease in muscle mass and strength

Suddenly, you might find it impossible to do the same physical activities as you used to.

Muscle loss can also affect your overall well-being. It is associated with multiple health problems such as slower recovery from illness, prolonged wound healing, sluggish metabolism, and poorer quality of life. Furthermore, you are at higher risk of insulin resistance and type 2 diabetes.

The first signs of muscle loss in patients with GHD include changes in body composition and appearance. Your weight will not decrease and might even increase because muscle loss is accompanied by an accumulation of abdominal fat.
Muscle loss can be also caused by:

  • aging (sarcopenia)
  • immobilization
  • malnutrition
  • infections
  • cancer
  • chronic pulmonary, heart, gastroenterological, or kidney conditions
  • nervous system and muscle diseases

The Role of GH in the Regulation of Muscle Mass

HGH is a key regulator of muscle growth and hypertrophy via its mediator – insulin-like growth hormone-1 (IGF-1). HGH stimulates IGF-1 synthesis in almost all tissues where it has a local anabolic effect. Besides, the growth hormone stimulates its production in the liver and then IGF-1 is released in the blood circulation.

The production of IGF-1 inside the muscle is a crucial factor for muscle growth. HGH and IGF-1 are not only capable of stimulating muscle hypertrophy, but also protect the human body against age‐related loss of muscle mass and strength.

Scientific evidence shows that IGF-1 has an impact on both muscle protein synthesis and protein breakdown. In fact, animal studies suggest that the hormone has stronger muscle-sparing effects rather than muscle-building ones. Because of these findings, it is widely accepted that HGH has a key role in preventing muscle wasting.

How to Prevent Muscle and Strength Loss due to GHD

GHD causes a decline in IGF-1 levels. The plummeting anabolic effects of the hormone lead to an increased rate of protein breakdown and muscle loss inside your organism.

HGH therapy can prevent muscle loss by increasing serum levels of IGF-1 as well as stimulating IGF-1 production inside the muscle tissue

HGH injections can also increase protein synthesis and muscle mass in cases of sarcopenia (muscle loss caused by aging). According to animal trials, recombinant HGH is effective in attenuating age-related muscle wasting by two main mechanisms:

  • increasing IGF-1 levels and muscle protein synthesis
  • reducing age-associated oxidative damage and stimulating antioxidant enzymes in the skeletal muscle

These effects are due to the rapid increase in IGF-1 levels, which peak during the first month of treatment. The long-term effects of HGH therapy include maintaining normal IGF-1 levels and attenuating muscle wasting.

If GHD is left untreated, it can lead to significant muscle loss that will cause physical disability and lack of support for your bones.

Discover more about GHD and the increased risk of fractures and osteoporosis


GH deficiency speeds up the bone loss that occurs with age and makes your skeleton fragile. Also, bone fractures in the hip, wrist, or spine can occur even if there was no serious trauma

Find out more