Part 1 – Anatomy and Physiology of Muscles & Growth Factors
The goal of the next articles is to acquaint our readers with the science of muscle growth and repair. This will be done in two parts.
- The first article will familiarize you with the anatomy and physiology of muscles and how they grow as well as the effects that various hormones and growth factors have on muscle growth.
- The next article will delve into the nutritional aspects of muscle growth. Certain amino acids play more of a part in muscle growth and repair than others and you will learn which they are. We will also describe additional nutritional entities that have the ability to make a difference in how you build muscle or recuperate from an injury. Milk proteins such as casein and whey are two of the outstanding protein sources of these substances that enhance the process of growth and repair of muscle.
Anatomy and Physiology of Muscles
Muscle growth is absolutely related to resistive exercise such as lifting weights. Public and private gyms are more popular than ever. The reason is that significant numbers of the population have realized the physical and emotional benefits of regular exercise in addition to muscle growth.
The Centers for Disease Control and Prevention recommends that all adults get at least 30 minutes of moderate exercise five days a week. Although pumping iron is critical for muscle growth, studies have shown that even a consistent commitment to walking is associated with a decreased risk of mortality and decreased lifetime medical expenditures (1).
In addition to building skeletal muscle, the benefits of regular exercise include improved cardiovascular health, an improved cholesterol profile, decreased chance of developing diabetes, weight control, decreased incidence of some cancers, and a better mental outlook on life which translates into an improved ability to deal with adversity.
The human body has three types of muscle tissue-skeletal, cardiac, and smooth. They differ from one another in their microscopic anatomy, location, and control by the nervous and endocrine (hormonal) systems. Cardiac muscle tissue forms most of the heart. Smooth muscle tissue is located for the most part in the abdomen around and in most of the organs. This article will deal with skeletal muscle which is quite different in that it can be made to relax and contract voluntarily and is therefore under our control (2). It is known as voluntary as opposed to involuntary muscle.
Skeletal muscle is so named because it is attached primarily to bones and therefore contraction of various muscle groups enables us to move about voluntarily. Muscle cells are composed of tubular units called myofibrils. Myofibrils are composed of repeating sections called sarcomeres, which appear under the microscope as dark and light bands. Sarcomeres are composed of long, fibrous proteins that slide past each other when the muscles contract and relax.
The two important protein substances that compose muscle tissue are myosin which forms the thicker filaments, and actin which forms the thin filaments. A good supply of amino acids via the protein we consume is required to form both actin and myosin.
Contractility is the ability of the muscle to shorten and contract and thus cause movement in response to nerve impulses. Amyotrophic lateral sclerosis (ALS), also called Lou Gehrig’s disease or classical motor neuron disease, is just one of many diseases that disrupts nerve signals to the voluntary muscles and renders them unable to contract at will.
How Does Lifting Heavy Weight Result In Muscle Growth
What Are the Effects of Hormones and Growth Factors?
These are the basic factors for muscle growth and repair. Be patient, stay active, work hard, but don’t overdo it and hurt yourself. In the next segment we will describe how consuming the appropriate nutrients can also be a significant factor in achieving your goal, whether it be building more muscle, recovering from an injury, or simply enjoying life more by being fit.