Desarrollo Muscular

Abstract: Throughout this extended essay, we will look at some of the factors that affect skeletal muscle development which mainly refers to strengthening and preservation. The main causes affecting muscle development according to this investigation are ageing, the lack of necessary proteins and hormones and finally but not least important the lack of movement of the muscles. As the essaycontinues, you will learn much about skeletal muscle composition, how it works (different type of contractions), how it is trained and muscle response to training depending on age, type of contraction, and availability of the nutrients in the muscle. This essay also examines an proposes the usage of supplementation (hormonal and non hormonal) to preserve and help the muscle to develop more accuratelyincluding within this supplements creatine and testosterone and how they can increase muscle development when used correctly and with the right dosage. Finally, the essay talks about a muscle degenerative disease called sarcopenia and proposes a cure to this disease which in case of functioning would stop and prevent muscle deterioration not only to people predisposed genetically to getting thisdisease, but to athletes and other people who would like to keep their muscles functional for their whole life.

Topic: What factors affect the development (strengthening and preservation) of the muscular system?

Problem: Currently, experimental evidence has shown that the musculoskeletal system begins to deteriorate after thirty years of age in man (male) causing loss of strength, speed,elasticity, etc. This is one reason why most male athletes retire at around that age. Causing the following question: could there be any way you could reduce, reverse or stop the process of muscle deterioration?
In order to understand this topic adequately first we have to know what skeletal muscle is, how is that it functions (different types of contractions) and how it is divided (type one and typetwo fibers). The term muscle refers to multiple bundles of muscle fibers held together by connective tissue. “Skeletal muscle is a form of striated muscle tissue existing under control of the somatic nervous system. It is one of three major muscle types, the others being cardiac and smooth muscle. As its name suggests, skeletal muscle is linked to bone by bundles of collagen fibers known astendons. Skeletal muscle is made up of individual components known as muscle fibers, these myofibers are long, cylindrical, multinucleated cells composed of actin and myosin myofibrils repeated as a sarcomere, the basic functional unit of the cell and responsible for skeletal muscle's striated appearance and forming the basic machinery necessary for muscle contraction” (1).
“Individual muscle fibersare formed during development from the fusion of several undifferentiated immature cells known as myoblasts into long, cylindrical, multi-nucleated cells. Differentiation into this state is primarily completed before birth with the cells continuing to grow in size thereafter. Skeletal muscle exhibits a distinctive banding pattern when viewed under the microscope due to the arrangement ofcytoskeletal elements in the cytoplasm of the muscle fibers” (2). The principal cytoplasmic proteins are myosin and actin (also known as "thick" and "thin" filaments, respectively) which are arranged in a repeating unit called a sarcomere. The interaction of myosin and actin is responsible for muscle contraction.
"Skeletal muscle can thus be broken down into two broad categories: Type I and Type II. Type Ifibers appear red due to the presence of the oxygen binding protein myoglobin. These fibers are suited for endurance and are slow to fatigue because they use oxidative metabolism to generate ATP. Type II fibers are white due to the absence of myoglobin and a reliance on glycolytic enzymes. These fibers are efficient for short bursts of speed and power and use both oxidative metabolism and...