Introduction
Sarcopenia can be defined as the age-related loss of muscle mass, strength and function (Waters, Baumgartner & Garry 2000; Vandervoort & Symons 2001). Although there is no specific level of lean body mass or muscle mass at which one can say sarcopenia is present (Roubenoff 2001), any loss of muscle mass is of importance because there is a strong relationship between muscle mass and strength (Roth, Ferrell & Hurley 2000). Sarcopenia appears to begin in the fourth decade of life and accelerates after the age of approximately 75 years (Waters, Baumgartner & Garry 2000). With aging and inactivity, the most atrophy is seen in the fast twitch (FT) fibers which are recruited during high-intensity, anaerobic movements. Although sarcopenia is mostly seen in physically inactive individuals, it is also evident in individuals who remain physically active throughout their lives. This finding suggests that physical inactivity is not the only contributing factor to sarcopenia. Current research is finding that the development of sarcopenia is a multifactorial process. Many factors, including physical inactivity, motor-unit remodeling, decreased hormone levels, and decreased protein synthesis, may all contribute to sarcopenia. Fortunately, sarcopenia is partly reversible with appropriate exercise interventions. This article will focus on the current perspectives of sarcopenia and conclude with the importance of resistance training in preventing it.
Motor Unit Remodeling
Age
As the trials progressed, the strength of the muscles decreased as well because of the experienced muscle fatigue due to the lactate threshold. In
This component can also be linked in with the third component of muscular endurance, with age this factor is often limited by lack of muscular strength due to shorter bouts of exercise being performed.
“Today, it is common knowledge that exercise is the equivalent of a drug that prevents and treats cardiovascular disease (1).” Therefore, it is essential that individuals strive to exercise for at least 30 minutes a day, 3-5 times a week. In today’s society, the end goal of exercise is often physical attractiveness rather than bodily health. The media is oversaturated with unrealistic ideals that push people to work towards dangerously low body weights. These ideals, however can only offer temporary satisfaction. The process of aging occurs in all individuals, regardless of fitness level. Physical attractiveness
Description of subjects and methods: This particular study pertaining to the effect of pre-exercise creatine ingestion on muscle performance in healthy aging males was a double blind, cross-over design with repeated measures in which participants of the study ingested creatine, and a placebo, depending on their randomized assignment to a group separated by seven days, and three hours prior to performing chest press and leg press repetitions until muscle fatigue occurred. After ingesting either the creatine or placebo, the participants were instructed to refrain from caffeine, alcohol, food, drinks, and physical activity but water was permitted to the participant's amount of choosing. Seven days were spread between testing to guarantee that adequate muscle recovery between sessions was
The disease associated with aging of the muscles is called “Sarcopenia.” What this is according to, “Tae Nyun Kim and Kyung Mook,” Sarcopenia causes “Reductions in muscle mass and physical activity levels decrease total energy expenditures, which results in the accumulation of fat mass, especially visceral fat.” Which is the reduction of the muscle fibers.
Simply put, if muscle protein synthesis is not taking place, the muscles are breaking down.
Several cross-sectional, observational studies have related sarcopenia to decline of functional status, such as mobility performance, self-reported functional limitations, and disability, it is well established that the aging process itself is associated with numerous changes in the human body. One of the most significant age-related anatomical changes is that which happens to the skeletal muscle mass (Visser and Schaap, 2011).
Sarcopenia is the progressive loss of skeletal muscle mass and function with age. It often is a result of or leads to decrease in physical activity which leads to functional impairement or disability and increases vulnerability towards other chronic ailments such as cardiovascular disease, insulin resistance, type 2 diabetes etc (Roubenoff & Hughes 2000). With age there is a decline in mitochondrial biogenesis as well as reduction in the ability to promote muscle protein synthesis which has substantial impact on the age-associated loss of muscle mass and strength, both of which are the two most recognized risk phenotypes associated with sarcopenia. Previous work has reported enormous inter-individual variability in these phenotypes arising
Spinal Muscular Atrophy (SMA) is defined as a genetic disease affecting the part of the nervous system that controls voluntary muscles. Atrophy means wasting away, hence exactly what the disease is doing. SMA is characterized by loss of motor neurons in the ventral horn of the spinal cord, leading to weakness and muscle atrophy (Monir Shababi, 2013). The motor nerves receive impulses that come from the brain to the spinal cord, and then transmit the impulses back to the muscles, so when the signals do not work, this is what causes SMA. The loss of these motor neurons leads to your muscles “wasting away.” These muscles are necessary in order for us to
Muscular strength and endurance can be gained through weight and resistance training. Doing less repetitions with more weight will help you increase your muscular strength. Doing more repetitions with lighter weights will help you build up muscular endurance. As I grow older I learned that I need regular aerobic exercise, such as walking, swimming, or running, to strengthen my heart and lungs and tone my body, however I didn’t realize that I needed weight training. It can slow, and even reverse, muscle mass, bone density, and strength loss as I get older.
Mobility is essential for general independence as well as ensuring good health and quality of life (QoL) (Michelle, Jim, Jennifer, Sjaanie, & Judith, 2006). In old age, muscle weakness due to sarcopenia is responsible for the occurrences of frailty and important disability (Fried, et al., 2001). Especially in institutionalised elderly persons, muscle strength can deteriorate to a point where it becomes critical for independence of transfers and walking. There is strong evidence that in healthy older persons major gains in muscle strength can be obtained by resistance exercises (Latham, Bennett, Stretton, & Anderson, 2004). The ability to walk for a short distance and the grip strength are quick and inexpensive measure of physical function, and are important components of quality of life, since it reflects the capacity to undertake day-today activities. The six-minute walk distance test (6MWD) was developed by (Balke, 1963), to evaluate functional capacity like cardiovascular or pulmonary disease.
The European Working Group on Sarcopenia in Older People (EWGSOP) developed a clinical definition and consensus diagnostic criteria for age-related sarcopenia (Cruz-Jentoft et al., 2010).
These can range from lifting very heavy weights, to intricate tasks such as playing a piano, to pumping blood non-stop for a lifetime. To accommodate such wide variation, muscles have high plasticity and can adapt to changing activity levels and environments. For example, endurance exercise increases the oxidative capacity and makes muscle more fatigue resistant while disuse leads to muscle atrophy [1]. The pathways underlying these changes and muscle plasticity are therefore of great interest.
Aging of the population is a worldwide phenomenon that is accompanied by a series of modifications to several physiological parameters, such as a progressive increase in fat mass and a decrease in lean body mass. However, these alterations are not linear and must be constantly monitored.In elderly individuals, changes in body composition result in the prevalence of overweight and obesity combined with a loss of muscle mass and strength; this has recently been defined as sarcopenic obesity.Sarcopenic obesity is associated with functional limitations and increased mortality.The aim of the present study was to investigate the prevalence of sarcopenic obesity and its association with obesity and sarcopenia in elderly Brazilian women. Two hundred
Muscle fatigue is defined as a decrease in the maximum force generating capacity of a muscle (3). Muscle force and fatigability are correlated to muscle mass, muscle fiber type, and motor unit recruitment. Muscle fibers consume stored energy and generate force by contracting. If a muscle depletes its fuel supply faster than they can be replenished by metabolism, then fatigue occurs. The purpose of this study was to determine the time to fatigue to 50% of maximum clench force for both dominant and non-dominant arms, and then determine differences between male and female. Recent literature has suggested that there are sex differences in muscle fatigability, however the physiological mechanisms are not entirely understood. In general, men have