ABSTRACT
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305 Definition and Prevalence of Sarcopenia . . . . . . . . . . . . . . . . . . . . . . . . . . . 305 Clinical Significance of Sarcopenia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 Potential Mechanisms of Sarcopenia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308 Exercise can Attenuate Sarcopenia and Its Effects . . . . . . . . . . . . . . . . . . . . 310 Dietary Protein and Amino Acids Play a Role in Preventing Sarcopenia . . . 311 Additional Dietary Supplement Strategies in Treating Sarcopenia . . . . . . . . 316 Growth Hormone and Muscle Mass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317 Insulin-Like Growth Hormone I and Muscle Mass . . . . . . . . . . . . . . . . . . . 318 Testosterone and Muscle Mass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 Oxandrolone and Muscle Mass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 Estrogen and Muscle Mass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 DHEA and Muscle Mass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 Summary and Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Skeletal muscle is vitally important for posture, balance, and locomotion and acts as a major metabolic organ. Loss of muscle mass and function with age puts older people at risk for falls, obesity, diabetes, and dependent living. Muscle loss may be a marker of aging itself. This chapter considers the mechanisms, consequences, and treatments for age-related decline in skeletal muscle size and function, also referred to as sarcopenia.
