Among these keywords, “elderly men,” “young,” “age,” “men,” “old rat” are subjects of exercise rehabilitation studies for sarcopenia, “growth factors,” “protein synthesis,” “messenger rna,” “hypertrophy,” “growth hormone,” “satellite cell,” “necrosis factor alpha,” “necrosis factor alpha,” “igf i,” “myosin heavy chain,” “caloric restriction,” “essential amino acid” are the key research directions. The gene discussed is IGF1; the disease is sarcopenia.