Skeletal muscle has long been viewed as an organ primarily responsible for locomotion, characterized by seemingly simple anatomical and biochemical features. The growing recognition that exercise is medicine—and that physical activity plays a vital role in health and disease prevention—has greatly increased interest in, and demand for, a deeper understanding of skeletal muscle. This book describes the fundamental biological features of skeletal muscle, including its development, gross and fine structure, contractile mechanism, bioenergetics, metabolic regulation, gene regulation, redox homeostasis, and cell signaling. It provides an up to date, chapter-by-chapter overview of knowledge derived from both historical and contemporary research, offering sufficient detail on each aspect. In-depth scientific foundations at the genetic and molecular levels are presented to enable a comprehensive understanding of how this organ supports not only locomotion but also whole-body homeostasis. A distinctive feature of the book is its emphasis on signal transduction arising from various physiological demands, highlighting hormones, cytokines, transcription factors, and reactive oxygen and nitrogen species as key messengers. This field—known as redox biology or redox signaling—has expanded rapidly over the past two decades, driven by advancements in information technology and biotechnology.
