Initiation of movement, whether in the form of voluntary action by skeletal muscle, or the contraction of cardiac or smooth muscle, is the clearest observable physiological manifestation of animal life. It inevitably involves activation of contractile tissue initiated or modulated by altered activity in its nerve supply. An appreciation of the function of nerve and muscle, and of the relationships between them is thus fundamental to our understanding of the function of the human body.

This book provides an introductory account of this important aspect of physiology, in a form suitable for students taking university courses in physiology, cell biology or medicine. It seeks to give a straightforward account of the fundamentals in this area, whilst including some of the experimental evidence upon which our conclusions are based.

This fourth edition includes new material reflecting the exciting discoveries concerning the ion channels involved in electrical activity, the activation of skeletal muscle and the function of cardiac and smooth muscle, reflecting important new developments made in these rapidly growing fields. We are grateful for expert advice and specialist comments from Drs. James Fraser, Ian Sabir and Juliet Usher-Smith, Physiological Laboratory, Cambridge, and Thomas Pedersen, Department of Physiology, University of Aarhus, and continue to benefit from the insight and wisdom left us by the late David Aidley, in these revisions.