Aerobic muscle function during steady swimming in fish

# 2002 Blackwell Science Ltd 63 Abstract Axial swimming in ¢sh varies across a range of body forms and swimming modes. Swimmingbyeels, tunas,mackerels, scup, rainbow trout and bass span this range from high curvature anguilliform swimmers to rigid body thunniform swimmers. Recent work on these and other species has elucidated an impressive array of solutions to the problem of how to use the red (aerobic, slow-twitch) muscle to power steady or sustained swimming.This reviewwill use a comparative approach to understand the generalities of aerobic muscle function during steady swimming in ¢sh and determine possible rules for the relationships between muscle contractile kinetics, in vivomuscle activity and power output during swimming. Beyond an exploration of the diversity in muscle activity and swimming kinematics, I suggest that analysis of the molecular basis for longitudinal variations in muscle function is needed to complement morphologicalandphysiological researchon¢shmuscle.Thiswill permit bothageneralunderstanding of the integrative function of the ¢sh myotome and, perhaps, predictive tools for muscle activityand swimming performance in ¢sh. Correspondence: David J Coughlin, Department of Biology,Widener University, Chester, PA19013, USA Tel.:þ1610 499 4025 Fax:þ1610 499 4496 E-mail: coughlin@ pop1.science. widener.edu