Models of muscle contraction and energetics

How skeletal muscles manage to regulate the pathways of ATP synthesis during large-scale changes in work rate while maintaining metabolic homeostasis remains unknown. The classic model of metabolic regulation during muscle contraction states that accelerating ATP utilization leads to increasing concentrations of ADP and Pi, which serve as substrates for oxidative phosphorylation and thus accelerate ATP synthesis. An alternative model states that both the ATP demand and ATP-supply pathways are simultaneously activated. Here, we review experimental and computational models of muscle contraction and energetics at various organizational levels and compare them with respect to their pros and cons in facilitating the understanding of the regulation of energy metabolism during exercise in the intact organism.

Section editor:Paolo Vicini – Pfizer Global Research and Development, Department of Pharmacokinetics, Dynamics and Metabolism, San Diego, CA, USA