DANIEL R. MOORE
Faculty of Kinesiology and Physical Education, University of Toronto, 55 Harbord St., M5S 2W6, Toronto, Ontario, Canada

Abstract

The optimal stimulation of muscle protein synthesis (MPS) is essential to facilitate muscle remodelling and recovery after all forms of exercise. Dietary protein is the key macronutrient that enhances post-exercise MPS with a moderate 20g dose eliciting maximal rates. Rapidly digested, leucine-enriched proteins such as whey appear to be especially effective in the stimulation of MPS. Ingestion of protein immediately after exercise is necessary to maximize post-exercise MPS, although repeated ingestion of moderate doses at regular intervals throughout the day as well as immediately before sleep can sustain daily rates of MPS to further enhance muscle remodelling. Therefore, individuals aiming to enhance their recovery from, and ultimately adaptation to, exercise should consider dietary protein as a vital component of their recovery nutrition.

INTRODUCTION

Skeletal muscle is an incredibly plastic tissue with the ability to adapt to a wide-variety of exercise stimuli to alter its phenotype towards the specific demands of a physical task. For example, resistance exercise (e.g. weight lifting) predominantly simulates the synthesis of contractile myofibrillar proteins to increase muscle size and/or strength whereas endurance exercise predominantly stimulates the synthesis of the energy-producing mitochondrial proteins to enhance aerobic energy production (1). However, this classic ‘strength vs. endurance’ exercise paradigm is a simplistic view of most training programs given that these exercise stimuli more accurately fall along a continuum, rather than being mutually exclusive, with training programs often featuring components of each. Nevertheless, the common feature of any exercise stimulus that elicits a training response overtime is the enhancement of skeletal muscle remodelling that occurs in the hours to days after each training session (2).

Skeletal muscle is remodelled through the continuous and simultaneous processes of protein synthesis (MPS) and protein breakdown (MPB), col ...