Abstract

Scientific interest in the topic of interval training has grown rapidly over the past two decades, in part because interval training is a potent exercise stimulus that elicits cellular adaptations traditionally associated with moderate-intensity continuous training (i.e., classic endurance training). Many varieties of interval training have been examined within the literature, and this chapter begins with a brief overview of interval exercise definitions, nomenclature, and prescription. At the centre of this chapter is a discussion of the skeletal muscle cellular adaptations resulting from interval training. Here, the chapter focuses on activation of the mitochondrial biogenesis pathway, improvements in mitochondrial content, changes in the abundance of proteins related to carbohydrate and fat transport, storage and oxidation, and skeletal muscle capillarization. Comparisons of skeletal muscle adaptations between interval training and moderate-intensity continuous training are summarized when possible. Lastly, this chapter highlights future topics for research that will provide further insight into the efficacy of interval training to elicit cellular adaptations relative to moderate-intensity continuous training.