Improved assessment of the global transcriptional response to endurance exercise in human skeletal muscle

Endurance exercise is a potent stimulus for mitochondrial biogenesis and cellular metabolism. While the molecular events surrounding an acute bout of endurance exercise have been previously evaluated using small‐scale approaches, recent advances in gene microarray technology have substantially improved the number of gene targets available for investigation. Therefore, the purpose of this study was to examine the global mRNA response to a single bout of endurance exercise. Eleven healthy, young men (age 22±1 yrs, VO 2peak 46±2 ml·kg −1 ·min −1 ) were recruited for this investigation. Muscle samples were acquired prior to and at 30 mins and 3 hours following an exhaustive cycling protocol. At 30 mins post‐exercise 404 genes were differentially expressed from rest (P<0.05), while at 3h 846 genes were significantly altered (P<0.05). When clustered by biological function, the greatest enrichment of genes at 30 mins occurred in those relating to developmental processes, cell differentiation, DNA binding, negative regulation of cellular processes, and primary metabolic processes. At 3h, functional annotation revealed clusters related to developmental processes, signal transduction, anatomical structure development, DNA binding and the regulation of apoptosis. To date, these data provide the most comprehensive transcriptional approach regarding the acute effects of endurance exercise. (Supported by NSERC Canada).