High-Intensity Training in Racehorses Results in ____

High-intensity training in racehorses results in ____.

A) the expression of genes involved in energy metabolism, insulin response, and muscle inflammation ​
B) the expression of genes involved in metabolism, oxidative phosphorylation, and muscle structure
C) no phenotypic or biochemical changes
D) no change in the expression of genes, but changes in phenotypes
E) changes in the expression of genes, but no changes in phenotypes