FIGURE 2.

Global metabolomic responses to acute fatiguing exercise in equine skeletal muscle. (A) Three-dimensional PCA plot of skeletal muscle biopsy samples in the unconditioned state. Spheres denote pre-exercise (Pre), cones denote 3 h post-exercise (3 h), and cubes denote 24 h post-exercise (24 h). The plot reveals little discrimination between the time points with Component 1 (16.35%), Component 2 (13.06%), and Component 3 (10.86%). (B) Hierarchical clustering heatmap supports the findings from PCA plot (A) and revealed that samples originating from the same horse clustered close together rather than around a given time point. White boxes denote Pre, pink boxes denote 3 h, and red boxes denote 24 h. Green, blue, light blue, orange, gray, salmon, tan, and teal colors each signify an individual horse. (C) Three-dimensional PCA plot of skeletal muscle biopsy samples in the conditioned state. The plot reveals a better discrimination of horses between time points with Component 1 (24.31%), Component 2 (13.44%), and Component 3 (7.91%). (D) Hierarchical clustering heatmap of skeletal muscle biopsy samples in the conditioned state. Heatmap supports findings from PCA plot (C) and revealed that samples tended to cluster around a given time point rather than horses clustering with themselves. n = 8 per group.