ALS reduces muscle strength (−70% between 11 and 15 weeks, p < 0.05), modulates muscle metabolism through lowering citrate synthase (CS) (−30% vs. WT, p = 0.0007) and increasing cytochrome c oxidase and malate dehydrogenase activities, and elevates oxidative stress markers in skeletal muscle. Here, PHGDH is linked to amyotrophic lateral sclerosis.