In end points for which a decrease indicated an improvement of a test result, a sign reversal was performed to allow comparison. AA indicates amino acids; BCAA, branch chain amino acids; Cit/Met, citrulline and metformin combination therapy; D1, first dimension of the MFM, referring to transfer and standing posture; EAA, essential amino acids; FF, fat fraction; MFM, Motor Function Measure; NEAA, nonessential amino acids; qMRI, quantitative magnetic resonance imaging; 6-MWD, 6-minute walking distance; and T2, transverse weighted relaxation time.