Characteristics and comparison of participants (n = 20) separated into two groups based on NAA/Cr in cPMC.

Data presented as mean±standard deviation where applicable. Cr: creatine; cPMC: caudal primary motor cortex; NAA: N-acetylaspartate; *Comparisons between participants with NAA/Cr≤1.17 and participants with NAA/Cr>1.17 based on Mann-Whitney U-test or Chi-square, as appropriate; †Measured while steady-state walking and counting backwards by seven; ‡body mass index <21 kg/m2; ||Manolio scale; §Serum 25-hydroxyvitamin D <75 nmol/L; ¶Spring from 21 March to 20 June; Summer from 21 June to 20 September; Fall from 21 September to 20 December; and Winter from 21 December to 20 March; P significant (i.e. <0.05) indicated in bold.