Fig. 1
![Fig. 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs13102-020-00229-1/MediaObjects/13102_2020_229_Fig1_HTML.png)
Association between skeletal muscle mass and serum albumin concentration or BTR (N = 111). Comparisons of serum albumin concentration and branched-chain amino acid to tyrosine ratio (BTR) between the quartiles for skeletal muscle index (SMI) (a). The SMI quartiles were as follows: Quartile 1, SMI ≤ 11.0 kg/m2; Quartile 2, 11.0 < SMI ≤ 11.9 kg/m2; Quartile 3, 11.9 < SMI ≤ 12.5 kg/m2; and Quartile 4, SMI > 12.5 kg/m2. The groups were compared with Kruskal–Wallis tests and Bonferroni multiple comparison tests (*p < 0.05, **p < 0.01). Results of the Spearman’s correlation analyses between SMI and serum albumin concentration or BTR (b). Open circles represent control participants and closed circles represent wrestling athletes