4%; CR, 31.8%; TR, 24.7%; and TRCR, 28.2%), and final weights were not significantly different between groups. Final BW was as follows: CO, 419.8 ± 40.6 g; CR, 402.7 ± 51.8 g; TR, 394.4 ± 34.5 g; and TRCR, 403.5 ± 17.3 g, P > .05. These results show that Cr supplementation

and resistance training did not affect the BW of animals; the increase in BW increase reflected only the somatic growth of animals. Furthermore, no difference in weekly food intake was found between groups (CO, 408 ± 13 g; CR, 410 ± 20 g; TR, 390 ± 19 g; and TRCR, 416 ± 16 g, P > .05), indicating that the independent variables (training and Cr) did not interfere with developmental aspects of the animals. A representative HE staining used to measure the soleus muscle fiber selleck CSA is shown in Fig. 2, and the corresponding data are presented in Fig. 3. Protease Inhibitor Library supplier Resistance training promoted a significant (P < .05) 37% increase

in muscle fiber CSA of the TR group compared with the CO group (mean area: TR, 3425 ± 534 vs CO, 2507 ± 508; P < .05) ( Fig. 3). Interestingly, this hypertrophic increase remained unchanged when Cr supplementation was added to the resistance training (mean area: TR, 3425 ± 534 vs TRCR, 3398 ± 509; P > .05) ( Fig. 3). Moreover, the Cr supplementation alone did not promote any significant alteration in muscle fiber CSA (mean area: CR, 2540 ± 486 vs CO, 2507 ± 508; P > .05) after 5 weeks of experimentation ( Fig. 3). In addition to an increase in muscle fiber CSA, the resistance training promoted a significant

(P < .05) increase of 16% and 21% in MW and MW-to-BW ratio, respectively ( Table 1). However, this increase remained unchanged when Cr supplementation was added to the resistance training ( Table 1). Moreover, Cr supplementation alone did not promote any significant (P > .05) alteration in MW and MW-to-BW ratio ( Table 1) after 5 weeks of the experiment. The wet-to-dry ratio of the soleus muscle was also measured to evaluate the status of muscle hydration. The wet-to-dry ratio of the soleus was not affected by resistance training or Cr treatments Y-27632 2HCl (CO, 3.48 ± 0.10; TR, 3.29 ± 0.20; CR, 3.45 ± 0.16; P > .05). The major finding of this study was that Cr supplementation does not promote any additional hypertrophic effect on skeletal muscle fiber CSA when supplemented trained muscles are required to perform the same workload that the nonsupplemented trained muscles. Specifically, Cr supplementation does not promote any direct anabolic effect on the skeletal muscle during resistance training. Previous studies have reported that Cr supplementation can promote an increase in muscle mass during resistance training with the progressive increase of overload [6] and [9]. This anabolic effect has been attributed to the ability of Cr to allow supplemented muscles to perform training with a higher load than nonsupplemented muscles [8] and [10], suggesting an indirect hypertrophic effect of Cr loading on muscle mass.