Study limitations
This study has some limitations. First, although we randomly assigned participants to two trials, the intervention was not performed in a blinded manner, which might have caused bias in the results. Second, we did not evaluate whether acute SJL altered circadian variables, such as clock gene expression levels and circadian-regulated hormones. Therefore, the present study could not clarify whether the intervention caused circadian disruption. Third, self-reported energy intake might be underestimated because the energy intake was low relative to energy expenditure throughout the intervention. Fourth, because only healthy male participants were recruited for the present study, the generalizability of our findings to other populations is limited. Future studies should be performed to solve these limitations.