PER1 and metabolic syndrome: Therefore, because clock and per1 are the clock genes with a methylation level that did change at the end of the intervention (in the entire subject population, male group or metabolic syndrome) and which are implicated in associations with HPA activity, our hypothesis is that the BWRP-induced “chrono-resynchronization” involved not only metabolism in se (see above) but also the endocrine system, namely the HPA axis.