Caloric restriction (CR) and exercise (EX) attenuate metabolic impairment in obesity. High cardiorespiratory fitness (CRF) also protects against metabolic syndrome. However, the interplay between CRF, obesity, CR, and EX on metabolic health remains unclear. Male rats were fed with either a normal diet (ND; n=6) or a high-fat diet (HFD; n=30) for 12 weeks. Baseline CRF was measured. Then, ND-fed rats received a ND for 16 more weeks. HFD-fed rats were divided into 5 groups (n=6/group) to receive either a HFD for 16 weeks (OB) , 40% CR for 6 weeks followed by an ad lib ND for weeks (CR-S) , 40% CR for 16 weeks (CR-L) , a HFD + an EX for 6 weeks followed by a ND without EX for weeks (EX-S) , or a HFD + an EX for 16 weeks (EX-L) . Then, anthropometry and blood metabolic parameters were evaluated. We found that CR and EX decreased insulin resistance and dyslipidemia in obesity. High baseline CRF was correlated with favorable anthropometry and metabolic profiles at follow-up in the ND, OB, CR-S, CR-L, and EX-S rats. However, these correlations were not shown in the EX-L rats (Figure) . Our findings suggested that high CRF also protects against metabolic impairment in obesity, regardless of CR or short-term EX. Hence, an enhancement of CRF may provide the better effective therapy for obesity. Otherwise, low-CRF people may get the greatest benefit on a protection against metabolic syndrome by long-term EX.
P. Pantiya: None. S.C. Chattipakorn: None. N. Chattipakorn: None.