The aim of this study was to evaluate the metabolic and autonomic parameters in trained youth obese mice. Female ob/ob mice (4 weeks old) were randomized into sedentary (OS, n=11) or trained (OT, n=8) (treadmill,5 days/w, 60 min/d, during 8 wks) groups. Blood glucose was measured by reagent strips. Blood pressure signals were recorded using a data acquisition system. The OT group had higher exercise capacity compared to the OS group. OT group had reduced body weight, white adipose tissue and blood glucose (45±2g, 6.1±1g and 133±3g mg/dL) compared to OS group (50±2g, 6.1±1g and 169±8 mg/dL). Exercise training improved glucose tolerance in trained group (OS: 27961±6501 vs. OT: 18258±6283 mg/dL/min). Mean arterial pressure and heart rate were similar between groups. The trained group showed increase in heart rate variability compared with sedentary group (OT: 50±12 vs. OS: 33±8ms2). Blood pressure variability and low frequency band were higher in OS group (23 ± 3mmHg2 and 7 ± 1 mmHg2) compared to OT (15 ± 2 mmHg2 and 5 ± 1 mmHg2). Moreover, the spontaneous baroreflex sensitivity, represented by alpha index, was lower in sedentary group (1.2 ± 0.3 ms/mmHg) compared to trained group (1.9 ± 0.2 ms/mmHg). In conclusion, our results suggest that physical training during lifespan can be effective inattenuating the increase in weight and blood glucose and improving blood pressure variability in obese mice.FAPESP 2011/20859–0