The purpose of this study was to examine whether leptin levels affect the response of leptin to exercise training (ET) and whether this is also affected by C-reactive protein (CRP) or the three common Apolipoprotein E genotypes (APOE). Ninety-seven (male = 45, female = 52) sedentary individuals underwent 6 months of supervised ET. Blood was sampled before the initiation of ET, and again 24 and 72 hr after completion of the final training session. ET resulted in a small reduction in body mass (80.47 ± 18.03 vs 79.42 ± 17.34 kg, p < .01). Leptin was reduced 24 hr after the final exercise session (p < .01), but returned to normal after 72 hr (p > .05)—Pre: 13.51 ± 12.27, 24hr: 12.14 ± 12.34, 72hr: 12.98 ± 11.40 ng/ml. The most hyperleptinemic individuals had a greater initial response, which was sustained through to 72 hr after the final session in the pooled study population (p < .01), and in both males (p < .05) and females (p < .05) separately. CRP was related to leptin independently of body weight and positively related to the reductions in leptin. APOE genotype was not related to leptin levels and did not affect the response to ET. Leptin levels may only be reduced by ET in those with hyperleptinemia. In addition, both the initial extent of hyperleptinemia and the subsequent reduction in leptin may be related to low grade chronic systemic inflammation.
Lowndes and Angelopoulos are with the Dept. of Health Professions, University of Central Florida, Orlando, FL. Kyriazis is with the Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, FL. Zoeller is with the Florida Atlantic University, Davie, FL. Miles is with the Dept. of Health and Human Development, Montana State University, Bozeman, MT. Seip and Thompson are with the Genetics Research Center, Hartford Hospital, Hartford, CT. Moyna is with the Dept. of Health and Human Performance, Dublin City University, Dublin, Ireland. Visch is with the Dept. of Exercise and Sport Performance, University of New England, Biddeford, ME. Pescatello is with the Kinesiology & Human Performance Laboratory, University of Connecticut, Storrs, CT. Gordon is with the Dept. of Health, Human Performance and Recreation, Baylor University, Waco, TX.