Leptin and leptin receptor genetic variants associate with habitual physical activity and the arm body composition response to resistance training

We investigated the influence of Leptin (LEP) and leptin receptor (LEPR) SNPs on habitual physical activity (PA) and body composition response to a unilateral, upper body resistance training (RT) program. European-derived American volunteers (men=111, women=131, 23.4±5.4yr, 24.4±4.6kg·m−2) were genotyped for LEP 19 G>A (rs2167270), and LEPR 326 A>G (rs1137100), 668 A>G (rs1137101), 3057 G>A (rs1805096), and 1968 G>C (rs8179183). They completed the Paffenbarger PA Questionnaire. Arm muscle and subcutaneous fat volumes were measured before and after 12wk of supervised RT with MRI. Multivariate and repeated measures ANCOVA tested differences among phenotypes by genotype and gender with age and body mass index as covariates. Adults with the LEP 19 GG genotype reported more kcal/wk in vigorous intensity PA (1273.3±176.8, p=0.017) and sports/recreation (1922.8±226.0, pA and LEPR 668 A>G associated with habitual PA and the body composition response to RT. These LEP and LEPR SNPs are located in coding exons likely influencing LEP and LEPR function. Further investigation is needed to confirm our findings and establish mechanisms for LEP and LEPR genotype and PA and body composition associations we observed. ► We examined genetic variation and its association with physical activity levels. ► Leptin and Leptin Receptor SNPs were the genetic variants examined. ► LEP19 G>A associated with habitual physical activity. ► LEPR 668 A>G associated with the body composition response to resistance training.