Association of IGFBP3-185C＞T Genetic Polymorphisms with the Muscle Strength Response to Resistance Training

Objective:To explore the associations between the insulin-like growth factor binding protein 3(IGFBP3-185C>T polymorphisms and the muscle strength response to a unilateral,upper arm resistance-training program among healthy,young adults.Methods:A total of 600 healthy young adults from university in Fujian province were included in the present study.Participants' information and data were obtained by a standard questionnaire.Polymorphisms of IGFBP3-185C>T were detected by Taqman single nucleotide polymorphism(SNP) allelic discrimination by means of an ABI7900HT.All subjects performed a training program of the nondominant(trained) arm with the dominant(untrained) arm as a comparison.Peak elbow flexor strength was measured with one repetition maximum,isometric strength with maximum voluntary contraction,and bicep cross-sectional area with MRI in the trained and untrained arms before and after training.Results:there existed a connection between IGFBP3-185C>T gene polymorphism and muscle strength response at;after resistance training,in male and female subjects,the MVC values of CC genotype individual trainers respectively increased by 22.5% and 24.5%,meanwhile,in the two groups of subjects,the variation of MVC value of CC genotype individual trainers was obviously higher than that of CT and TT genotype individuals(P<0.05);in female subjects,the 1-RM value of CC genotype individual trainers and CSA value of trainers respectively increased by 17.4% and 21.1%;meanwhile,both-RM value of CC genotype individual trainers and CSA value of trainers increased compared with CT+TT genotype individuals(P<0.05);it was found from the further research that with the increasing of T allele,the MVC value of male and female trainers and the variable as well as 1-RM of female non-trainers and CAS value of trainers all gradually reduced,it was found that there existed a dose-effect relationship(P<0.01) through trend test.Conclusion:The IGFBP3 C185 allele may increase more muscle strength response to training in men and women.