Association between apolipoprotein E gene polymorphisms and the effects of high-intensity interval training on body composition in university students

Objective This study examined the effects of APOE gene polymorphisms on body composition changes following high-intensity interval training (HIIT) in non-athletic Han Chinese university students from plain regions and identified genetic loci associated with HIIT sensitivity. Methods A total of 236 Han Chinese undergraduates from non-physical education majors completed a 12-week HIIT program (three sessions/week). Body composition was assessed before and after the intervention. Genomic DNA from white blood cells was genotyped using Illumina chips. Single nucleotide polymorphism (SNP) quality control and association analyses with body composition indices were performed using PLINK (v1.09) and SPSS 25.0, applying linear regression and ANOVA with least significant difference (LSD) post hoc tests ( p < 0.05). Results (1) Of 22 initial APOE SNPs, five passed quality control; the rs405509 locus was associated with HIIT-induced changes in body composition. (2) The GG genotype at rs405509 was associated with higher baseline BMI overall and with higher baseline weight, BMI, and waist-to-hip ratio in females than the TT genotype. (3) After training, GG carriers showed greater reductions in overall body fat than GT/TT carriers ( p < 0.05), and female GG carriers exhibited greater improvements in weight, body fat, and BMI. (4) In the Bonferroni post hoc analysis, compared with the TT group, the GG group showed significantly lower body weight (MD = −1.95, 95% CI: −3.374 to −0.533, p = 0.003), weight percentage (MD = −3.44, 95% CI: −6.070 to −0.819, p = 0.006), and BMI (MD = −0.70, 95% CI: −1.264 to −0.139, p = 0.009), while the difference in skeletal muscle percentage was not significant ( p = 0.107). Compared with the GT group, the GG group also had significantly lower body weight, weight percentage, skeletal muscle percentage, and BMI ( p = 0.02–0.03). No significant differences were observed between the GT and TT groups (all p > 0.05, with 95% CIs crossing zero). (5) The rs405509 locus was significantly associated with HIIT sensitivity for body fat ( p = 0.01873). Conclusion The rs405509 locus of the APOE gene is associated with body composition responses to HIIT, and female GG carriers show heightened responsiveness.