Nutrition Education and Behavioral Science
Our primary objective is to determine how mood response to exercise is influenced by genetic variation, controlling for exercise quantity and quality.
Methods : The Training Interventions and Genetics of Exercise Response (TIGER) Study is a prospective cohort study, in which sedentary subjects (18-35y, < 30min/wk for 30d prior to enrollment) participated in a 15-week program, exercising within a prescribed (65-85% maximum heart rate reserve) target heart rate zone for 3 d/wk. Before and after each exercise session, a subset of subjects (n=247) completed a 10cm visual analog scale (VAS: 0-100) for four mood states: fatigue, tension, depression, and hunger. Multiple linear regression was performed to examine the association between variation in DRD2, BDNF, and FTO genes and change in mood state following exercise, controlling for gender, exercise duration, and intensity.
Results : Exercise was associated on average with reduced feelings of fatigue (-3.18±16.37), tension (-3.85±12.97), and depression (-5.12±8.20), and increased feelings of hunger (6.06±10.54). Carriers of the major allele (A) in rs1362570 for the FTO gene experienced greater reductions in tension following exercise (AA or AG:-5.19±1.08 vs GG: -1.16±1.24, p< 0.02, respectively). Homozygotes for the major allele (A) in rs1799978 for the DRD2 gene displayed reduced feelings of tension in response to exercise, while those with one or more minor alleles reported increased tension (AA: -4.69±0.89 vs AG or GG: +2.25±2.16, p< 0.005). Homozygotes for the major alleles in rs151948, rs1362570, and rs1799978 (for BDNF, FTO, & DRD2 genes, respectively) served as strong predictors for changes in feelings of tension following exercise, controlling for gender and exercise parameters (p< 0.001). Subjects with one or more minor alleles (A) in rs1800498 for DRD2 gene displayed greater increases in hunger in response to exercise (AA or AG: 7.17±0.85 vs GG: 3.96±1.09, p< 0.03).
Specific gene polymorphisms, exercise intensity, duration, and gender may influence, in part, the variable mood response to exercise.
Funding Sources : Funding for this research was provided by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health Grant