Sense of Humor and General Life Satisfaction in Association with the Biological Effects of Resistance Training in People with Impaired Glucose Tolerance

The aim of the study was to investigate associations between psychological and biological changes due to resistance training in people with impaired glucose tolerance (IGT). Subjects were randomized into maximal (MRT) versus endurance resistance training (ERT) groups. Intervention periods lasted four months. All subjects had blood work that suggested IGT at the initial screening. The ERT acted as a wait-list control group when the MRT performed their training. Baseline scores on general life satisfaction (LISAT) and sense of humor (SHQ-6: a positive coping resources) were obtained. Potential differences between groups (types of intervention and intervention versus control) were investigated by analysis of variance (one-way ANOVA). Correlations were calculated in each group to estimate the degree of covariance between biological and psychological changes from pre- to post-intervention by Pearson and Spearman coefficients. Sense of humor tended to be correlated with a positive reduction of insulin following MRT as well as with reduction in body fat following ERT. Differences across the intervention groups in changes from pre- to post-training in biological variables (glucose, insulin, muscle mass, and corrected percentage of fat) as well as psychological variables (general life satisfaction and sense of humor) were not significant, whereas differences in BMI and weight were significant. By investigating the intervention groups separately in comparison to the control group, the MRT revealed significant improvement by reduction in insulin, percentage of fat, BMI and weight. The ERT caused significant improvements for insulin and percentage of fat, while general life satisfaction had a significant negative development.