RESUMO
Objective To compare the effects of strength training with load progression after 4 weeks on sleep parameters and mental health in college students. Methods A total of 17 university students (11 women, 6 men), ranging from 18 to 21 years old, were randomized into a strength training group (STG) and a control group (CG). The Pittsburgh sleep quality index (PSQI), insomnia severity questionnaire, hospital anxiety and depression (HAD) scale, profile of mood states (POMS), and chronotype were used to evaluate the main outcomes. Training consisted of 60 minute·d -1 (2 times/week, for 4-weeks), with 3 sets of 10 to 12 repetitions, and a 1-minute rest interval between sets and exercises. Baseline and postintervention differences were analyzed using generalized estimating equations (GEE). Results After 4 weeks of ST, a significant time effect on the chronotype (ß: 1.33; p < 0.05) was observed in the STG. Additionally, there was a significant time and group effect in the reduction of tension (ß: 5.00; p < 0.05), depression (ß: 15.41; p < 0.05), anger (ß: 8.00; p < 0.05), and confusion (ß: 6.50; p < 0.05). For fatigue (ß: 2.66; p < 0.05), there was a significant time effect difference in its reduction. Vigor was meaningfully increased in the STG group (ß: -1.75; p < 0.05). Furthermore, a significant positive relationship was observed between sleep quality and anxiety (r = 0.54; p = 0.03). Finally, insomnia was positively related with an increase in confusion (r = 0.70; p = 0.04) and anxiety (r = 0.52; p = 0.04), as well as with a decrease in vigor (r = -0.71; p = 0.03). Discussion Short-term strength training for 4 weeks was effective for improving mental health, helping achieve characteristics of a positive mood profile, that is, low values for negative factors and a high value for the positive factor.
RESUMO
BACKGROUND: Academic achievement (AA) is an important issue not only during the school period since it is a strong predictor of long-term professional and social success. Physical fitness (PF) components are associated with AA, and previous studies were conducted with relatively small samples, lack of statistical power, and the conclusions are based on simple correlational analyses. The objective of this study was to analyze the association between PF (single and clustered) with AA in a large and representative sample of high school students. METHODS: Cross-sectional design study conducted with 911 students, aged 13-15 years (38.52% boys) enrolled in the first year of high school. Cardiorespiratory fitness (20-m shuttle run test), muscular strength (dynamometer), and body composition (skinfolds) were measured. PF components were clustered (Z-cardiorespiratory fitness + Z-muscular strength - Z-body fatness). AA was analyzed through standard math tests. Hierarchical linear regression analysis was applied to verify the independent contribution of each single component and PF's cluster on AA. Age, screen time, maternal education, race, and type of residence were used as covariates. RESULTS: Among boys, cardiorespiratory fitness was negatively associated with AA (ß = -0.137; P = .041), while strength was positively associated with AA (ß = 0.188; P = .004). There was no association between clustered PF indicators and AA (ß = 0.064; P = .297). There was a negative association between age and AA in girls (ß = -0.151; P = .003) and in boys (ß = -0.128; P = .045). CONCLUSIONS: These results support current literature, indicating an association between PF's component, namely muscular strength and AA (mathematics) in adolescents, even when controlled for several covariates.
