Health-Related Fitness as a Predictor of Anxiety Levels Among School Adolescents: An observational cross-sectional study

Background: There is an inverse association between cardiorespiratory fitness and general anxiety levels in adolescents. Obesity also is associated with a higher risk of anxiety in this population. However, little is known about the association between other health-related fitness elements with anxiety symptoms in this population. The authors explored the relationship between health-related fitness and anxiety symptoms in a large sample of Brazilian youth. Methods: This was an observational cross-sectional study with a sample comprised of 257 school adolescents, who were 136 girls (52.9%) and 121 boys (47.1%). The health-related fitness elements were evaluated by FitnessGram® test and anxiety levels by Multidimensional Anxiety Scale for Children-39. Hierarchical regression analyses were used to determine the association between health-related fitness elements and anxiety symptoms in both sexes. Results: In male adolescents, only the cardiorespiratory fitness was significantly associated with anxiety symptoms (F_{(1, 119)} = 6.472; P = 0.012; R² = 0.052; adjusted R² = 0.044). In turn, the anxiety symptoms showed an inverse small relationship with cardiorespiratory fitness (r =-0.227; P < 0.01). However, in female adolescents, no association was found between health-related fitness elements and anxiety symptoms. Conclusion: The level of cardiorespiratory fitness may represent a marker of anxiety in male adolescents.