The Relationship Between Cardiorespiratory Fitness And Resting-State Cortical Activation In Children: An Eeg Study On Power Spectrum Density

PURPOSE: Although cardiorespiratory fitness (CRF) is known to have positive impact on cognitive performance and performance-related brain functioning during childhood development, it remains unknown whether CRF-related cognitive benefits extend to children’s resting-state brain function assessed by electroencephalogram (EEG). This study aimed to determine the relationship between CRF and resting EEG power in children. METHODS: A total of 109 children between 8-10 years old (45 females; age = 9 ± 1 years) completed a graded exercise test to assess V̇O2max to measure CRF, followed by resting-state EEG recordings under eyes-open and eyes-closed conditions in counterbalanced order). Individual alpha frequency was identified to individually define brain oscillation frequency bands— delta, theta, alpha-1, alpha-2, upper alpha, beta1 and beta2 — to accounting for variability in EEG rhythms due to developmental difference. Hierarchical regression analyses assessed the relationship between V̇O2max and EEG power in each of the frequency bands during eye-open and eye-close conditions while controlling for age, sex, body mass index, and intelligence quotient. RESULTS: V̇O2max was positively associated with power in alpha1 (F = 17.292, ∆R2 = 0.136, p = 0.001), alpha2 (F = 40.524, ∆R2 = 0.271, p = 0.001), upper alpha (F = 24.273, ∆R2 = 0.186, p = 0.001), and beta1 (F = 4.418, ∆R2 = 0.040, p = 0.013) but not delta, theta, and beta2 bands across the eye-open and eye-close conditions, despite EEG power across all frequency bands was lower during eyes-open than eyes-closed condition. The interaction between V̇O2max and visual condition (open vs. close) was not significant across all frequency bands. CONCLUSION: The positive associations of V̇O2max with increased EEG power selectively in fast frequencies suggest that having higher CRF levels may reflect improved oxygen delivery to the brain and in turn enhance the neural efficiency and internal attentional processes regardless of the presence of visual input. By extending the cognitive benefits of CRF to resting-state brain function, this study underscores the importance of fitness for brain health and highlights the need for further research to understand the CRF-EEG relationship across diverse populations and developmental stages.