Objective: To examine whether changes in cardiorespiratory fitness (CRF) following a physical activity (PA) intervention are associated with change in executive function (EF) and academic performance (AP) in children and adolescents. Design: Systematic review, meta-analysis, and meta-regression. Data sources: The databases Medline/PubMed, Science Direct, Scopus, SPORTDiscus, Academic Search Complete, CINAHL Complete, and PsychINFO were searched up to April 2019. Eligibility Criteria: Intervention studies that reported a pre- and a post-intervention measure of CRF and AP or EF and a control group were included. Results: A total of 15 studies were included. PA interventions had the following effects: 0.59 [95% CI = 0.08, 1.10] for CRF, 0.10 [95% CI = -0.18, 0.38] for AP, and 0.06 [95% CI -0.01, 0.14] for EF. For the sub-domains of EF: 0.04 [95% CI = -0.04, 0.12] for inhibition, 0.14 [95% CI = -0.06, 0.34] for working memory, and 0.00 [95% CI = -0.16, 0.16] for cognitive flexibility. The amount of change in CRF was not significantly associated with the interventions’ effect on AP (-0.32 [95% CI = -0.87, 0.23] (p=0.253)), or EF (-0.03 [95% CI = -0.24, 0.18] (p=0.811)). Conclusions: Positive effects were found for CRF after PA interventions. No effects were found for EF or AP and CRF change was not associated with their changes. However, it should be noted that most of the PA interventions occurred during curriculum teaching time, and no negative impact on EF or AP from the additional PA was found.