Internet gaming disorder (IGD) has emerged as a severe mental health issue that needs to be addressed [12]. Both the DSM-5 (The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) and ICD-11 (The International Classification of Diseases, 11th Revision) define this disorder as a repetitive or continuous gaming behavior pattern that lasts for at least 12 months, unless severe symptoms occur [3-5]. IGD can lead to severe negative consequences for players, including neurocognitive deficits, impaired executive functioning, and emotional dysregulation [67], which in turn generate physical, psychological, and behavioral effects on players.

 Neuroimaging studies have identified significant alterations in functional brain networks associated with IGD [8], including impaired executive control over gaming cravings and strong gaming cravings in reward processing-related brain regions [910]. Multiple studies have observed relatively decreased functional connectivity (FC) between executive-control–related and reward-related regions [1112]. One study found that the IGD group showed decreased FC between the right superior frontal gyrus (SFG) and right posterior insula compared to controls [13]. Another found that the IGD group showed significantly decreased FC values between the right middle frontal gyrus (as well as dorsolateral prefrontal cortex; DLPFC) and the right anterior cingulate cortex [1114]. Moreover, reduced FC strength revealed weakened connectivity in executive-control–related regions, including SFG-DLPFC [15] and DLPFC-postcentral gyrus [16].

 Traditional interventions for IGD have focused mainly on psychological, pharmacological, and exercise-based therapies [17]. These treatment strategies need to perform by professional trained psychiatrist and usually expensive and hard to perform. Comparing with these treatment strategies, the exercise-based interventions may be more practical [18] as it is widely acceptable and easily performed in daily life. Exercise intervention, such as the aerobic exercise, is known to increase brain-derived neurotrophic factor, and the increased brain-derived neurotrophic factor enhances cognitive function by modifying neurotransmission, stimulating neurogenesis, and promoting synaptic plasticity in the brain [19]. Aerobic exercise has been proven to restore and regulate nerve cells, enhancing their adaptability to external variations, and optimizing cognitive abilities, executive functions, and inhibitory control, while fostering positive effects and mitigating negative impacts [20-22]. In previous studies on aerobic training for IGD, Liu et al [23] found through systematic review and meta-analysis that mind–body exercises like Tai Chi and Qigong can significantly improve executive function. In a study of training on brain function in methamphetamine addicts, aerobic training temporarily altered the activation of neural networks in the reward system of drug-dependent individuals, effectively inhibiting their drug craving [24]. Rensburg et al [25] explored the effects of training on the brain during withdrawal and suggested that individuals exercising 15 hours after quitting smoking show significant reductions in smoking craving and significant activation of the brain reward system. Meanwhile, physical training normalizes dopaminergic and glutamatergic transmissions [26]. Cannabinoids are thought to play a crucial role in mediating the mood-regulating effects of exercise [27], while mGluR5 is pivotal for the central reward processing in addicted individuals [28]. These evidence supports the hypothesis that aerobic training mitigates IGD by restoring the functional balance between the reward and control networks, a process potentially mediated by its synergistic effects on dopaminergic, glutamatergic, and endocannabinoid systems.

 Although extensive research underscores the therapeutic potential of exercise, the neurofunctional effects of fixed, progressive aerobic training (PAT) regimens in individuals with IGD remain uncharted in the published literature. A study on morphine-addicted rats shows that compared to the fixed aerobic protocol, progressive aerobic exercise significantly outperformed in reversing morphine-induced impairments in memory, memory consolidation, and locomotor activity [29]. One study suggests that 24-week PAT could significantly improve the anxiety symptoms, psychological pressure and sleep state of male drug addicts [30]. However, the specific impact of PAT on the neural mechanism with IGD remains unclear.

 Both regional homogeneity (ReHo) and degree centrality (DC) are two main resting-state functional magnetic resonance imaging metrics in a way of voxel-wise whole-brain analysis [3132]. ReHo is a voxel-based measure of brain activity that estimates the degree of synchronization between the time series of a given voxel and its nearest neighbors [3334]. The validity of this measure is based on the premise that intrinsic brain activity primarily reflects the coordinated activation of voxel clusters rather than isolated single voxels. Consequently, higher ReHo values are thought to represent greater synchronization of local field potentials associated with neuronal activity in the human brain [35]; DC considers Pearson correlation coefficient as metric for FC estimation between each pair of voxels, assigning to each voxel the global number of functional connections between it and all other voxels across the brain [36]. In its more diffuse implementations, it involves the use of a threshold over which a pair of voxels is considered connected [3738]. The combination of ReHo and DC captures both local and remote neural synchronization [39], demonstrating superior performance over traditional methods for selecting regions of interest (ROIs) in resting-state functional magnetic resonance imaging (fMRI) [4041].

 While IGD research has not employed PAT intervention, dance as a sport enhances frontal-striatal circuit connectivity in individuals with IGD [23]. Research on heroin addiction further suggests that physical exercise serves as an effective non-pharmacological intervention, capable of improving patients’ executive control function [42]. Therefore, this study evaluated the efficacy and neural mechanisms of PAT on IGD through FC and correlation analysis. We hypothesized that PAT would reduce the severity of game craving and addiction severity in IGD by altering the FC of brain regions involved in executive control network (ECN) and reward network (RN).