Effects of Conventional Exercise and Virtual Reality Exergaming on Executive Functions in Adults with ADHD: An fNIRS Study

The current project aims to explore the effects of conventional exercise versus virtual reality (VR) exergaming on prefrontal cortex hemodynamic responses and executive functions (EFs) in adults with ADHD. Individuals with ADHD often show EF deficits linked to dysfunction in the dorsolateral prefrontal cortex (DLPFC) (Wu et al., 2023). Exercise has been shown to improve cognitive processes in this population, in part by increasing catecholamine release, particularly dopamine during physical activity, thereby mimicking the effects of stimulant medication (Rassovsky & Alfassi, 2019). Moreover, the National Institute for Health and Care Excellence (NICE) recommends regular exercise as part of ADHD symptom management (NICE, 2018). Building on this, the present study explores behavioural and hemodynamic responses differences from pre to post in the VR exergaming condition compared to conventional exercise. VR provides an immersive and engaging environment that incorporates visual, tactile, and auditory feedback, making it a promising tool for therapeutic and rehabilitative applications (Runswick et al., 2024). A recent meta-analysis found that VR-based sports produced meaningful improvements in executive functions, particularly in task-switching and attentional control among individuals with ADHD (Zhang, Li, & Sheng, 2024). Task-switching involves the ability to adapt to changing environmental demands and is especially well supported in VR exergames due to their unpredictable nature. Additionally, a meta-analysis involving older adults with and without cognitive impairments showed that while exergaming led to improvements in global cognition compared to conventional exercise, it did not outperform conventional exercise on more specific cognitive domains (Soares et al., 2021). To date, no studies have directly compared the neurophysiological and behavioural effects of conventional exercise versus VR exergaming in adults with ADHD which is an under-researched population. One study by Tiriyaki et al. (2024) examined the effects of single of moderate intensity aerobic exercise on brain activation using fNIRS and behavioural performance during a Go/No-Go task in adolescents with ADHD compared to controls. They found that adolescents with ADHD showed poorer baseline task performance and lower prefrontal activation than controls. After the exercise condition, both groups showed improvements in attention related measures, such as increased correct responses in Go trials and reduced omission errors. fNIRS data showed that in post-exercise, the between-group differences in prefrontal activation during inhibition trials disappeared. However, their study did not compare VR exergaming with conventional exercise, so it remains unclear whether one modality outperforms the other. The present study addresses this gap by exploring the effects of both exercise modalities on DLPFC activity and behavioural outcomes to determine which is more effective and feasible for this population.