The purpose of this study is to examine how participating in exercise together versus separately influences brain function, cognitive performance, mood, and parent-child connection in mother-child dyads. Mothers and their children will complete two fitness class visits at a participating community fitness facility/CrossFit affiliate. During one visit, mothers and children will exercise in separate age-appropriate classes, and during the other visit they will exercise together in a shared class. Before and after each exercise session, participants will complete brief assessments of cognition, mood, and brain activity using a portable electroencephalography (EEG) device. Findings from this pilot study will help determine the feasibility of conducting community-based neuroscience research and may inform future family-centered physical activity programs designed to support brain, emotional, and social health.

Physical activity is associated with improvements in cognitive function, emotional well-being, and overall health across the lifespan. Emerging evidence suggests that social and relational contexts may influence the benefits derived from physical activity, yet little research has examined how exercising together versus separately affects parent-child dyads. Understanding these effects may inform the development of family-centered physical activity interventions that promote both physical and psychological health.

The purpose of this pilot study is to evaluate the feasibility of conducting community-based neurocognitive research within fitness settings and to explore acute changes in cognitive, emotional, and neurophysiological outcomes following exercise. Mother-child dyads will participate in two exercise conditions: a shared exercise session in which mothers and children participate together, and a separate exercise session in which mothers and children participate in age-appropriate classes independently. A within-subjects design will allow each dyad to experience both conditions.

Cognitive performance, mood, and brain activity will be assessed before and after exercise using brief computerized assessments and portable electroencephalography (EEG). Feasibility outcomes will include recruitment, retention, adherence, participant acceptability, and data quality. Exploratory analyses will examine whether exercise context (shared versus separate participation) is associated with differences in cognitive, emotional, and neurophysiological responses.

Findings from this study will provide preliminary data to support future investigations of family-based physical activity interventions and their potential effects on brain health, emotional well-being, and parent-child relationships.

Inclusion Criteria

• Adult participant is a mother or female primary caregiver aged 18 years or older.
• Child participant is at least 3 years of age.
• Mother and child are willing to participate together as a dyad.
• Mother and child are able to understand and speak English.
• Mother and child are willing to attend two study visits at a participating community fitness facility.
• Mother and child are able to safely participate in moderate-to-vigorous physical activity as determined by health screening procedures.
• Mother is willing to provide informed consent and child is willing to provide assent when appropriate.

Exclusion Criteria *Mother*

• Pregnancy at the time of participation.
• Any cardiovascular, metabolic, respiratory, neurological, musculoskeletal, or other medical condition that would make exercise unsafe.
• Current injury or physical limitation preventing participation in exercise.
• History of seizure disorder or other condition that may interfere with EEG assessment.
• Inability to complete study procedures or wear EEG equipment. *Child*
• Medical condition, injury, or physical limitation that would make participation in exercise unsafe.
• Neurological condition or developmental disorder that would prevent completion of study procedures, as determined by the parent and study team.
• History of seizure disorder or other condition that may interfere with EEG assessment.
• Inability to tolerate wearing the EEG headset or complete study procedures. *Dyad*
• Either the mother or child is unable or unwilling to complete both study visits.
• Either participant has a contraindication to exercise identified during screening.
• Either participant has a condition that, in the opinion of the investigators, would make participation unsafe or compromise data quality.

Individuals who self-identify as women and serve as a parent, guardian, or primary female caregiver of an eligible child are eligible to participate in the adult participant role. Children of any gender identity are eligible to participate.

Individual participant data will not be made publicly available because the study involves a small sample size and includes potentially identifiable cognitive, physiological, and neurophysiological data from mother-child dyads. Data will be reported in aggregate form to protect participant confidentiality and privacy.