Changes in 24-h Movement Behaviors During Relationship and Parenthood Transitions: A Compositional Data Analysis

Area of Science:

• Behavioral science
• Public health
• Chronobiology

Background:

• Young adulthood involves significant life transitions, including relationship formation and parenthood.
• These transitions can impact daily routines and health behaviors, yet few studies use objective measures to track changes in 24-hour movement behaviors.
• Understanding these changes is crucial for public health interventions.

Purpose of the Study:

• To examine how relationship and parenthood transitions affect the composition of 24-hour movement behaviors in young adults.
• To identify specific changes in sleep, sedentary behavior (SED), light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) during these life stages.

Main Methods:

• Utilized wrist-worn accelerometers to objectively measure movement behaviors over one week in 170 young adults at ages 26 and 31.
• Categorized participants based on relationship status (single, transitioning, partnered, separated) and parenthood status (non-parents, new parents, parents).
• Employed compositional linear mixed models to analyze changes in the distribution of daily movement behaviors.

Main Results:

• Overall, light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) decreased relative to sleep and sedentary behavior (SED).
• Individuals transitioning to a partnership showed a decrease in MVPA, while partnered and separated individuals reduced LPA.
• New parents decreased MVPA, whereas established parents increased it, indicating varied impacts of parenthood on physical activity.

Conclusions:

• Relationship and parenthood transitions significantly alter young adults' 24-hour movement behavior composition.
• Becoming a first-time parent or starting a relationship was associated with a decline in MVPA.
• Interventions should consider these life transitions to support sustained physical activity levels.