The impact of an eight-week online physical activity intervention on sleep quality in early pregnancy: A pilot study...

Sleep disturbances are common in pregnancy and linked to adverse maternal and fetal outcomes. Physical activity is a promising non-pharmacological strategy to improve sleep; however, few studies have objectively examined this relationship during early pregnancy. This pilot study examined whether participation in an eight-week, online, participant-centered physical activity program (Healthy Mamas Program) was associated with changes in objectively measured sleep among pregnant Australian women in their first trimester.

A prospective intervention study was conducted between March 2021 and November 2022. Eleven women who were not regularly active at baseline (<75 minutes/week) wore Fitbit Charge 2 devices to track daily physical activity and sleep. Participants completed a seven-day baseline assessment, followed by the eight-week intervention and a seven-day post-program assessment. Sleep and physical activity variables were transformed as appropriate. Descriptive statistics, Pearson correlations, and linear mixed-effects models were used to assess associations and changes over time.

Participants engaged in 244.50 minutes of total physical activity per day, primarily of light intensity. No significant change in physical activity was observed over time (p=0.17). Participants averaged 5.9 hours of sleep per night, with 23.18 nightly awakenings and a mean sleep efficiency of 78.91%. There were no significant associations between physical activity and sleep duration (p=0.130) or efficiency.

Findings suggest that, while feasible, the intervention did not significantly improve physical activity or sleep. Both behaviors remained below recommended levels. These results highlight the need for trimester-sensitive, accessible interventions to promote physical activity and improve sleep quality during pregnancy.