Walk to a better night of sleep: testing the relationship between physical activity and sleep.

OBJECTIVES

Many do not sleep well, particularly middle-aged and older adults. Physical activity (PA) shows promise for improving sleep; however, populations with clinical sleep disturbances have been a research focus. It remains unclear whether low-impact daily PA, like walking, can affect sleep in healthy adults.

DESIGN

The current study was embedded within a 4-week randomized controlled trial to increase PA.

SETTING

Participants from the greater Boston area were recruited to participate in a 4-week walking intervention on a rolling basis between October 2015 and August 2016.

PARTICIPANTS

Fifty-nine participants (72% female) were enrolled in the study, with an average age of 49.43 (±8.40) years.

INTERVENTION

The 4-week intervention was aimed at increasing participants' daily steps as the primary outcome. The current, supplementary study examined relationships between monthly and daily PA and sleep.

MEASUREMENTS

Steps and active minutes were measured daily using a Fitbit Zip. Self-reports of sleep quality and duration were assessed daily, along with before and after the intervention.

RESULTS AND CONCLUSIONS

Averaged across the month, daily active minutes were positively related to sleep quality but not duration. Sex moderated this relationship; women who took more steps and were more active reported sleeping better than those less active. Within persons, on days that participants were more active than average, they reported better sleep quality and duration in both sexes. Results suggest that low-impact PA is positively related to sleep, more so in women than men. Findings also showed that PA plays a greater role in predicting sleep quality than duration.