Premium
Exercise effects on night‐to‐night fluctuations in self‐rated sleep among older adults with sleep complaints
Author(s) -
BUMAN MATTHEW P.,
HEKLER ERIC B.,
BLIWISE DONALD L.,
KING ABBY C.
Publication year - 2011
Publication title -
journal of sleep research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.297
H-Index - 117
eISSN - 1365-2869
pISSN - 0962-1105
DOI - 10.1111/j.1365-2869.2010.00866.x
Subject(s) - sleep (system call) , morning , sleep onset latency , medicine , randomized controlled trial , physical therapy , pittsburgh sleep quality index , sleep onset , psychology , cognition , sleep quality , insomnia , psychiatry , computer science , operating system
Summary Sleep interventions have rarely explored reductions in night‐to‐night fluctuations [i.e. intra‐individual variability (IIV)] in sleep, despite the negative impacts of such fluctuations on affective states and cognitive and physical symptoms. In a community‐based randomized controlled trial we evaluated whether physical exercise reduced IIV in self‐rated sleep outcomes among middle‐aged and older adults with sleep complaints. Under‐active adults 55 years and older ( n = 66, 67% women) with mild to moderate sleep complaints were randomized to 12 months of a moderate‐intensity endurance exercise ( n = 36) or a health education control group ( n = 30). Daily sleep logs, Pittsburgh Sleep Quality Index (PSQI) and in‐home polysomnographic sleep recordings (PSG) were collected at baseline, 6 months and 12 months. Sleep log‐derived means and IIV were computed for sleep‐onset latency (SOL), time in bed, feeling rested in the morning, number of nighttime awakenings, and wake after final awakening (WAFA). Using intent‐to‐treat methods, at 6 months no differences in IIV were observed by group. At 12 months, SOL‐based IIV was reduced in the exercise group compared with the control (difference = 23.11, 95% CI: 3.04–47.18, P = 0.025, Cohen’s d = 0.57). This change occurred without mean‐level or IIV changes in sleep–wake schedules. For all sleep variables, except SOL and WAFA, IIV changes and mean‐level changes in each variable were negatively correlated ( r = −0.312 to −0.691, P < 0.05). Sleep log‐derived IIV changes were modestly correlated with mean‐level PSQI and PSG‐based changes at 12 months. Twelve months of moderate‐intensity exercise reduced night‐to‐night fluctuations in self‐rated time to fall asleep, and this relationship was independent of mean‐level time to fall asleep.