Association Between Exercise And Prolonged Television Viewing Days On Time-use And Physical Activity Energy Expenditure In Older Us Adults

Abstract

PURPOSE. Our goal was to estimate the time-use exchanges associated with exercise, prolonged television viewing, and work days on the amount and type of sedentary and physically active behaviors and physical activity energy expenditure. METHODS. Participants were 1,020 older adults who completed up to 6 detailed previous-day recalls over 12-months that provided a profile of the use of time in sedentary and physically active pursuits. We predicted time-use and physical activity energy expenditure (PAEE) outcomes for 1) days with and without exercise, 2) days with or without prolonged television (2+h/day), and 3) work vs non-work days. To estimate time-use exchanges we used repeated measures and linear mixed models, adjusting for age, sex, season of the year, and day of the week. RESULTS. Exercise days were associated with less sedentary time (-0.37 hrs/d) and light activity (-0.29 hrs/d), and less household, work, and shopping activities. Compared to non-exercise days, the increase in total PAEE on exercise days (2.83 MET-hrs/d) was only about half that expended during exercise (5.98 MET-hrs/d). Prolonged television viewing was associated with an increase in total sedentary time (0.86 hrs/d) and less light (-0.45 hrs/d) and moderate-vigorous intensity activity (-0.41 hrs/d), and thus lower total PAEE (-2.43 MET-hrs/d). Work days were associated with less sleep (-0.91 hrs/d) and an increase in total sedentary time (1.32 hrs/d). DISCUSSION. Exercise was associated with an increase in PAEE, but due to reductions in other activities, only about half of the energy expended during exercise trickled-up to total daily PAEE. Prolonged television viewing was associated less PAEE and less moderate- vigorous activity. These findings provide new insights into possible compensation associated with exercise training, and suggest a strong link between television viewing and physical inactivity.