Publication Type: Conference Paper/Unpublished Manuscript
Abstract: Time-diary data offer a unique look at the passive, moderate, and vigorous components of physical activity that may underlie trends in obesity and health. I focus on disparities between the bottom 25% and top 75% of the income distribution. Nationally representative time-diary data between 1965 and 1999 suggest that income disparities in passive activity during free time have increased while disparities in moderate and vigorous choices have not. The largest passive component by far is television viewing. I evaluate several factors that are part of a multilevel explanation for growing disparities in this important passive activity. First, structural changes in work and the economy have produced increases in free time per day and decreases in the purchasing power available per minute of free time among low-income adults, and these factors account for more of the differences in television viewing in 1999 than in 1965. Second, time spent alone and time spent at home account for more of the income disparities in television watching in 1999 than in 1965. Third, changes in the demographic composition of both the lower 25% and upper 75% income groups account for some of increasing disparities in television viewing (age, education). Finally, changes in the nature of activity choices, represented in the expansion of television content and moderation of viewing costs may have made television a more appealing free time option for low-income adults.