Measuring the way people vary across time in meeting recommended levels of physical activity is a prerequisite to quantifying exposure in outcome studies or identifying determinants of sufficient physical activity. The study determined whether distinct patterns of change in sufficient physical activity could be identified in a population.
A cohort (N = 497) from a random, multiethnic sample of adults living in Hawaii was assessed every 6 months for 2 years beginning spring 2004. Latent transition analysis classified people as sufficiently or insufficiently active each time.
In the total cohort, odds that people would move from insufficient to sufficient activity (45% to 59%) at each 6-month transition were higher than odds they would move from sufficient to insufficient activity (8% to 13%). However, those odds, as well as types and amounts of physical activity, differed widely among and within 3 of 4 transition classes that represented 21% of the cohort.
Point-prevalence of sufficient physical activity in the total cohort was similar to contemporary U.S. estimates. However, physical activity varied between and within subgroups of the cohort. Further research is needed using self-report and objective measures to determine patterns of change in sufficient physical activity in other representative cohorts.