Longitudinal trajectories of physical activity in women using latent class growth analysis: The WIN Study

Abstract

PurposeThis study aimed (1) to examine the longitudinal trajectories in objectively measured physical activity (PA); (2) to identify unknown (i.e., latent) subgroups with distinct trajectories; and (3) to examine the correlates of latent subgroups among community dwelling women.MethodsThe study sample included a total of 669 women from the Women's Injury Study, a 5-year prospective cohort study conducted from 2007 in the Southwest Central region of the US. Pedometer-based step-count data across 18 consecutive months were fitted to a latent growth model (LGM) and a latent class growth model (LCGM). Baseline characteristics were regressed on latent class membership.ResultsThe longitudinal change in PA was best fit to a piecewise LGM with seasonal transitions. Significantly increased and decreased levels of PA were observed during the spring, fall, and winter, respectively (p < 0.001). Three latent subgroups with distinct PA trajectories were identified (low-active (46.8%), somewhat-active (41.3%), and active (11.9%)). Age and body fat percentage at the baseline significantly explained the likelihoods of being in low-active subgroup.ConclusionSeasonal variations in PA among women were observed but may not be practically significant. A relatively large portion of the sample showed low levels of PA for long periods. Intervention strategies should be considered for women who are overweight or obese, and aged >40 years old to promote PA during the life course.

Distinct trajectories of physical activity and related factors during the life course in the general population: a systematic review

“…Objectively measured PA was available from three different research data and was used in six studies [24–29] while the others used self-reported or parent-reported measures of PA [30–45], exercise [46, 47] and SP [23, 26, 28, 48, 49] (Additional file 3: Table S3). The broader term PA trajectories is used to refer to all the different trajectories of PA, exercise and SP.…”

“…The number of PA trajectory classes identified in each study ranged from one to five, and was most commonly either four [23, 24, 26–28, 31, 36, 37, 39–41, 46] or three [24–26, 28, 29, 33–35, 42–45, 48, 49] (Additional file 3: Table S3). Eight studies identified separate trajectories for males and females [24, 25, 38, 43, 44, 46, 48, 49], twelve studied males and females together in the same trajectories [23, 26–28, 30–32, 36, 40–42, 45], five studied females only [29, 35, 37, 39, 47], and two studied males only [33, 34].…”

“…The middle group comprised 8 studies [29, 32, 40–45] (Additional file 3: Table 3). Participant age at baseline ranged from 9 to 90.…”

“…Participant age at baseline ranged from 9 to 90. Two studies using the same data identified trajectories from childhood to adulthood [32, 42], another two, using different data, identified trajectories from adolescence to adulthood [43, 44], one studied adults only [45], and the other three studied adults and older adults [29, 40, 41]. Follow-up time varied from two to 34 years (mean = 19.8 years; median = 23.5 years), and sample size from 497 to 3564 participants.…”

“…Altogether 28 different middle group PA trajectories were reported in the studies (Additional file 4). In most studies, the largest proportions (range 43–86%) of individuals were in the trajectory classes describing either persistent PA [42–44], inactivity [40] or low PA [29, 32, 45] (Additional file 4: c, d, g). Stable PA trajectories (22 trajectories) were more prevalent than change (i.e., a decrease or increase in PA level) trajectories (6 trajectories) (Additional file 4).…”