5.4: Correlates of Physical Activity and Sedentary Behavior

Researchers study the correlates of physical activity and sedentary behavior to improve understanding. Studying and exploring what factors are related to these behaviors typically follows a developmental perspective. That is,how do these factors associate with behavior over the lifespan? For example,parental support for physical activity is a positive correlate of physical activity for children and adolescents (Van Der Horst et al., 2007) but would not be as salient to the physical activity of older adults. Studying developmentally appropriate correlates is useful to identify factors beyond what might be specified in a theory, to reevaluate or expand upon existing theories, or to compare the relative strength of associations of many correlates simultaneously. Some of these correlates may be sensitive to intervention or change, such as perceptions of time or outcome expectations. Other correlates may help researchers identify demographic or individual characteristics that may be risk factors for low physical activity or high sedentary behavior.Researchers generally organize these factors into personal, social, or environmental categories.

5.4.1. Personal

Personal-level correlates refer to factors within the individual such as behaviors, perceptions, beliefs, motivations, demographic characteristics, and biological or genetic factors. The association of age with physical activity is inverse (Trost et al., 2002).That is, as individuals become older their physical activity declines. This relationship appears to be different for children where age is positively associated with physical activity then begins to decline around age seven (Farooq et al, 2018). Although this corresponds to the time children enter school, adolescence is widely considered as a period associated with lower physical activity and higher sedentary behavior (Brodersen et al., 2007).

In addition to age-related differences, male sex appears to be consistently positively associated with physical activity across the lifespan (Bauman et al., 2012).Sex and gender differences exist during childhood; however, these differences may obscure subgroups within each sex and gender based on trajectories of physical activity behavior. For instance, when looking at trajectories of physical activity from 7 to 15 years, physical activity appears to decline in all children at a population level, regardless of gender. Despite this decline, there does appear to be a subgroup of boys that remains stable in their physical activity over this developmental period (Farooq et al., 2018). There also appears to be no sedentary behavior differences between boys and girls, but sedentary behavior is positively associated with men in adulthood (Bernaards et al., 2016).

Among psychological correlates, reviews over the past 20 years have analyzed dozens of systematic reviews with upwards of 50 different correlates. Most of this research shows that self-efficacy is a consistent positive correlate of physical activity for children, adolescents, and adults (Bauman et al., 2012; Van Der Horst et al., 2007). Other and less consistent positive correlates of physical activity include intentions to be active for both children and adolescents,whereas perceived competence, outcome expectations, and mastery goal orientations are correlates for adolescents but not children (Sterdt et al., 2014). The evidence for other psychological correlates is mixed depending on the study. For instance, there is mixed support among youth research that viewing physical activity as an enjoyable activity is associated with physical activity behavior (Biddle et al., 2011). Sedentary behavior in adults appears to be positively associated with symptoms of depression, stress, and perceived tiredness,whereas perceived health and benefits of reducing sedentary behavior are negative correlates (O’Donoghue et al., 2016).

Behaviors during childhood and adolescence that are consistently positively associated with physical activity include past physical activity behavior and participation in organized physical activity such as sports (Sterdt et al., 2014). In adults, a history of physical activity participation during adulthood appears to be a consistent behavior correlated with higher physical activity (Bauman et al., 2012) whereas having a sedentary job (i.e., desk jobs) appears to be most strongly associated with sedentary behavior (Bernaards et al., 2016). There exist other behaviors either less consistently or more weakly associated with both physical activity and sedentary behavior that differ among children, adolescents, and adults. These include smoking, snacking on high-calorie foods, and overall physical activity levels.

5.4.2. Social

Social correlates include actual and perceived aspects of relationships with other people such as parents, siblings, peers, coaches/teachers, partners, or group members. Parental encouragement and parental social support are positively associated with physical activity for young people (Biddle et al., 2011). Aspects of sibling relationships for youth appear to also positively correlate with physical activity behavior (see Blazo & Smith, 2017).

Outside of the family context, aspects of peer relationships such as peer acceptance, friendship quality, support, and modeling are associated with physical activity (Smith, 2019). Peers include classmates, friends, and teammates of similar age and developmental status. Friends are especially important social agents in adolescence. In a sample of 372 adolescents, friends social support and friends watching were most strongly correlated with physical activity whereas parental and sibling social support were non-significant correlates(Duncan et al., 2005). Peer relationships may be promising to promote physical activity,however,peers can also undermine physical activity (Smith, 2019). Poor relationships with peers signal that a person is not wanted, disliked, or devalued by others. This can appear as conflict, rejection, exclusion, teasing, or bullying. These experiences are typically unpleasant and can have serious lifelong consequences. For example, Ladwig and colleagues (2018) found that negative memories and experiences (e.g., being chosen last for teams) during childhood physical education were negatively associated with attitudes and intentions about physical activity in adulthood.

Other important social relationships correlated with physical activity include coaches, trainers, partners, and group members. For adults, receiving social support from partners, family members, friends, or a physician appears to be positively correlated with physical activity (Kelly et al., 2016). For older adults, social support remains an important correlate of physical activity and can counteract the effects of loneliness. Social support is positively correlated whereas loneliness is negatively correlated with physical activity among older adults (Lindsay Smith et al., 2017). Along with social support, being physically active in groups that emphasized group cohesion and group-dynamics was more effective at getting participants to adhere to exercise interventions than exercising alone (Burke et al., 2006). Engaging in physical activity with others offers opportunities for socialization that helps fulfill an individual’s need to belong. Although it should be noted that not all people may prefer engaging in group-based physical activity. This is particularly relevant for older adults who report preferring group-based physical activity with others similar in age (Beauchamp et al., 2007).

5.4.3. Environmental

The environmental correlates of physical activity and sedentary behavior are characterized by aspects of the context and location.Bauman and colleagues(2012) reviewed correlates of physical activity from an ecological perspective. Walkability, access or proximity to recreation facilities,and other characteristics of the built-environment are among the most consistent correlates related to physical activity for children, whereas land-use mix and residential density are most consistent for adolescents. For adults, walkability and location of recreational facilities were consistent correlates of physical activity with no clear environmental correlates found for older adults. This review demonstrated that characteristics of the environment such as walkability and access to facilities are associated with physical activity behavior. This can have important implications for the development and location of new facilities to promote physical activity behavior.

Another aspect of the environment that can influence physical activity and sedentary behavior is weather. Zheng and colleagues (2021) found that rain is negatively associated with physical activity and positively associated with sedentary behavior,whereas temperature shows the opposite relationship (i.e., positive association with physical activity, negative association with sedentary behavior). Additionally, physical activity appears to vary with changes in seasons such that colder seasons(e.g., winter) are associated with lower physical activity and warmer seasons (e.g., spring and summer) are associated with higher physical activity (Tucker & Gilliland, 2007). These findings may apply to locations that experience weather variation in all four seasons, whereas extreme climates with high humidity and temperatures may show different associations with physical activity and sedentary behavior.

5.4.4. Considerations for Studying Correlates

Studying the factors associated with physical activity and sedentary behavior will benefit from moving beyond cross-sectional research designs (i.e., one point in time) to studying how the association changes over time. This noted, longitudinal designs are more resource demanding than cross-sectional designs,presenting challenges to researchers. Such longitudinal designs can help demonstrate a richer understanding of how associations change or remain stable over time. A twelve-week exercise program provides an illustrative example. In this program, self-efficacy may be the strongest predictor of physical activity in week 1. The strength of self-efficacy may lessen over time and be replaced by social support by week 6. A researcher may find that self-efficacy was most important for initiating the program and as participants affiliated over the course of the program social support became most salient. Thus, such a longitudinal design may offer practical implications for how fitness instructors should structure exercise programs and what to emphasize among participants over time.