Abstract
Purpose in life is associated with greater engagement in physical activity. The present research (N = 3473) addresses whether motivations and barriers to physical activity mediate this relation concurrently and prospectively early in the coronavirus pandemic. Higher purpose was associated with greater intrinsic, identified, and external motivation for physical activity and fewer barriers. Intrinsic motivation was a robust mediator of the relation between purpose and more physical activity and less sedentary behavior reported concurrently and prospectively; identified motivation mediated the relation with physical activity. Purpose in life is associated with being more physically active through both greater enjoyment and valuing its benefits.
A sense of purpose in life is the feeling that one’s life is goal-oriented and has direction (Ryff, 1989). It is one of the core components of eudaimonic well-being (Ryan and Deci, 2001; Ryff, 2014) and helps support better mental health (Wood and Joseph, 2010). There is now considerable evidence that sense of purpose also promotes better physical health (McKnight and Kashdan, 2009). Individuals who feel their life is purposeful, for example, have fewer chronic diseases (Boyle et al., 2009), lower risk of dementia in older adulthood (Sutin et al., 2018), and lower risk of premature mortality (Cohen et al., 2016). There are a number of theoretical reasons why a sense of purpose is thought to promote healthier outcomes across the lifespan. In particular, a greater sense of purpose is conceptualized as an organizing framework that helps to structure one’s long-term goals (McKnight and Kashdan, 2009). Individuals with a greater sense of purpose tend to have both greater goal engagement (Irving et al., 2017) and resilience to stress (Ong and Patterson, 2016), which in turn support better health. Further, a sense of purpose helps to guide individuals to select proximal goals that are consistent with long-term strivings and promotes coping strategies that help buffer against stress (McKnight and Kashdan, 2009). This process may provide a cumulative advantage for health with aging (Irving et al., 2017; McKnight and Kashdan, 2009; Windsor et al., 2015).
One reason that purpose in life is associated with better health outcomes is that it is also associated with a healthier lifestyle, including many modifiable behaviors (Kim et al., 2020). One such modifiable factor is physical activity. A number of studies have found that higher purpose is associated consistently with greater engagement in physical activity (Hill et al., 2019; Holahan et al., 2008, 2011; Kim et al., 2020). Most of this literature is based on self-reported physical activity, but higher purpose has also been associated with greater engagement in moderate-to-vigorous physical activity as assessed objectively by accelerometer, as well as by self-report (Hooker and Masters, 2016). In addition to physical activity, there is also evidence that individuals higher in purpose in life also spend fewer hours per day in sedentary behavior (de Oliveira et al., 2021).
Compared to research on the basic association between purpose and physical activity, less work has addressed the mechanisms through which purpose is associated with greater physical activity. Research on a related construct—meaning in life—has found that self-efficacy mediates the relation between meaning and physical activity (Rush et al., 2021): Individuals who view life as more meaningful have greater beliefs in their ability to be active, which accounts for the relation with physical activity. There are many other reasons why an individual may or may not engage in physical activity, and previous studies have speculated on why individuals with more purpose engage in more physical activity. Individuals higher in purpose may engage in more physical activity, for example, because they are intrinsically motivated to engage in such behavior and because they value the benefits of being active (Holahan et al., 2011; Hooker and Masters, 2016; Steptoe and Fancourt, 2019).
These potential mechanisms match well with motivational components of Self-Determination Theory (Ryan and Deci, 2000), which have been implicated explicitly in physical activity (Hagger and Chatzisarantis, 2008). Individuals who have intrinsic motivation engage in physical activity because they enjoy it, individuals who have identified motivation engage in physical activity because they value the benefits of it, individuals who have external motivation engage in physical activity because other people expect them to and out of concern for how they look to others, and individuals with introjected motivation engage in physical activity to reduce the negative feelings of not engaging in it. Intrinsic and identified motivation are associated with being more physically active, whereas external motivation is associated with less physical activity, and results are mixed for introjected motivation (Teixeira et al., 2012). In addition to motivation, perceived barriers to physical activity are also associated with engagement in physical activity. Not surprisingly, individuals who perceive more barriers to physical activity are less likely to engage in it (Müller et al., 2019).
There are a number of theoretical reasons why sense of purpose would be associated with these motivational orientations. Purpose in life is an inner psychological resource that motivates individuals to strive for long-term goals (McKnight and Kashdan, 2009; Musich et al., 2018). Intrinsic motivation is inherently intertwined with how purpose in life is defined as an overarching drive to achieve one’s important goals in life. Individuals are more likely to maintain their goal strivings if they derive internal pleasure from the striving (intrinsic motivation) and value the outcome of the goal (identified motivation), whereas goal strivings that are motivated by obligation (external motivation) or feelings of guilt if not strived for (introjected motivation) are less likely to be maintained over time (Ryan and Deci, 2017). As such, given that purpose is defined in part by a drive to achieve long-term goals, individuals who have a greater sense of purpose may be more motivated by intrinsic and identified motivation than by external and introjected motivation. In addition, individuals often encounter barriers when striving for long-term goals. Presumably individuals high in sense of purpose work through these barriers to be successful in their strivings because of greater engagement and long-term nature of their strivings. We examine these associations within the specific context of physical activity. That is, there is consistent evidence that individuals higher in sense of purpose engage in more physical activity (Hill et al., 2019; Holahan et al., 2008, 2011; Hooker and Masters, 2016; Kim et al., 2020), which suggests a commitment to a physically active lifestyle. This commitment may be facilitated by motivation, and such factors may be one pathway through which purpose in life is associated with greater engagement in physical activity and less time spent in sedentary behavior.
The present research seeks to merge these two literatures by testing the relation between purpose in life and motivations and barriers for physical activity that have been thought to explain the relation between purpose and physical activity. We expect that higher purpose will be associated with more intrinsic and identified motivation, less external and introjected motivation, and fewer barriers to physical activity. We further examine whether these motives/barriers mediate the relation between purpose and physical activity and sedentary behavior reported concurrently and physical activity and sedentary behavior reported during the early days of the coronavirus pandemic in the United States, about 6 weeks after the initial assessment of purpose and motives/barriers. The coronavirus pandemic disrupted just about every aspect of life, especially early in the pandemic, when the world had to adjust to its threats. And, in fact, there were significant declines in average step counts early in the pandemic (Tison et al., 2020). Still, even with the stress of the pandemic, engaging in physical activity is associated with greater well-being (Lesser and Nienhuis, 2020), which suggests that physical activity may help to buffer against the mental health effects of the pandemic. We address the association between purpose in life and physical activity just prior to and during the early days of the pandemic.
Method
Participants and procedure
Participants were from a large internet study of adults who ranged in age from 18 to 100. Participation was open to adults living anywhere in the United States, and participation was roughly proportional to state population size (i.e. there were more participants from larger states than smaller states). The original study was conceptualized as a cross-sectional study of the relation between psychological factors and health. The sample was stratified to have roughly similar number of participants (~500) across seven age bands: 18–19, 20–29, 30–39, 40–49, 50–69, 60–69, and 70+ and to be about 50% male/female gender identity and about 20% African American. Participants were recruited through Dynata (dynata.com) and directed to a Qualtrics survey administered by the Florida State University College of Medicine. Participants were compensated directly through Dynata. Data collection took place between January 31 and February 10, 2020. A total of 3473 participants had valid data on purpose, motivation, barriers, and physical activity.
When the coronavirus pandemic hit the United States, the study was reconceptualized as longitudinal, and participants were recontacted through Dynata to complete another survey. Data collection took place between March 18 and 29, 2020. A total of 2018 participants (n = 1612 for sedentary behavior due to missing data) had valid data and reported on their engagement in physical activity within the last week (see below).
Participants who did not have follow-up data were younger (d = 0.91, p < 0.01), more likely to be female (χ2 = 58.44, p < 0.01), more likely to be African American (χ2 = 33.38, p < 0.01), and had less education (d = 0.34, p < 0.01). Controlling for these sociodemographic differences, there were no differences in purpose, motivation, barriers, physical activity, or sedentary behavior at baseline between participants who did not have follow-up data versus participants who did have follow-up data. The analyses of these data were not preregistered. Data will be made available upon publication and was submitted with this manuscript to the Journal.
Measures
Purpose in life
Participants completed the 7-item version of the Purpose in Life subscale from the Ryff Measures of Psychological Well-being (Ryff, 1989). Items (e.g. “I have a sense of direction and purpose in my life.”) were rated on a scale from 1 (strongly disagree) to 5 (strongly agree). Items were reverse scored in the direction of greater purpose when necessary and the mean taken across items (alpha = 0.77).
Motivation for physical activity
Four motives for exercise were assessed with the Motivation for Exercising/Working Out Questionnaire (https://selfdeterminationtheory.org/). Each motive was measured with three items: Intrinsic Motivation (e.g. “I exercise/work out because I simply enjoy working out.” alpha = 0.84), External Regulation (e.g. “I exercise/work out because others like me better when I am in shape.” alpha = 0.78), Introjected Regulation (e.g. “I exercise/work out because I would feel bad about myself if I didn’t do it.” alpha = 0.66) and Identified Regulation (e.g. “I exercise/work out because I have a strong value for being active and healthy.” alpha = 0.80). Each item was rated on a scale from 1 (strongly disagree) to 5 (strongly agree) and the mean taken in the direction of the motive label.
Perceived barriers to physical activity
Participants completed the 9-item Perceived Barriers to Physical Activity scale (Dishman et al., 2010). Specifically, participants were asked, “How often do these things keep you from being physically active?” Example items are “The weather is bad.” and “I don’t like to sweat.” Items were rated on scale from 1 (never) to 5 (often) and the mean taken in the direction of greater barriers (alpha = 0.90).
Physical activity and sedentary behavior
In the baseline survey, participants were asked about the general frequency of their engagement in moderate (“How often do you take part in sports or activities that are moderately energetic such as, gardening, cleaning the car, walking at a moderate pace, dancing, floor, or stretching exercises?”) and vigorous (“How often do you take part in sports or activities that are vigorous, such as running or jogging, swimming, cycling, aerobics or gym workout, tennis, or digging with a spade or shovel?”) activities. These items were taken from the Health and Retirement Study (Sonnega et al., 2014) and rated on a scale with the response options 1 (hardly ever or never), 2 (1–3 times per month), 3 (once a week), 4 (2–3 times per week), 5 (4–6 times per week), and 6 (every day). The mean was taken across the two items. Participants were also asked about their frequency of sedentary behavior and to report, in hours, the average time they spent sitting per day (not including time spent sleeping). In the follow-up survey on the coronavirus, participants were asked the same questions on physical activity and sedentary behavior, but the timeframe was the frequency specifically within the last 7 days. The physical activity items were rated on a scale that had the response options 1 (none), 2 (1–2 days), 3 (3–4 days), 4 (5–6 days), and 5 (everyday). Sedentary behavior was reported in average hours per day.
Sociodemographic covariates
The sociodemographic covariates were reported age in years, gender identity (male vs female/transgender/other; the latter two options were separate options that were combined with female), race (African American vs other), and education reported on a scale from 1 (less than high school) to 7 (PhD or equivalent).
Statistical approach
Linear regression was used to examine the association between purpose in life and the motivations and barriers for physical activity, controlling for age, gender, race, and education. We then tested the association between purpose and physical activity and sedentary behavior, measured both concurrently and prospectively during the pandemic, controlling for the sociodemographic covariates, with the PROCESS macro (Hayes, 2018). Within this analysis, we also tested a multiple mediator model in which the motives and barriers were evaluated as one pathway through which purpose is associated with physical activity and sedentary behavior, reported both concurrently and prospectively. Note that the estimates in the mediation analysis were standardized, so the results can be interpreted as standard effect sizes.
Data sharing statement
The current article includes the complete raw data-set collected in the study including the participants’ data set, syntax file, and log files for analysis. Pending acceptance for publication, all of the data files will be automatically uploaded to the Figshare repository.
Results
Descriptive statistics for all study variables are shown in Table 1. Correlations among all study variables are in Supplemental Table S1. Table 2 shows the association between purpose in life and motivation and barriers for physical activity. As expected, greater purpose was associated with more intrinsic and identified motivation and with fewer barriers to being active: Participants with more purpose reported that they had more intrinsic motivation to engage in physical activity, valued it more than participants with less purpose, and perceived fewer barriers to engaging in it. Unexpectedly, instead of the expected negative associations, purpose was associated positively with external motivation and was unrelated to introjected motivation. To give context for effect size, Cohen’s d was calculated for each of these factors by the top and bottom quartile of purpose in life, controlling for the covariates: d = 0.50 for intrinsic motivation, d = 0.16 for extrinsic motivation, d = 0.76 for identified motivation, d = 0.07 for introjected motivation, and d = 1.09 for perceived barriers to physical activity. These values indicated a small-to-large effect size for purpose and motivation/barriers.
Descriptive statistics for all study variables.
Note. N = 3473. The ns are lower for the COVID follow-up assessment because of attrition. Education is reported on a scale from 1 (less than high school) to 7 (PhD or equivalent). Purpose in life and motivation are on a scale from 1 (strongly disagree) to 5 (strongly agree). Barriers is on a scale from 1 (never) to 5 (often). Physical activity is on a scale from 1 (hardly ever or never) to 6 (every day). Physical activity COVID follow-up is on a scale from 1 (none) to 5 (everyday).
Associations between purpose in life and motivation and barriers for physical activity.
Note. N = 3473. CI=confidence interval. Males are the reference group for gender (0 = males, 1 = female) and not Black is the reference group for race (0 = not Black, 1 = Black); age, education, and purpose are entered as continuous variables.
Table 3 shows the association between purpose in life and physical activity and sedentary behavior measured concurrently and approximately 6 weeks later. Measured concurrently, purpose in life was associated with more engagement in physical activity (d = 0.49) and with less time spent sitting on average per day (d = 0.30). Purpose was also a prospective predictor of greater physical activity (d = 0.11) and less sedentary behavior (d = 0.10) during the early days of the coronavirus pandemic. Table 3 also shows the results of the mediation analysis. When measured concurrently, intrinsic, external, and identified motivation and perceived barriers mediated the relation between purpose and physical activity. The direct association between purpose and physical activity was reduced but remained significant (the mediators accounted for approximately 70% of the association). For sedentary behavior, only intrinsic motivation was a significant mediator, and, again, accounted for only part of the association (the mediators accounted for approximately 21% of the association). Prospectively, intrinsic motivation and identified motivation mediated the relation between purpose and greater engagement in physical activity. Finally, intrinsic motivation mediated the relation between purpose and less sedentary behavior. In the prospective analyses, motivation accounted for the association between purpose and the two outcomes.
Indirect effects of purpose in life on physical activity/sedentary behavior through motivation and barriers.
Note. N = 3473 for concurrent PA and SB; n = 2018 for Prospective PA; n = 1612 for Prospective SB.
Coefficients are standardized coefficients from the mediation analysis controlling for age, gender, race, and education.
Numbers in parentheses are standard errors.
PA: physical activity; SB: sedentary behavior.
p < .05, **p < .01.
Discussion
The present research supports the literature on purpose and engagement in physical activity and suggests psychological pathways through which this association occurs. Specifically, purpose was associated with motivation to engage in physical activity and with perceiving fewer barriers to being active. Greater enjoyment of physical activity was the most robust mediator: Higher purpose in life was associated with more engagement in physical activity and less sedentary behavior measured both as general frequency and specifically during a 7-day period during a significant public health crisis because individuals higher in purpose inherently enjoy being physically active. Individuals higher in purpose in life also valued physical activity more and, surprisingly, were also motivated to engage in it because of external pressures. This research contributes to process-oriented models of purpose in life that help explain how purpose leads to beneficial behaviors that promote better health outcomes associated with it.
There is a growing literature that links purpose in life to a more active and less sedentary lifestyle. Specifically, purpose has been associated consistently with more engagement in physical activity (Hill et al., 2019; Holahan et al., 2008, 2011; Kim et al., 2020), and there is some evidence that it is associated with less sedentary behavior (de Oliveira et al., 2021). It has been argued that there is something inherently engaging about having a greater sense of purpose in one’s life (Hooker and Masters, 2016). That is, purpose is defined as having a goal-oriented and driven life and presumably there needs to be some level of energy and activity to accomplish one’s goals (Hooker and Masters, 2016).
The present work sought to identify underlying motivations and barriers associated with purpose that may be pathways through which it contributes to a more physically active lifestyle. Using constructs from Self-Determination Theory (Ryan and Deci, 2000), as applied to physical activity (Hagger and Chatzisarantis, 2008; Teixeira et al., 2012), we found support for the relation between purpose in life and greater intrinsic and identified motivation for physical activity. The relation between purpose and the other two motives was surprising. We had expected that individuals high in purpose would not rely on external pressures to be active. The association between purpose and external regulation, however, was positive. Although individuals higher in purpose are motivated by their own internal drive, there is a part of purpose that is a connection with other people (Steptoe and Fancourt, 2019). This connection with others perhaps involves feelings of being responsible to others, a responsibility that includes being physically fit. Individuals higher in purpose may also be more receptive to other people’s advice about physical activity and integrate this information or put pressure on aspects that could help achieving their life goals. Of note, however, it was only a modest mediator of the association with concurrent physical activity and not the other outcomes. This pattern suggests that although individuals high in purpose may have some external motivation to be physically fit, it is not a strong pathway. The null association with introjected motivation was also surprising and indicates that individuals high in purpose may or may not feel motivated to avoid the negative aspects of lack of physical activity.
Intrinsic motivation was the most consistent mediator of purpose and all of the activity-related outcomes. Intrinsic motivation is well-known for its association with behavior: Individuals who enjoy an activity are more likely to engage in it (Ryan and Deci, 2017). There is plenty of evidence that this association applies to physical activity (Rhodes et al., 2009; Teixeira et al., 2012). The present research adds that individuals with more purpose tend to enjoy being physically active, which is one robust pathway that explains the greater physical activity and less sedentary behavior associated with purpose. Interestingly, finding value in physical activity was a consistent mediator between purpose and more physical activity but not sedentary behavior. This pattern suggests that the pathways to less sedentary behavior do not necessarily mirror the pathway to greater physical activity.
There may be a number of other pathways through which purpose is associated with greater engagement in physical activity. Purpose in life, for example is associated consistently with better physical health (Czekierda et al., 2017; Kim et al., 2017). It may thus be that individuals with more purpose are more physically active, in part, because they are healthy enough to be active. Individuals who have more purpose also tend to be conscientious (Ko et al., 2016). Higher conscientiousness may help the individual to plan time to engage in physical activity and thus be more likely to do it. In addition, the literature on a related construct, meaning in life, has found that self-efficacy mediates the association with physical activity (Rush et al., 2021). Like meaning, individuals higher in purpose may engage in more physical activity both because they enjoy it (intrinsic motivation) and because they feel they have the ability to do so (self-efficacy). Given that the motives and barriers did not account for all of the cross-sectional associations between purpose and physical activity and sedentary behaviors, it would be worthwhile to identify and test empirically other mediators in this pathway.
It is of note that purpose was a prospective predictor of more physical activity and less sedentary behavior during a major international health crisis. Participants were asked about their behavior during the White House’s 15 Days to Slow the Spread, which included the recommendation to stay at home (White House, 2020) and many businesses (including gyms) were closed during this period. As such, the pandemic, particularly early on, could be seen as a significant barrier to physical activity. The effect on this behavior in general, however, seems to be mixed: physical activity and sedentary behavior appear to have both increased in the early days of the pandemic (Stephan et al., 2020). The present results suggest that even in the acute phase of a public health crisis that interfered with most aspects of life, individuals higher in purpose remained more physically active and less sedentary than those with a lower sense of purpose.
There is a growing literature that implicates purpose in better health outcomes, from better management of diabetes (Hafez et al., 2018) to lower chronic disease burden (Boyle et al., 2009) to lower risk of dementia (Sutin et al., 2018) and premature mortality (Cohen et al., 2016) in older adulthood. Of note, physical activity is also implicated in these health outcomes (Reiner et al., 2013). The present research thus shows the psychological underpinnings of how purpose contributes to a behavior that is a major contributor to numerous health outcomes. One next critical question is whether interventions to increase purpose also help increase engagement in physical activity. There is replicable evidence that purpose is malleable and can be increased through intervention (Park et al., 2019). Whether such an increase in purpose leads to downstream durable changes in behavior, such as physical activity, is not yet known.
The present research had several strengths, including a large sample that covered the adult lifespan, multiple motives for physical activity, and physical activity reported before and during a specific time when the whole country was experiencing a collective stressor. There are also some limitations to consider. First, physical activity was self-reported. Although a limitation, previous research has found similar associations between purpose and physical activity measured with an accelerometer, as well as self-report (Hooker and Masters, 2016). Second, we did not address the potential bidirectional associations between purpose and physical activity. There is some evidence that interventions to increase physical activity also increase purpose in life (Delextrat et al., 2016). Multiple assessment of both purpose in life and physical activity are needed to address potential bidirectional associations and whether motivation mediates changes in physical activity over time. Third, we did not measure other potential psychological mediators that have also been implicated in the relation between constructs related to purpose and physical activity (e.g. self-efficacy; Rush et al., 2021). Future work could take a more comprehensive approach. In addition, the follow-up was designed to be brief to capture behavioral responses to the early days of the pandemic, but the follow-up period was short for a longitudinal study. Attrition was high due to the change in study design (i.e. the original study was meant to be cross-sectional). Despite the attrition, the pattern of association was similar across the cross-sectional and prospective analyses. Finally, although the sample was stratified and recruited from across the United States, it is unlikely to be representative of the population of the United States or other populations. Future research should address these associations in more diverse populations to evaluate generalizability.
Despite these limitations, the present research adds to a process-oriented model of purpose and physical activity. Specifically, purpose in life is associated with a beneficial profile of motivation and barriers for physical activity, and this profile explains, in part, how purpose is associated with greater engagement in physical activity.
Supplemental Material
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Research Data
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Supplemental material, sj-sps-3-hpq-10.1177_13591053211021661 for Sense of purpose in life and motivation, barriers, and engagement in physical activity and sedentary behavior: Test of a mediational model by Angelina R Sutin, Martina Luchetti, Yannick Stephan and Antonio Terracciano in Journal of Health Psychology
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sj-sps-4-hpq-10.1177_13591053211021661 – Supplemental material for Sense of purpose in life and motivation, barriers, and engagement in physical activity and sedentary behavior: Test of a mediational model
Supplemental material, sj-sps-4-hpq-10.1177_13591053211021661 for Sense of purpose in life and motivation, barriers, and engagement in physical activity and sedentary behavior: Test of a mediational model by Angelina R Sutin, Martina Luchetti, Yannick Stephan and Antonio Terracciano in Journal of Health Psychology
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sj-spv-5-hpq-10.1177_13591053211021661 – Supplemental material for Sense of purpose in life and motivation, barriers, and engagement in physical activity and sedentary behavior: Test of a mediational model
Supplemental material, sj-spv-5-hpq-10.1177_13591053211021661 for Sense of purpose in life and motivation, barriers, and engagement in physical activity and sedentary behavior: Test of a mediational model by Angelina R Sutin, Martina Luchetti, Yannick Stephan and Antonio Terracciano in Journal of Health Psychology
Footnotes
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Research reported in this publication was supported by the National Institute on Aging of the National Institutes of Health under Award Numbers R01AG053297 and R01AG068093. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
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References
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