In line with Caspersen et al., we differentiate general physical activity, which encompasses any bodily movement, from PE. PE is defined as a subset of physical activity that is planned, structured, and repetitive, with the ultimate goal of enhancing or maintaining physical fitness (Caspersen et al., 1985; Dasso, 2019). Sustaining intentional health behaviors like PE requires more than just an awareness of its benefits; it necessitates substantial psychological determination (Duckworth et al., 2007).

College students' participation in PE is influenced by a variety of factors, among which personal psychological traits, especially Grit, play a key role (Messina et al., 2020). To understand why some students maintain regular participation in PE while others do not, it is essential to examine the role of psychological traits such as Grit. Grit, characterized by the sustained passion and perseverance needed to achieve long-term goals (Guelmami et al., 2022), is a fundamental trait in this context. Motivation and social cognitive theory (Schunk and DiBenedetto, 2020) provides a framework for understanding how such traits influence behavior. Within this framework, Grit can be conceptualized as a decisive personal factor that drives an individual's agency and determination, thereby influencing their behavioral choices and their persistence in the face of environmental or self-regulatory challenges in the exercise domain (Gifford and Nilsson, 2014).

As an important psychological resource, grit can directly translate to PE-related behaviors, such as maintaining a consistent workout frequency (e.g., exercising 3-4 times per week), increasing the duration or intensity of sessions over time, and persisting with the exercise regimen despite academic stress or lack of motivation (Liu M. et al., 2024; Longakit et al., 2025). The positive impact of Grit on healthy behaviors is mainly reflected in two aspects: mental health and behavioral participation. On the one hand, individuals with high Grit can maintain an optimistic and open-minded attitude when facing life's stress and setbacks, and are less easily swayed by negative emotions (Hou et al., 2022; Zhou et al., 2025). On the other hand, individuals with high Grit exhibit higher self-discipline and proactivity in adopting healthy behaviors, effectively adhering to habits such as regular exercise and a balanced diet (Totosy De Zepetnek et al., 2021). Drawing from the preceding discussion, the present research puts forward a hypothesis:

The Organic Assessment Process Theory posits that individuals consciously evaluate the potential value of novel stimuli for their growth and self-actualization (Rogers, 1964), thereby influencing their decisions. In simpler terms, this theory suggests that people have an innate drive to grow and improve, and they actively seek out and engage in challenging activities that help them realize their full potential. PGI, which is the conscious and proactive tendency to improve oneself, is closely linked to self-development and behavioral choices (Cai and Lian, 2022; Gong et al., 2022). Those with a high degree of PGI possess an intense aspiration for self-improvement and are adept at identifying their developmental needs, planning actions, and actively implementing them (Feraco et al., 2023; Yue et al., 2025). In the context of physical exercise, for example, a student with high PGI might actively seek out new workout routines, set progressive fitness goals, and proactively schedule gym sessions into their weekly calendar. Research has shown that PGI helps establish healthy lifestyles and promotes comprehensive physical and mental development (Lin et al., 2024; Weigold et al., 2024).

Individuals with Grit, characterized by high goal commitment, are more likely to view regular exercise as a pathway for self-improvement when faced with PE, which promotes physical and mental health (Totosy De Zepetnek et al., 2021). PGI can further motivate these individuals to adjust strategies, overcome obstacles, and persistently achieve their exercise goals. Studies have demonstrated a significant correlation between Grit and PGI, with individuals who are highly gritty being more adept at breaking down long-term goals into phased plans and demonstrating stronger self-development motivation (Xu et al., 2023; Lam and Zhou, 2020; Styk et al., 2019). While this connection has been established primarily in academic and professional settings in Western cultures, we expect this relationship to hold within the Chinese university context, where both perseverance and the drive for self-improvement are highly valued cultural ideals. PGI is also a key driver of positive behavioral change, closely related to the persistence and intensity of PE (Shurtz et al., 2024). Students with high PGI are more likely to persist in their exercise. Thus, PGI complements grit in ensuring long-term adherence; while grit provides the staying power to endure challenges, PGI provides the strategic direction and motivation for continuous improvement, preventing stagnation. Based on this, the current study puts forward a hypothesis:

Bandura's self-efficacy theory posits that an individual's subjective assessment of their capability to complete a specific task, namely SE, significantly influences behavioral choices, the effort invested, and perseverance in the face of challenges, making it a crucial factor for behavioral change and goal attainment (Bandura, 1997). Grit, characterized by persistent dedication and sustained effort toward long-term goals, is closely linked to SE (Meng et al., 2025; De Lorenco-Lima et al., 2025). Individuals with Grit often have high SE, setting challenging goals and taking proactive steps to achieve them (Dale and Yan, 2024; Hwang and Lee, 2024).

The Organic Assessment Process Theory suggests that a clear understanding of one's abilities helps evaluate the potential value of new stimuli, facilitating self-actualization (Maurer and Daukantaite, 2020; Li et al., 2023). For college students, engaging in PE, which enhances both physical and mental wellbeing, requires overcoming challenges such as inertia and effective time management (Snedden et al., 2019; Martín-Rodríguez et al., 2024). Students with high Grit are more likely to view physical activity as a means of self-improvement (Tao et al., 2024a). Their SE affects their confidence in maintaining exercise routines, and an individual's belief in their ability to exercise is crucial for their actual participation. For instance, in structured exercise programs, an individual's self-efficacy can predict whether they will attempt more challenging workouts, adhere to the program when faced with fatigue, and ultimately achieve their fitness goals (Tao et al., 2024b). Several recent studies have consistently demonstrated a positive relationship between grit and self-efficacy (Alhadabi and Karpinski, 2020; Wolters and Hussain, 2015; Özhan, 2021). Based on this, the present study proposes a hypothesis.

According to social cognitive theory, an individual's cognitive factors and behaviors interact with each other, jointly shaping the occurrence and maintenance of behaviors (Bandura, 2001). Specifically, the PGI fuels the belief in one's capability to act SE. PGI reflects an individual's active pursuit of self-development, proactive goal-setting, and implementation of actions, while SE represents an individuals' subjective judgment of their ability to complete specific behaviors (Cai and Lian, 2022). Individuals with high PGI are likely to explore pathways for self-development actively. They set detailed, phased goals and feasible planning strategies, thereby accumulating successful experiences, which are vital sources for enhancing SE. For example, a student high in PGI who decides to improve their health will not only set a goal but will also create a detailed plan (e.g., researching running techniques, creating a weekly training schedule). This proactive planning, combined with the experience of early success in following the plan, directly builds their self-efficacy for the larger goal. Empirical studies have demonstrated a significant positive correlation between PGI and SE (Çankaya et al., 2017). Students' performance in planning, willingness to change, and proactive actions can positively predict their SE in specific tasks (Olckers and Harumavamwe, 2025). Conversely, students with low PGI may fail to transform their perseverance into tangible outcomes, even if they possess determination. This is due to the lack of effective goal-planning and action strategies, resulting in slow SE enhancement and even self-doubt (Jacobs et al., 1984; Cherewick et al., 2023; Sidenko, 2025). This insight suggests that psychological interventions aimed at boosting exercise adherence should not only focus on building self-efficacy directly but should also include components designed to foster a personal growth mindset.

In the context of PE, Grit propels students to set long-term goals. Those with high PGI plan and tackle challenges, accumulating successful experiences that further enhance their SE. This sequential enhancement motivates their continued participation in PE. Therefore, PGI and SE may create a chain-mediation effect on exercise behavior (Meng et al., 2022; Kadier et al., 2025). Based on this, the study proposes a hypothesis (see Figure 1 for a visual representation of the proposed model):

In conclusion, this study focuses on Chinese college students to explore the relationship between Grit and PE. Additionally, the study examines whether PGI and SE mediate the relationship between Grit and PE. As illustrated in Figure 1, the study proposes a hypothetical model to uncover the underlying mechanisms through which Grit influences college students' PE. By exploring this psychological chain, this study not only offers a novel theoretical framework for understanding exercise adherence but also provides a foundation for developing targeted interventions that cultivate grit and its cognitive-motivational correlates to promote lifelong health.

The sample size for this study was determined using GPower 3.1 software and empirical rules for social science research. A power analysis for multiple regression in a chain mediation model indicated a minimum of 193 participants, assuming a medium effect size (f² = 0.15), α = 0.05, and power = 0.80 (Kang, 2021). Given the model's complexity, the number of predictors was set to 5. Empirical rules suggested a sample size of 10 to 15 times the number of questionnaire items (35 items), recommending 350 to 525 participants. Integrating these methods, a minimum sample size of 350 was established (Lakens, 2021). While a minimum sample size of 350 was established, we aimed to collect a substantially larger sample to increase statistical power, minimize sampling error, and enhance the generalizability and robustness of our findings within the Chinese college student population.

Data were collected from 2,559 college students from six colleges in central China between September 7 and November 3, 2024, using the online platform Wenjuanxing (https://www.sojump.com). Of the 2,716 responses collected, 2,559 were valid, yielding a 94.22% response rate. To ensure data quality, several measures were implemented. First, we excluded incomplete questionnaires. Second, we removed participants who took less than 3 min to complete the survey, as this indicated potentially careless or hasty responses.

Additionally, we excluded participants who showed a pattern of regular or repetitive answering, which suggested insincere or non-attentive participation. Third, two attention-check items (e.g., Please select ‘Strongly Agree' for this item) were embedded within the survey. Participants who failed to answer these items correctly were removed from the final dataset. This rigorous screening process helps ensure the reliability and validity of the self-reported data. The sample included 1,262 males (49.3%) and 1,297 females (50.7%), with an average age of 20.42 years (±2.55), and ages ranging from 17 to 25, which is typical for undergraduate students in China. The participants were recruited from six comprehensive universities in central China, which include natural sciences, engineering, arts, liberal arts, and engineering and technology, thereby representing a broad cross-section of the general Chinese college student population. The demographic details are presented in Table 1.

Prior to the primary analyses, to ensure the normality of the data, we excluded data points with absolute skewness greater than 1 and kurtosis greater than 3 by standard statistical practices. In conducting the data analysis, we employed SPSS 26.0. We began by computing descriptive statistics for the demographic variables of age and gender, as well as for the scale scores related to Grit, PGI, SE, and PE. Following this, we utilized Pearson correlations to explore the interrelationships among these variables. The normality of the scale score distributions was evaluated using skewness and kurtosis tests. Subsequently, we carried out mediation analysis with the SPSS PROCESS macro (Model 6) to delve into how PGI and SE mediate the relationship between Grit and PE (Hayes et al., 2017). For estimating indirect effects, we applied the bias-corrected Bootstrap method, utilizing 5000 bootstrap samples. A 95% confidence interval that excluded zero was considered indicative of a significant mediating effect (Cheung and Lau, 2008). Prior to conducting the mediation analysis, all predictor, mediator, and outcome variables were standardized (i.e., converted to Z-scores) to facilitate the interpretation of the path coefficients. In this analysis, gender and family residence were incorporated as covariates.

To assess the potential impact of standard method bias stemming from self-reported data, we employed Harman's single-factor test. The initial factor accounted for 19.74% of the variance, which is considerably lower than the 40% cutoff (Podsakoff et al., 2003). This suggests that common method bias does not pose a substantial concern in this study.

Table 4 presents the fundamental descriptive statistics for Grit, PGI, SE, and PE. The mean scores were 3.376 ± 0.957 for Grit, 3.035 ± 0.681 for PGI, 2.718 ± 0.697 for SE, and 2.940 ± 1.903 for PE. To evaluate the normality of these variables' distributions, skewness and kurtosis tests were performed. With a sample size over 300, variables having skewness below three and kurtosis below eight are deemed approximately normally distributed (Kim, 2013). As indicated in Table 4, the skewness values fall between −0.228 and 0.378, and the kurtosis values are between −0.964 and −0.138, suggesting near-normal distributions. All variables showed significant correlations. Grit correlated positively with PGI (r = 0.410, P < 0.01), SE (r = 0.390, P < 0.01), and PE (r = 0.315, P < 0.01). PGI correlated positively with SE (r = 0.238, P < 0.01) and PE (r = 0.288, P < 0.01). SE also correlated positively with PE (r = 0.345, P < 0.01).

After standardizing the four variables and controlling for gender and family residence, mediation analysis was conducted using Model 6, with the results shown in Table 5. Grit was found to be positively correlated with PGI (β = 0.406, P < 0.001), SE (β = 0.351, P < 0.001), and PE (β = 0.145, P < 0.001). PGI was positively correlated with SE (β = 0.093, P < 0.001) and PE (β = 0.157, P < 0.001). Moreover, SE was positively correlated with PE (β = 0.243, P < 0.001). The tested model diagram is illustrated in Figure 2.

The study utilized Hayes' bias-corrected non-parametric percentile Bootstrap method, employing 5000 bootstrap samples to determine the 95% confidence intervals. Mediating effects were deemed statistically significant if their 95% confidence intervals excluded zero (Hayes et al., 2017). As shown in Table 6, significant mediating effects were identified for PGI (95% CI: [0.047, 0.081], effect size: 0.064), SE (95% CI: [0.070, 0.102], effect size: 0.085), and the chain mediation of PGI and SE (95% CI: [0.005, 0.014], effect size: 0.009). These results confirm that all three pathways significantly mediate the relationship between Grit and college students' PE, thereby validating the study's hypotheses. It is important to note that this method does not report fit indices such as RMSEA (Preacher and Hayes, 2008).

The results of this study indicate a significant positive correlation between Grit and PE among college students, a finding that aligns with prior research and confirms hypothesis 1. This conclusion is similar to previous research findings (Kim, 2020; Messina et al., 2020; Guelmami et al., 2022; Liu et al., 2025).

Individuals with high levels of Grit likely possess the resilience to overcome common barriers to exercise, such as time constraints or fatigue. Additionally, when students set exercise goals that match their skill levels, they experience a sense of accomplishment, which ignites interest, reduces the fear of failure, and strengthens their motivation to continue participating in physical activities (Jacobs et al., 1984; Sidenko, 2025). At the same time, we must consider alternative explanations for this correlation. It is possible that confounding factors, such as pre-existing levels of social support, access to university sports facilities, or even underlying genetic predispositions for activity, could influence both an individual's Grit and their exercise habits. Furthermore, the relationship could be reciprocal, with regular exercise itself helping to build discipline and Grit over time.

Conversely, students lacking Grit often struggle to maintain a positive mindset when confronted with challenges in PE and are more likely to give up when encountering difficulties (Gorin et al., 2024). This behavior not only undermines their self-confidence but also decreases their likelihood of continuing to engage in PE. Therefore, cultivating Grit in college students is crucial for increasing their participation and persistence in PE. By enhancing students' Grit, we can help them maintain a positive attitude when facing difficulties in PE, thereby improving their participation and exercise outcomes. However, it is crucial to acknowledge that our cross-sectional design only establishes an association; it does not permit causal claims. Future longitudinal research is needed to confirm whether cultivating Grit indeed leads to an increase in physical exercise.

This study confirms that college students' Grit not only directly promotes PE but also indirectly influences this behavior through PGI, thereby supporting hypothesis 2. This finding is consistent with the Organic Assessment Process Theory (Maurer and Daukantaite, 2020; Li et al., 2023) and Goal-Setting Theory (Locke and Latham, 2006), offering a new perspective for understanding the PE of college students. The Organic Assessment Process Theory posits that an individual's clear understanding of their own abilities helps them assess the potential value of new stimuli, thereby facilitating self-actualization (Tao et al., 2024a). In the context of PE among college students, this theory underscores the pivotal role of self-awareness in fostering PE. College students with higher levels of Grit typically possess a clearer understanding of their abilities, enabling them to better evaluate the value of PE and regard it as a vital pathway for self-improvement (Liu M. et al., 2024; Longakit et al., 2025). Goal-setting theory further elucidates this process (Locke and Latham, 2019). This theory posits that clear and challenging goals can significantly enhance an individual's motivation and behavioral performance. College students with high Grit are more inclined to set challenging PE goals and translate these goals into concrete actions through PGI (Cai and Lian, 2022; Yue et al., 2025; Weigold et al., 2024). This goal-setting process not only bolsters their intrinsic motivation but also heightens their persistence in the face of difficulties, thereby sustaining their PE. Empirical studies have also confirmed that PGI, as a core driving force for self-improvement and goal achievement, can effectively transform Grit into concrete actions. College students with high PGI are more likely to proactively engage in behaviors that benefit themselves (Lin et al., 2024; Weigold et al., 2024; Çankaya et al., 2017).

Therefore, universities should encourage students' PGI. This can be achieved through concrete applications. For instance, universities could offer workshops focused on developing self-awareness, personal goal-setting, and reflective practices. Another promising approach is curriculum integration, where personal development modules could be embedded within first-year orientation programs or general education courses, guiding students to actively plan their academic, personal, and health-related growth. However, implementing such interventions is not without challenges. Obstacles may include low student engagement due to academic pressures, a lack of trained facilitators, and limited institutional resources. To overcome these hurdles, universities could offer incentives such as course credits or micro-credentials for participation. Leveraging peer mentors trained in PGI principles could offer a scalable and relatable solution, while partnerships with university counseling centers can provide the necessary professional expertise.

The study results confirmed hypothesis 3, that SE acts as an independent mediator between Grit and college students' PE. This aligns with Bandura's Self-Efficacy theory (Bandura, 2001), which posits that individuals' beliefs and cognitive mechanisms significantly influence their behavior and psychological states (Bandura, 1982). As a significant psychological trait, Grit can notably affect college students' SE, which in turn impacts their PE (DuCharme and Brawley, 1995; Zhou and Huo, 2022). This finding is consistent with numerous prior studies, regardless of whether qualitative or quantitative methods were used and whether the samples were from Western or Eastern contexts (Jacobs et al., 1984; Bill et al., 2023; Liu L. et al., 2024; Judge and Bono, 2001; Mesurado et al., 2018). It is important, however, to consider the nuances of measuring self-efficacy. Contextual factors can influence self-reported efficacy.

Prior research has indicated that individuals with high SE tend to employ more positive and effective strategies when confronting challenges (Bill et al., 2023; Yu et al., 2025). As a result, they generally have better experiences within the realm of PE and health. Given the mutually reinforcing relationship between PE and health status, one might wonder whether a similar mechanism and pattern of action exists between college students' SE and health status. To explore this dynamic interplay, future research should move beyond cross-sectional designs. A longitudinal approach, such as a cross-lagged panel model, would be ideal for disentangling the temporal precedence and estimating the strength of the reciprocal effects between SE and health status over an academic year.

Overall, SE plays a crucial role in college students' PE. It is not only a vital mediating mechanism through which Grit influences PE but also a key psychological factor that enables college students to maintain a positive attitude and continue participating in PE. This finding underscores the importance of cultivating SE among college students. In future educational practices, colleges and relevant educational institutions should place great emphasis on fostering college students' SE. By designing and implementing targeted educational interventions, such as offering psychological counseling courses related to PE, organizing a variety of sports competitions, and providing personalized PE guidance, these institutions can help college students develop a proper concept of PE, enhance their SE, and thus promote their active participation in PE. This will improve their physical and mental health and lay a solid foundation for their comprehensive development.

The study results confirmed hypothesis 4, that PGI and SE act as a chain mediator between Grit and PE among college students. This complete pathway, as visualized in our proposed model (see Figure 1). On the one hand, Grit is an important psychological quality in the personal development and growth of college students (Hou et al., 2022). The proactive PGI cultivated and shaped by Grit is crucial for the development of PE in college students. College students with Grit exhibit stronger PGI; they are more willing to actively explore new ways and opportunities for PE and to seek out exercise plans and goals that suit them (Yu et al., 2025; Zhao and Yin, 2024). This proactive attitude enables them to continually try and challenge themselves during PE, thereby gaining more exercise experience and successful experiences (Caspersen et al., 1985). These successful experiences and positive feedback are important sources of SE. Therefore, college students with higher levels of PGI often have higher levels of SE, and vice versa (Weigold et al., 2024).

On the other hand, college students with high PGI receive more attention and recognition during PE. In the campus environment, where sports resources are relatively limited, those with high PGI participate more actively in sports activities, demonstrating their athletic abilities and enthusiasm for PE (Yukhymenko-Lescroart, 2021; Almagro et al., 2020). This active participation and demonstration attract more attention and affirmation, including from peers, coaches, and sports clubs. This attention and affirmation create a psychological advantage that enhances their SE. In summary, Grit, PGI, and SE are key factors influencing the PE of college students.

Although all mediation paths in our study are statistically significant, the chain mediating effect (PGI → SE) accounts for only 3% of the total effect. This small effect size may reflect the complex psychological mechanisms between PGI and SE, which various factors could moderate. Nevertheless, the identification of this chain mediating path holds significant theoretical importance. It reveals the underlying mechanism through which Grit influences physical exercise behavior via PGI and SE, offering a new perspective on how psychological processes mediate the impact of Grit on healthy behaviors. From a practical standpoint, this path underscores the importance of fostering personal growth, initiative, and self-efficacy. By enhancing students' PGI, we can indirectly boost their self-efficacy, thereby promoting physical exercise behavior. This intervention strategy may be particularly effective for students who lack intrinsic motivation. Future research should further explore the relationship between PGI and SE, as well as their roles in different cultural and educational contexts, to gain a more comprehensive understanding of how Grit affects physical exercise behavior.

This study has several limitations that should be acknowledged. First, the assessment of PE was primarily conducted through a single-item self-report measure, without the use of objective assessment tools such as accelerometers or fitness trackers. Although self-reporting is commonly used in research due to its feasibility and cost-effectiveness, it is subject to recall bias and social desirability bias, which may affect the accuracy of participants' reports regarding their PE levels, potentially influencing the study's findings. Second, the relationship between Grit, PGI, SE, and PE is complex and likely influenced by multiple factors, including individual differences, environmental factors, and cultural contexts. However, the cross-sectional design of this study limits the ability to infer causal relationships among these variables. Future studies using longitudinal designs are needed to better elucidate the temporal and causal relationships among Grit, PGI, SE, and PE. Third, the study sample consisted exclusively of college students from central China, which may limit the generalizability of the findings to other populations. Future research should include more diverse cohorts, such as students from different regions, different educational levels, and different cultural backgrounds, to determine whether the observed associations among Grit, PGI, SE, and PE hold across different demographic and cultural contexts. Fourth, this study used a convenience sampling method from six universities in central China, which may cause insufficient representation of students from other regions or types of educational institutions. Future studies are suggested to expand the sampling range to include a broader and more diverse sample of college students, in order to enhance the external validity of the findings.