The research on psychosocial factors associated with the consumption of prohibited performance-enhancing substances (PES) in sports, physical activity, and fitness has increased over the past 20 years (e.g., Wiefferink et al., 2008; Morente-Sánchez and Zabala, 2013; Ntoumanis et al., 2014; Tavares et al., 2019a). Researchers’ interest in this area may be attributed to the prevalence rates of prohibited substance [e.g., anabolic-androgenic steroids (AAS), stimulants, erythropoietin (EPO), human growth hormone, and diuretics] use, which was shown to be as high as 73% in competitive sports (Gleaves et al., 2021), and 70% in the fitness context (Tavares et al., 2019a). Moreover, the media impact of cases involving performance-enhancing substance use in major global sports competitions, such as the Olympic Games (Associated Press/NBC, 2022) or the FIFA World Cup (Bubel, 2023), further contributes to the attention this topic has received.

While specific regulations and a publication of a list of prohibited substances by the World Anti-Doping Agency (WADA) exist for professional sports contexts to inform and control behavior associated with PES use, only a few countries have legal procedures for controlling fitness participants’ substance use (Thualagant, 2012). This fact should be a concern for these substances have long-term physical and psychological consequences on individuals’ health (Pope et al., 2014). To address this concern, this article will focus on the identification of the profile of gym-goers who do not engage in this risky behavior.

Researchers have been trying to understand and evaluate the psychological determinants of PES use by fitness participants (Elbe and Barkoukis, 2017). Studies have focused on attaining knowledge of predisposing factors influencing the decision to consume PES to influence consumption behavior and prevent such acts (Petróczi and Aidman, 2008). This is evident in the multitude of variables analyzed to assess determinants associated with PES use in fitness, such as participants’ attitudes and judgments, beliefs about the outcomes or consequences, and social influences on engaging in PES use (e.g., Allahverdipour et al., 2012; Tavares et al., 2020a).

Although scientific evidence identifies a set of psychological and social determinants associated with PES use, including intentions, attitudes, and beliefs (e.g., Wiefferink et al., 2008; Tavares et al., 2020a), it is important to examine the reasons for non-use, that is, to identify the characteristics of those gym-goers who do not use PES. The identification of the profile of these individuals will help distinguish risk characteristics prone for PES use from preventive ones. Emphasizing the promotion of the latter factors rather than focusing on penalizing the use of PES by gym-goers might be an alternative strategy to promote a safe engagement in gym activities (Henning and Andreasson, 2022). The potential negative health impact of PES use and its increased prevalence in gym-goers (Lazuras et al., 2017; Tavares et al., 2020b), focusing on individuals’ capacity to develop health assets that empower them to engage in health-protective behaviors (Morgan and Ziglio, 2007) requires an understanding of the profile of those who do not consider or refuse PES use.

Therefore, understanding the motivations of those gym-goers who reject PES, despite social pressure to consume (Copeland and Potwarka, 2016), may involve identifying a set of beliefs, attitudes, norms, and intentions, concerning substance use (Barkoukis et al., 2013). Following recent research that explained these cognitive aspects associated with PES use in the fitness context (Tavares et al., 2020a), the present study adopts the main concepts of the Theory of Planned Behavior (TPB; Ajzen and Fishbein, 1980; Ajzen, 1991) to explain the determinants of non-use of PES.

Over the past years, researchers have found that athletes’ substance use is determined by their intentions to engage in behaviors aimed at improving performance (e.g., Barkoukis et al., 2013; Ntoumanis et al., 2014). According to researchers who have conducted studies based on TPB (e.g., Chan et al., 2015a; Kirby et al., 2016), these intentions for PES use, in turn, are determined by three main social cognitive factors. First, they are influenced by athletes’ attitudes toward substance use. Attitudes toward PES use depends on the beliefs about the outcomes of the behavior and the judgments about its personal consequences, that is, the costs and benefits associated with substance use, as well as the emotional value athletes attach to these consequences. Second, intentions are determined by the subjective norms related to substance use. Subjective norms represent individuals’ perceptions of what their significant others believe they should do (normative beliefs) and whether they are motivated to act accordingly to those beliefs (motivation to comply) (Albarracín et al., 2001). Lastly, the perceived behavioral control (PBC) over PES consumption refers to one’s beliefs about the barriers and the perceived power one exerts over those barriers. In addition to its influence on intentions, PBC also directly influences behaviors when individuals have incomplete control over the behavior (Martinez and Lewis, 2016).

The TPB framework has also been utilized to explain PES use in gym-goers. Allahverdipour et al. (2012) were able to predict 63% of the intention to use PES based on PBC, subjective norm and attitudes. However, intention was the only variable that predicted self-reported PES use. Based on TPB, Tavares et al. (2019b) conducted a validation study on the Questionnaire of Attitudes toward Doping in Fitness (QAD-FIT). The emerging factor structure resulted in an instrument that assesses four dimensions related to the psychosocial aspects of PES use within the context of fitness. These dimensions consisted of attitudes, subjective norms, beliefs, and intentions regarding PES use. Subjective norms were the strongest predictor of intentions, followed by beliefs and attitudes. The three variables predicted 75% of intentions to use PES, which in turn predicted 44% of PES use. Subjective norms as the strongest predictor supports the important role of perceived social norms; indeed, first-hand accounts of peers have been identified as a major source of information for anabolic steroids users in the gym population (Kimergård, 2015).

Some research has explored the reasons behind not using PES. In a large study that encompassed five European countries, the most frequent reasons for young adults not to engage in this behavior were worry about the negative health impact, not feeling the need to use them, and a desire to find out how much individuals can achieve on their own. Not being able to afford these substances or not having access to them were not generally important reasons for non-use (Lazuras et al., 2017). These results reinforce the need for educational practices that emphasize the development of individuals’ empowerment.

In addition to these psychosocial determinants other demographic variables are likely to influence behavior. For example, being male, having lower educational qualifications, being unemployed, high training frequency and practicing bodybuilding were more likely to engage in PES compared to their counterparts (Tavares et al., 2022). A global profile of PES users further included “a desire to increase muscle mass, shape their body, and improve physical condition; being advised by friends, training colleagues and coaches or on the Internet” (p.10). Moreover, AAS male users demonstrated greater likelihood to meet criteria for substance dependence disorder, and reported having an anxiety disorder, frequent recent use of cocaine and a history of sexual abuse (Ip et al., 2011) when compared to their male non-user counterparts.

Considering the evidence that suggests the involvement of cognitive determinants in PES use (e.g., Wiefferink et al., 2008; Tavares et al., 2019a,2020a), it is important to understand how these determinants can constitute protective factors in individuals who do not report use of PES. Therefore, the present study’s main objective is to identify the profile of the non-use of PES of gym-goers. Accordingly, it is expected that unfavorable attitude toward substance consumption, the absence of a subjective norm that emphasizes consumption and, finally, unfavorable beliefs about the outcomes of PES consumption are associated with reports of non-use of PES. Additionally, it is also hypothesized that intentions toward PES use is negatively associated with self-reports of PES non-use. Finally, it is hypothesized that females and those who practice non-strength-based activities are more likely to report non-use of PES.

Research on doping and performance enhancement substances, both in competitive sport and in recreational fitness context have mostly focused on the population that consumes this type of products (Wiefferink et al., 2008; Tavares et al., 2020b; García-Grimau et al., 2021). Among these studies several of them have used the TPB to predict this kind of behaviors (Chan et al., 2015a; Kirby et al., 2016; Tavares et al., 2020a). However, as far as we know, no studies have been developed to investigate the protective factors of PES use in fitness context related to non-user population, considering the components of TPB, although a considerable number of studies try to understand why athletes refrain from engaging in PES, on the broad sport context (Leone and Fetro, 2007; Bloodworth and McNamee, 2010; Zenic et al., 2013; Erickson et al., 2015). Therefore, the main purpose of this study was to identify the profile characteristics of the non-use of PES of gym- goers, following the same approach of Tavares et al. (2020a) used to study the determinants to consume PES in the same population. Moreover, the association of gender and type of sport activity with the self-reported behavior of PES was also studied.

More specifically, hypotheses state that the unfavorable evaluation of attitude toward substance consumption, the absence of a subjective norm that emphasizes consumption, and the unfavorable beliefs about the outcomes of PES consumption are associated with the intentions of PES non-use. In line with previous studies (e.g., Lucidi et al., 2004, 2008; Allahverdipour et al., 2012; Chan et al., 2015a), results of the multiple linear regression confirm these hypotheses suggesting that the variation of scores on these variables have a direct and positive relationship with the intention scores. It was also expected that favorable intentions toward PES use were negatively associated with self-reports of PES non-use behavior. In fact, in the current study, when beliefs, subjective norms, intention, and attitudes were considered, only intention was significantly associated to the PES non-use which is supported by the fact that among the non-consuming subjects 97% have a negative intention to use PES. Moreover, when all the components were included in the decision tree model, only intention proved to be significant. This is consistent with the TPB model and results from previous studies investigating PES use (e.g., Lucidi et al., 2004, 2008; Wiefferink et al., 2008) suggesting the need to promote behavior free of PES through educational interventions emphasizing the determinants of intentions of healthy behaviors. For example, taking into consideration the relationship between attitudes and subjective norms with intentions, a main target of educational programs should be the social context of individuals namely the instructors of clubs and exercise centers. Additionally, educational programs aiming at preventing gym-goers’s use of PES should also convey information on the potentially dangerous impact of these substances on health so that negative intentions toward PES develop.

The final hypothesis is also confirmed. It stated that the female practitioners and those who practice non-strength-based activities are more likely to report non-use of PES. Results show the importance of gender as 94.5% of women do not consume PES versus 80% of men, which is in line with other studies (Serpa et al., 2003; Ntoumanis et al., 2014; Sagoe et al., 2015; Backhouse et al., 2016; Nicholls et al., 2017; Tavares et al., 2020a; Collomp et al., 2022). As to the type of activity, 98.1% of the non-consuming subjects do not practice bodybuilding. Additionally, results show that 95.5% of those who have a lower training frequency, and 88% of those who practice functional training, are not PES consumers. These results may be explained by the fact that activities such as cardio fitness, stretching or localized gymnastics are not so connected with results influenced by those substances versus strength-based activities (Wichstrøm, 2006; Tavares et al., 2020b; Mantri et al., 2023). On the other hand, female subjects in the current study are mostly involved in those types of exercising and they may have motivations related to general physical wellbeing instead of over-shaping their muscles with the help of PES. In what concerns the frequency of training per week, it may suggest that physical wellbeing and health goals may be the main purposes to be reached by the lower frequent practitioners. Moreover, in this group there is a significant association with not practicing bodybuilding activities that are very much connected to a certain type of extrinsic social motives facilitating the use of external enhancers (Macho et al., 2021). On the other hand, among the subjects that have a higher frequency per week, most of those who are involved in functional training are PES non-consumers, which suggests that their aim may be being in good physical shape by means of a natural physiological process.

It was also found that the male group under 25 years old emerges significantly as PES non-consumers when compared to older male subjects perhaps because in this period of life subjects feel comfortable with their physical capacities and do not feel the need to enhance them with the help of specific substances. Moreover, intrinsic motives may be stronger than extrinsic ones, which are more strongly related to the use of PES (Ip et al., 2015).

Several aspects were found that are associated to the behaviors of not using PES in the gym-goers population, which are related (i) to cognitive factors analyzed through the TPB framework, (ii) to the subjects’ characteristics and their behavioral approach to the activities, and (iii) to the chosen type of activities. Regarding the cognitive factors, results suggest that intentions related to the PES non-use are strongly associated to this actual behavior. Moreover, individuals who have a negative intention to consume PES do not consume it. As to gender, age and time commitment, female, and younger male gym-users and those with lower frequency of gym activities show the higher percentage of non-use of PES. Regarding the activities, results suggest that functional training and not being involved in bodybuilding are associated to PES non-use.

In conclusion, this study shed light on fundamental aspects related to the decision not to use performance-enhancing substances among gym-goers. Findings showed that cognitive factors, particularly negative intentions, play a crucial role in the conscious choice not to use these substances. Furthermore, distinct demographic differences emerged, highlighting a gender disparity, with 94.5% of women and 80% of men opting not to use these substances. Age was also an important characteristic with younger men, especially those under 25, demonstrating significant resistance to PES use, possibly driven by intrinsic motivations and satisfaction with their physical abilities. Regarding activities, those engaged in functional training and not practicing bodybuilding showed a clear preference for not resorting to these substances. Indeed, these younger men may search mostly for the pleasure of the chosen physical practice and not just for its outcome. Moreover, in the younger ages physiological and morphological results are faster and more evident which may reduce the wish to enhance them with PES. Thus, this work provides valuable insights, showing the way for more refined interventions aimed at promoting a culture of health and substance-free fitness practices.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving humans were approved by the Ethical Committee of the University of Lisbon, Faculty of Human Kinetics. The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study.

AT: Conceptualization, Data curation, Funding acquisition, Investigation, Methodology, Project administration, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing. EC: Data curation, Formal analysis, Methodology, Writing – review & editing. PT: Supervision, Writing – original draft, Writing – review & editing. LC: Supervision, Writing – original draft, Writing – review & editing. SS: Conceptualization, Data curation, Methodology, Supervision, Writing – original draft, Writing – review & editing.