“No pain, no gain” is an adage that most athletes would agree with. Elite athletes in particular commonly exceed their physical and psychological limits during training and competition, despite experiencing pain (1, 2). Nixon (3) reported that about 94% of college athletes participated in sports competitions despite being injured. Thus, it appears likely that injured athletes' participation is facilitated by the use of non-steroidal anti-inflammatory drugs (NSAIDs), which are widely used among athletes. Thus, it seems to be obvious that athletes are familiar with the use of painkillers. Studies show that the prevalence of NSAID use in competitive sports ranges from 40 (4) to 86% (5). High rates of NSAID use were identified among Olympic athletes at the Sydney Games (1), in FIFA tournaments (2, 6), as well as in Finnish (7) and Belgian (8) elite athletes. However, the use of NSAIDs is not only a phenomenon related to elite sports. High consumption of NSAIDs has also been identified in non-elite participants of the Bonn (9) and Boston (10) marathons. Athletes consume NSAIDs for the treatment of injury-related pain, pain prevention (prophylactic use), reduction in recovery time and for performance improvement (11–15).

NSAID use is not a violation of Anti-Doping Rules per se. Consequently, numerous drugs used to treat pain do not appear on WADA's (16) list of prohibited substances. While NSAID use does not represent an Anti-Doping Rule violation, athletes do mention using them for performance enhancement (13). As a corollary, NSAID use can be seen as a risk factor for the misuse of other substances [see (17, 18)]. In addition, several studies have shown similarities between NSAID use and doping behavior. Research has confirmed that athletes with a strong intention for doping or a history of doping abuse are more likely to misuse other illicit substances [e.g., (19, 20)]. Lippi et al. (21) highlight that there is a “strict parallelism” (p. 105) between doping and medication, nutritional supplements, alcohol or social drug use. The use of NSAIDs has also been related to increased use of doping substances (22). Research shows that medication use is correlated with doping [e.g., (18, 20, 22)]. A question that arises from the many parallels between NSAID use and doping is whether NSAID use, like doping, is also related to positive attitudes toward doping.

Doping behavior is explained as a dynamic interplay between personal attributes (e.g., doping attitudes and/or personality factors) and situational factors (23). Most of the relevant integrative models on doping behavior [e.g., extended Theory of Planned Behavior (TPB), (24), Trans-contextual Model, (25), Life Cycle Model, (26), Sports Drug Control Model (SDCM), (27) describe doping as a goal-directed, intentional and self-regulated behavior that is based on individual decision-making processes both in a broader context and in specific situations. It is, however, unclear whether the use of NSAIDs is determined by a similar interplay between personal and situational factors, and if so, whether certain factors explain NSAID use.

The personality factor competitive anxiety, which has not been widely investigated in relation to NSAID use, deserves special consideration. In fact, few studies focus on the role of anxiety in the use of legal and illegal substances in sports. Studies that have investigated the relationship between anxiety and doping or substance abuse in sport have found a positive correlation [e.g., (28–32)]. Results of these sport-specific studies confirm that one important reason for substance abuse is anxiety reduction (33).

Another aspect relevant to NSAID use is the situation itself. In their doping model, Lazuras et al. (24) include the variable situational temptation, which is the perceived temptation to engage in doping under certain conditions. The SDCM (27) also includes situational variables to explain doping, such as drug affordability and availability. Moreover, the SDCM's appraisal of threat and benefit are perceived evaluations of the situational conditions (e.g., perceived likelihood of being tested or sanctioned). According to the SDCM, consumption of doping substances will be high if threat appraisal is low and benefit appraisal is high [see (27)].

Although situation is clearly an explanatory factor in doping behavior models, few studies have investigated effects of the immediate situation on doping use [e.g., (26, 34, 35)]. The Rational Choice Theory [RCT, (36)] postulates that a person is likely to engage in deviant behavior if their assessment of the circumstances leads them to believe they could obtain a desired outcome in which expected gains would outweigh potential costs. According to RCT, a person's chosen methods are then guided and constrained by rational considerations. Following this theoretical viewpoint, individuals seek to maximize personal benefit and minimize costs or risks. Rational decision-making in situations which involve deviant behavior is characterized by a brief cost-and-benefit appraisal. Decisions are predominantly motivated by reward, perceived as temptation, and less by fear of being convicted (37).

Our assumption is that NSAID consumption will be more frequent in low-cost situations in which the benefit is high and risk is low, as opposed to high-cost situations in which the risk of being caught is high and chances for personal benefit are low. Furthermore, we assume that the personality factor anxiety will play a different role in favorable (low-cost) as opposed to unfavorable (high-cost) situations. That is, we assume that anxiety will show a stronger influence on NSAID use in favorable situations characterized by low costs (38).

On the other hand, a positive attitude toward doping is assumed to have a strong impact on doping behavior in both favorable and unfavorable situations. This is based on results showing that perceived opportunity does not substantially influence behavior when strong attitudes prevail [see (39)]. In a way similar to a distorting lens, strong attitudes affect perception of a situation and lead to less deliberation and an automatic behavior pattern regardless of situational context factors. Once in a situation, perceptive biases lead to a strong and easily assessable doping attitude, which may in result in positive doping behavior, and/or the decision to use NSAIDs.

This study investigates three research questions. The first question interrogates whether the use of NSAIDs, a behavior presumably analogous to doping, is related to doping attitudes. We assume positive correlations between the hypothetical consumption of NSAIDs and doping attitudes.

The second research question investigates if competitive anxiety is related to situations characterizing NSAID use. We assume that competitive anxiety is related to the hypothetical use of NSAIDs.

The third question investigates if the likelihood of NSAID use is dependent on situational condition. We assume that NSAID use is indicated if the situation is favorable rather than unfavorable. A favorable situation is characterized by the absence of potential witnesses and the presence of an attractive good (40). We also assume that anxiety is more strongly related to NSAID consumption if the situation is favorable rather than unfavorable.

Descriptive analysis results are presented in Table 1. Correlations between the measured dependent and independent variables are presented in Table 2.

First, we analyzed if doping attitudes were related to NSAID use. Bivariate correlation analyses showed positive significant correlations for both unfavorable and favorable NSAID use conditions.

In a second step, we investigated correlations between the two situations and anxiety. We found positive correlations between the favorable condition and worry and somatic anxiety, and between the unfavorable situation and the worry component of competitive anxiety.

In a third step, we investigated the difference between NSAID use in favorable and unfavorable situations with a univariate repeated measures ANOVA. The mean difference was significant and the effect size was substantial F _{(1, 121)} = 38.90, p < 0.01, η²= 0.24. Athletes were more likely to use NSAIDs in the favorable than in the unfavorable situation.

Lastly, we investigated the influence of doping attitudes and competitive anxiety on NSAID use in both situations. Prior to conducting the two hierarchical regression analyses, we verified assumptions for regression analysis and considered biasing influences (46). These tests confirmed satisfactory quality of the data set for conducting a hierarchical regression analysis.

With regard to the first set of research questions, results indicate that the decision to use NSAIDs is moderately correlated with doping attitude. This supports the assumption that the use of NSAIDs is a behavior parallel to doping. This result confirms previous research indicating that doping behavior and NSAID consumption are correlated (22).

With regard to the second research question investigating competitive anxiety, results show that the worry component in particular is associated with NSAID use in both situational conditions. Athletes with a tendency to experience high worry and high somatic anxiety in competitions are more likely to use analgesic substances in favorable situations. Athletes with a tendency to experience only high worry in competitive situations are even more likely to use analgesic substances regardless of the situation. So far, the relationship between anxiety and NSAID use has not been widely investigated. The results of this study contribute to furthering our understanding of the relationship between the two and suggest that NSAID consumption could be related to anxiety reduction (33).

With regard to the third research question, our study results indicate that the immediate situation is relevant for NSAID use. The likelihood of using NSAIDs depends on situational conditions. Our study confirms that athletes were more likely to consume NSAIDs in a favorable situation with a lower risk of detection and expected higher benefits. These results are in line with the Low-Cost Hypothesis [for an overview: (38)] and Rational Choice Theory (36). Previous studies of deviant and criminal behavior have shown that if the perceived benefit exceeds the expected risk, the likelihood of different deviant behaviors such as shoplifting, drunk driving, stealing or buying illegal drugs increases, as well [e.g., (40, 50–52)]. Our results are also in line with the expected outcome of the SDCM (27) and the Drugs in Sport Deterrence Model [DSMD, (53)].

We also assumed that anxiety is more strongly related to NSAID consumption if the situation is favorable rather than unfavorable. Looking at the correlations we can see that worry and somatic anxiety were positively related in the favorable situation, whereas only worry was correlated in the unfavorable situation. Results of the regression analysis highlight that in the favorable situation, worry had a significant impact on NSAID use, which explained even more variance than doping attitudes. In the unfavorable situation, worry was also a significant predictor; however, doping attitudes explained significantly more variance regarding impacts on NSAID use. This means that in a situation with little risk of being caught and some incentive, athletes with high somatic anxiety and high worry might cope with the stressful situation by resorting to substance use. In the unfavorable situation, however, substance use among athletes experiencing higher levels of worry is more dependent on whether they also have positive attitudes toward doping and not solely explained by their high worry. These results confirm our hypothesis that the relationship between anxiety and NSAID consumption depends on perceived cost of the situation, whereby anxiety seems to play a larger role if situational costs are low.

Our results suggest that factors contributing to NSAID consumption are associated to those of doping, as is the case with analogous behaviors such as nutritional supplement intake or recreational and illicit drug use (18, 19, 54, 55). Therefore, NSAID use should be considered a gateway for doping, as both share similar underlying mechanisms (18, 55). Furthermore, our results indicate that not only athletes with positive doping attitudes but also athletes with high anxiety are at risk, especially in the favorable situation.

This study identified that NSAID use can be described as a behavior analogous to doping. Furthermore, the personality factor competitive anxiety, in addition to doping attitudes, was found to be related to NSAID consumption. Therefore, further research should examine whether competitive anxiety is a potential risk factor for doping. The study further highlights that conducting research on doping should consider the situation. That is, different factors influence the decision for NSAID use in unfavorable vs. favorable situations.

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

Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. The patients/participants provided their written informed consent to participate in this study.

MM designed the study and collected and analyzed the data. KS and MM drafted the manuscript. KS and A-ME conducted additional data analyses. A-ME critically reviewed the manuscript. All authors contributed to the article and approved the final version.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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