In this study it, can be observed that most of the participants did not use AS, whereas 9.1% formerly used, 3.4% currently used, and 4.3% thought intended to use AS. Previous studies [19, 20] evaluating AS use among resistance training practitioners grouped individuals who had used AS together with those who were using AS, thus resulting in lower prevalence than that found in our study; if the prevalence in the Gex and Gus groups were grouped, the prevalence would be higher (12.5%) than that in the previous study.
The sample size of gyms and participants in the literature also varied. A study in Germany carried out roughly 15 year ago evaluated 113 gyms and 621 individuals, and showed a prevalence of AS use of 13.5% . In Stockholm, Sweden, the prevalence was 3.8% with 64 gyms and 1746 individuals . In Al-Ain, United Arab Emirates, the prevalence was 22.1% with 18 gyms and 154 individuals . However, other studies were restricted to smaller samples; for example, a study in El Paso, United States, evaluated three gyms and 516 individuals, showing a prevalence of 11.0% . Moreover, a study in Boston, United States, examined five gyms and 511 individuals, showing a prevalence of 5, 1% . The variability of the prevalence among these studies can be attributed to not only the sample distribution, namely the numbers of gyms and individuals, but also the regional and own characteristics of the samples. For example, in the Netherlands, a study involving 92 gyms and 718 individuals obtained a prevalence of AS use of 1% . However, compared with the other studies, this study had a higher percentage of women (64%) and higher mean age (43.4 ± 13.6 years), which may explain why the number of women using AS was shown lower than that of men using AS.
The percentage of individuals who formerly used AS in the present study (9.1%) was higher than that in a meta-analysis involving 271 articles (3.3%) . However, in this meta-analysis, the sample was heterogeneous because it included adolescents, university students, prisoners, military, bodybuilders, athletes, and sedentary people, among others. On the contrary, the present study examined only resistance training practitioners.
In Brazil, a systematic review presented a prevalence range of AS use of 2.1 to 31.6%, with a heterogeneous sample . Specifically, in resistance training practitioners, the prevalence ranged from 4.5 to 24.9%. These studies showed the profile of various regions in terms of AS use, but some had relatively small sample sizes of both gyms and individuals.
The distinction between former (Gex) and current (Gus) users helped us understand the profile of AS users. Some individuals may have used AS to experiment at some point in their life and had not used it any more, whereas others may use AS recurrently. In a study conducted in Sweden, was assessed individuals who used AS at some point in their life (2.6%), within less than 12 months (0.9%), and within less than 30 days (0.3%) . The results showed that, as in the present study, the number of individuals who had used AS is higher than that of individuals currently using AS.
In the present study, it was possible to calculate prevalence ratio owing to the large sample size. There was a higher prevalence of AS users among men than among women, which corroborated with literature [7, 27]. Furthermore, other studies presented a prevalence close to 5.7%  and 7% . However, some studies did not report the use of AS by women [15, 23, 29]. AS consumption is lower among women because they do not wish to become extremely muscular or develop male characteristics . In comparison, among men, the motivation of using AS goes beyond developing the ideal body; they use AS to gain status, admiration, and popularity in their social environment . In addition, AS usage allows acceptance from and identification with their peers .
The current study, questionnaires were distributed proportionally to the number of individuals per period. The afternoon period presented a greater percentage of former, current, and future users of AS; thus, it was concluded that the highest prevalence of AS use occurred in the afternoon. This finding was not observed in any other study. We hypothesized that the afternoon showed greater number of AS users because the gyms were emptier during this period than during other periods in the day, which minimized interference during the course of training because the devices were shared with other practitioners.
In the present study, participants aged between 18 and 29 years presented the highest percentage of future AS users. Therefore, this age group should be the target of future education and preventive actions regarding abusive AS use. Participants aged between 30 and 44 years old showed high prevalence of former AS users (11.6%), whereas in other studies, high prevalence was shown by those aged between 18 and 29 years [14,15,16].
The search for improvements in quality of life, along with increasing advancement of antiaging therapies, may have prompted the increase in the use of AS. Older people have shown interests in hormone replacement; however, this treatment may cause a number of undesirable effects in young people . Age-related physiological decline and societal pressure on body image are factors contributing to the increased use of AS in older men .
In the age group of 45–59 years, the prevalence of non-users of AS was the highest. It was verified that the frequency of AS and the number of resistance training practitioners decrease with age, showing that this activity is probably not the most sought after by this age group. Among single participants, there were high percentages of former and future users of AS. Although this high prevalence of former users of AS is supported by the literature [16, 22, 34], no previous study evaluated individuals who intended to use AS.
Most of the participants had complete upper secondary education, as observed in other studies [13, 15]; thus, it was suggested that people with lower level of education showed lower adherence to resistance training. There was a higher percentage of individuals with incomplete upper and lower secondary education among future users of AS, corresponding to individuals aged between 18 and 29 years, which showed the highest frequency of future users of AS. This finding emphasized the need for orientation regarding the use of AS in schools and universities, considering that AS use was also high in individuals with incomplete upper secondary education .
The prevalence of AS use was higher in individuals who had been practicing resistance training for a longer time. Previous studies have shown that AS use is higher in those who have been training for more than 2 years [14, 19, 23]. The frequency of sessions per week also showed similar, in accordance with the literature, which showed higher prevalence for train five times or more per week [14, 16, 19]. This higher frequency may be related to the awareness of the need for concomitant use of AS with training to obtain the desired result. Moreover, considering that these individuals train regularly, another possible motivation may be that they have not achieved the desired result solely through training.
This study found that the main objective of resistance training was muscle hypertrophy, which is consistent with the literature [13, 33]. The percentage of individuals who formerly used, currently using, or intended to use AS was high among these practitioners because they sought higher increase in muscle mass .
The number of individuals who had nutritional monitoring (28.7%) in this study was higher than that found by Silva et al., 2007  (13.9%). In our study, among these individuals, 42.3% used supplements, and this number is higher than the 26% observed by Pellegrini et al., 2017 . The prescription of supplements is the responsibility of a nutritionist, but instead, the resistance training coaches gave the prescription .
The use of food supplements in Brazil has varied from 20.5 to 94.0% among practitioners of physical activities [13, 36, 37], and our current result was within this range (40.4%). Among AS users, these values increased to 80% , which is close to our current results, namely 73.1 and 89.7% in former and current users of AS, respectively. Thus, it was indicated that individuals who use AS are more likely to use supplements [13, 22]. In our results, protein was the most common supplement used, in accordance with previous studies [13, 14, 16], because protein supplements help to achieve muscle hypertrophy, which is one of the objectives of these practitioners . Also, the addiction must be considered as a potential complication of innapropriate use of AS .
The limitations of the present study included possible response bias. The participants may have not provided a response representing reality because they were using AS for non-therapeutic reasons.