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 Table of Contents  
ORIGINAL ARTICLE
Year : 2019  |  Volume : 2  |  Issue : 3  |  Page : 126-137

Use of ergogenic supplements by young athletes in a sports specialized school


1 Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston, TIRR Memorial Hermann, Houston, Texas, USA
2 Department of Physical Medicine and Rehabilitation, University of Puerto Rico, School of Medicine, San Juan, Puerto Rico, USA
3 Department of Physical Medicine and Rehabilitation, Mayo Clinic, Jacksonville, Florida, USA
4 Puerto Rico Clinical and Translational Research Center, Medical Sciences Campus University of Puerto Rico, San Juan, Puerto Rico, USA
5 Department of Physical Medicine and Rehabilitation; Department of Physiology and Biophysics, University of Puerto Rico School of Medicine, San Juan, Puerto Rico, USA

Date of Submission20-Jun-2019
Date of Decision10-Jul-2019
Date of Acceptance15-Jul-2019
Date of Web Publication25-Oct-2019

Correspondence Address:
Dr. Manuel F Mas
Carr 844 Km 0.5 Cupey Bajo, San Juan, Puerto Rico, 00928
USA
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jisprm.jisprm_55_19

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  Abstract 


Background: Few studies have examined the use of ergogenic supplements (ESs) by young athletes residing in a sports specialized school. Methods: In this cross-sectional study, 120 students from a sports specialized school (ages 12–19) completed a questionnaire to assess the prevalence of use of ES according to sex, sport, type of supplement, reasons for use, knowledge of supplements, and sources of information. Results: Most athletes were males (55%) and participated in track and field (32%). Mean age was 14.7 ± 1.6 years. Approximately 98% of athletes indicated using one or more supplements. Sport beverages (95.0%), proteins/amino acids (57%), and vitamins (54%) were the most commonly used. Athletes practicing racquet sports were more likely to consume proteins/amino acids every day than those in any other type of sport (P < 0.05). The adjusted odds of using vitamins were 14% (95% confidence interval [CI]: 0.22–3.30) and 71% (95% CI: 0.09–0.96) lower among athletes practicing explosive sports and high intensity, respectively, as compared to those practicing endurance-intensive sports. On the other hand, the odds of using proteins/amino acids was higher for those practicing explosive (adjusted odds ratio [AOR]: 3.48, 95% CI: 1.02–11.86) and high-intensity (AOR: 2.88, 95% CI: 1.00–8.26) sports. Approximately 62% of athletes used supplements to improve performance. Only 8% of athletes were willing to use a prohibited substance to achieve participation in the Olympics. Conclusion: There was a very high prevalence of use of ES in a sports specialized school. Education regarding supplement use is warranted for athletes, coaches, and family.

Keywords: Adolescents, ergogenic aids, nutritional, nutritional supplements, pediatric, sports nutrition, sports supplements


How to cite this article:
Mas MF, Ranal JL, Rosario Concepcion RA, Gonzalez-Sepulveda L, Rivas-Tumanyan S, Frontera WR, Ramos E. Use of ergogenic supplements by young athletes in a sports specialized school. J Int Soc Phys Rehabil Med 2019;2:126-37

How to cite this URL:
Mas MF, Ranal JL, Rosario Concepcion RA, Gonzalez-Sepulveda L, Rivas-Tumanyan S, Frontera WR, Ramos E. Use of ergogenic supplements by young athletes in a sports specialized school. J Int Soc Phys Rehabil Med [serial online] 2019 [cited 2019 Dec 16];2:126-37. Available from: http://www.jisprm.org/text.asp?2019/2/3/126/269960




  Introduction Top


The use of ergogenic supplements (ESs) in the general population has increased in the past decades.[1] This is more evident among athletes, where the prevalence of use is reported to range between 65% and 88%[2] despite the lack of evidence supporting their alleged benefits.[3],[4] In fact, some studies have reported detrimental effects when high quantities are used for prolonged periods.[5] In the present study, we define ES as any external influence that may enhance athletic performance or facilitate physical exercise.[6],[7] Most athletes who use ES do not have sufficient knowledge regarding their safety or efficacy.[2]

The general adolescent population is not exempt from this surge in ES use with a reported prevalence of use of 71%[8] and 80%–100% in young athletes.[9],[10] This is worrisome considering that children and adolescents have special nutritional needs and that some of these substances may be associated with health risks.[11] ES does not require testing by the Food and Drug Administration and claims of safety and product quality cannot be verified.[12] The reasons behind the use of these substances range from health benefits to performance improvement,[13] but there is evidence of widespread misinformation and incongruence in their use.[14]

There is currently a lack of information regarding the prevalence and reasons for the use of ES in the young athlete population. Only a handful of studies detail their use in this subgroup.[2],[9],[10],[13],[14] To the best of our knowledge, there are no studies focusing on young athletes residing in a sports specialized school. Therefore, the objectives of this study were to: (1) Estimate the prevalence of use of ES among young athletes in a sports specialized school (2), identify the reasons for using ES, and (3) study the association between the use of ES and the type of sport, sex, and age of the participants.


  Methods Top


Study population

The study population consisted of students from a residential sports specialized school located in Salinas, Puerto Rico at the Olympic Training Center. The school is government-funded and houses a total of 300 students ages 12–19 in Grades 7–12. The students live in the school from Sunday to Friday, take regular academic courses during the day, and train twice a day Monday to Thursday. They also compete on some weekends. Because of their level of training and competition, they were classified as highly trained athletes.[10]

The study was approved by the Institutional Review Board of the University of Puerto Rico, Medical Sciences Campus. Athletes and their guardians received information about the purpose of the study. A consent form was given to their parents for authorization as well as an assent form for the athletes themselves. One week later, surveys (see below) were completed by the students in their classrooms.

Survey

The survey was designed by the authors based on published instruments.[2],[8],[9],[14] The anonymous survey included demographic information, patterns of use of ES, reasons for use, knowledge about ES, and attitudes toward ES (including the willingness to use the prohibited substance to participate in Olympic events) in the past 12 months (see details below). The term “ES” was not defined for the athletes. Before the administration of the survey, a draft was provided to a sample of young athletes attending the sports specialized school. Feedback was specifically sought on language and content. Then, the survey was presented to a research committee (including sports medicine physicians), an epidemiologist, and departmental faculty for further reactions. The survey is included in both its original language, Spanish, and an English translation in Appendices 1 and 2, respectively.

Study variables

The main outcome was the frequency of use (yes/no) of the following supplements: vitamins, proteins/amino acids, sport beverages, and ergogenic aids (i.e., caffeine and creatinine). The frequency of use of these supplements was evaluated using the following categories: never, several times a month, several times a week, and every day. The reasons for using supplements (i.e., performance, avoid lesions, prevent diseases, improve physical appearance, and recommendation) were used as secondary outcome. Sports were classified into five groups as described in previous studies,[9] including track and field (i.e., sprints, race walking, middle distance, throwing, jumping, and multiple events), racquet sport (i.e., tennis and table tennis), ball sports (i.e., volleyball, handball, and basketball), combat sports (i.e., boxing, judo taekwondo, Olympic wrestling, and combat), and others (e.g., swimming, triathlon, shooting sports, Olympic weightlifting, and fencing). Further, sports were categorized based on the duration of all-out effort, in three categories [15] including: explosive (i.e., jumping, throwing, sprints, and Olympic weightlifting), high intensity (i.e., volleyball, handball, basketball, table tennis, tennis, boxing, judo, taekwondo, Olympic wrestling, combat, and multiple events), and endurance-intensive sports (i.e., swimming, triathlon, race-walking, and middle distance).

Statistical analysis

Descriptive statistics were used to characterize the study population. The association between the type of sports and use of any type of ES and ES use frequency was assessed using Fisher's exact or Chi-square tests, as appropriate. To further evaluate the associations between sports and use of ES, logistic regression models were performed using bootstrapping with a total of 500 replications, to estimate the age and sex adjusted odds ratios (AORs) and 95% bias-corrected confidence intervals (CI). This analysis was also performed to estimate the magnitude of the association between reasons to use supplements (as outcomes) and types of supplement and sports. All the statistical analyses were performed using Stata v. 14 (College Station, Texas 77845 USA). A value of P < 0.05 was considered statistically significant.


  Results Top


The characteristics of the 120 participants are included in [Table 1]. The mean age was 14.7 ± 1.6 years and most of the athletes were males (55.0%). High school students represented 54% of the total number of students. Most students participated in track and field events, high-intensity sports, and reported using sports beverages. No association was found between sex or age group and the use of ES.
Table 1: Participants' characteristics (n= 120)

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[Table 2] presents the use of various ES by type of sport as well as sport based on the duration of all-out effort. In general, 98% of the athletes indicated using one or more supplements and 18% reported using more than three supplements. The most commonly used supplements were sports beverages (95%), proteins/amino acids (56%), and vitamins (54%). Athletes reported that their main source of information regarding these supplements were coaches (52%) and family members (34%).
Table 2: Association between the type of sports and the use of supplements (vitamins, proteins/amino acids, sport beverages, and ergogenic aids) among all participants (n= 120)

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When analyzing frequency of use by type of sport, athletes practicing racquet sports (46%) were more likely to consume proteins/amino acids supplements every day, compared to those practicing track and field (18%), ball sports (8%), combat sports (32%), and other sports (32%) [Overall Fisher's exact test P = 0.03; [Figure 1]. The frequency of consumption of other supplements such as vitamins, ergogenic aids (caffeine and creatinine), and sport beverages was not different among sport groups [P > 0.05; [Figure 1]. The frequency of consumption of all supplement categories was not statistically significantly different between sports classified based on the duration of all-out effort [P > 0.05; [Figure 2].
Figure 1: Association between frequency of supplement use and types of sport (n = 120). Note: Ergogenic aids included caffeine and creatinine. P values were calculated using Fisher's exact test

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Figure 2: Association between frequency of supplement use and sports based on exercise duration of all-out effort (n = 114). Note: Participants practicing shooting sports and fencing were not included (n = 6). Ergogenic aids included caffeine and creatinine. P values were calculated using Fisher's exact test

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Associations between supplements and sports categories are also shown in [Table 2]. Use of vitamins and proteins/amino acids (use vs. nonuse) was different across the type of sport and sports based on the duration of all-out effort (P< 0.05), while no association was found with ergogenic aids or sport beverages (P > 0.05). After adjusting for age and sex, athletes practicing ball sports showed 86% lower odds (95% CI: 0.03–0.68) of using vitamins compared to athletes practicing other sports. Meanwhile, athletes in “other sports” category had about 90% lower odds (95% CI: 0.03–0.42) of using proteins/amino acids supplements compared to athletes practicing racquet sports.

When we categorized sports based on the duration of all-out effort, the odds (adjusted) of using vitamins were 14% (95% CI: 0.22–3.30) and 71% (95% CI: 0.09–0.96) lower among athletes practicing explosive sports and high intensity, respectively, as compared to those practicing endurance-intensive sports. On the other hand, 3.48 (95% CI: 1.02–11.86) and 2.88 (95% CI: 1.00–8.26) times higher adjusted odds of using proteins/amino acids were found among athletes performing explosive and high-intensity sports, respectively, as compared to athletes executing endurance-intensive sports.

The main reported reason to use supplements was to improve performance (62%). Some athletes indicated they have used supplements to avoid injuries (20%), prevent diseases (23%), or because it was recommended by physicians and/or family members (24%). A minority of athletes (8%) were willing to use a prohibited substance to achieve participation in the Olympics. [Table 3] shows the association between the main reasons for using supplements and the use of each supplement and sport categories. No association was found between the use of ES and any of the reasons to use supplements in the entire population [P > 0.05; [Table 3]. Athletes using vitamins and proteins/amino acids had about 3.41 (95% CI: 1.15–10.12) and 7.34 (95% CI: 2.01–24.43) times higher adjusted odds, respectively, of considering injury avoidance as their main reason to use supplements, than those not using these supplements. Vitamin use was associated with higher odds of athletes indicating that they use supplements to prevent diseases (AOR: 6.35, 95% CI: 2.04–19.79). A reverse association, however, was found between disease prevention and the use of sport beverages (AOR: 0.10, 95% CI: 0.02–0.53). Furthermore, athletes consuming proteins/amino acid supplements were more likely to indicate that they use supplements to improve performance (AOR: 2.43, 95% CI: 1.05–5.62).
Table 3: Odds ratios (95% confidence intervals) for reasons for supplement use among athletes using at least one type of supplement according to the use of specific supplements and type of sports (n= 118)

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In addition, athletes from both combat sports and “other sports” categories had lower adjusted odds for considering improvement of their physique (OR: 0.18, 95% CI: 0.04–0.78) and performance (OR: 0.25, 95% CI: 0.08–0.84), respectively, as their main reason to use supplements when compared to those practicing track and field sports. When classifying sports based on all-out effort, athletes in explosive and high-intensity sports were 5.92 (95% CI: 1.39–25.26) and 4.64 (95% CI: 1.18–18.26) times, respectively, more likely to report taking supplements to improve their physique, compared to those practicing endurance sports.


  Discussion Top


To our knowledge, this is the first study detailing the use of ES by a young athlete population residing in a sports specialized school. Our data show widespread use of ES by this population, with 98% using one or more during 12 months. The high prevalence of use in young athletes has been noted before [2],[9],[10],[13],[14],[16] with the level of competition cited as a major determining factor of use.[9],[17] We found a significantly elevated prevalence of use of ES in young athletes at a sports specialized school. Although the use of a loose term such as “ergogenic aid or substance” may partially explain the high prevalence of use,[9] ES use in this sample of Puerto Rican, is notably elevated.

There is variability in the commonly used ES by young athlete populations. Sports drinks, proteins, and vitamins were most frequently used by the study population. However, others have cited minerals and vitamins [9],[10],[13],[18] and energy drinks [14] as the most frequently used supplements. This difference may be due to differences in the study design. For example, some of the previous studies not include sports drinks or beverages in their data collection instrument [13],[14] while others used the term “dietary supplement” without subdividing this into other categories.[16] Because the American College of Sports Medicine includes sports drinks in the category of ergogenic substances [19] and some studies have followed this definition [2],[9],[10] we believe it was appropriate to include it in the present study.

The weather in the site of the specialized school can be a contributing factor to the increased use of sports drinks and consequently, the elevated prevalence of supplement use. Temperatures and humidity in the area are high, with a reported average temperature of 35°C.[20] This makes hydration a key aspect to monitor during sport training and elevated temperature and humidity possible factors influencing the type of substance used.[19] These climatological factors could differentiate our population from others where sports drinks use were also reported.[2],[9],[10]

Young athletes who completed this survey resided in a sports specialized school, a scenario not previously evaluated in other studies. This environment could increase their likelihood of exposure to propaganda, information (or misinformation) from their peers and greater competitive pressure. It could also increase their motivation to perform better in their sport. This, in turn, can direct them to explore different alternatives that can provide a competitive edge. Cultural and ethnic factors can also play a role in supplement use by athletes. The study population was primarily Hispanic athletes, a group which tends to use more supplements than caucaseans.[21]

There was no statistically significant association between age or sex and frequency or reason to use of supplements. On the contrary, increased use of ES has been noted with older age [9] with some noting that older athletes could potentially be in a more competitive stage, willing to try different methods to succeed in their sport.[10] Sex has been reported to play a role in the use of ergogenic substances. Males generally utilize them to enhance performance, while females do so for recovery and health benefits.[2],[13],[16],[22],[23]

Every sport requires unique skills and different metabolic demands and therefore, ergogenic strategies may vary among different sports. When comparing sports based on all-out effort, athletes in our study population participating in explosive or high-intensity sports used more proteins when compared to endurance-intensive sports. A recent systematic review concluded that, when training is adequate, protein supplementation may enhance muscle mass and performance,[24] attributes that may benefit athletes in explosive sports. In contrast, endurance sports athletes used vitamins more than any other supplement. Adequate vitamin intake is important in an athlete's diet.[19] Endurance sports athletes' dietary energy intake is generally below their energy expenditure. Thus, endurance athletes in our population may be trying to compensate for this somehow with vitamin supplementation.

The only notable differences between supplement use when comparing the type of sport included: (1) increased the frequency of use of proteins and amino acids by athletes participating in racquet sports, and (2) decreased use of vitamins by athletes participating in ball sports. Regarding the decreased use of vitamins in ball sports, elite, junior basketball players have been found to use less Vitamin A, zinc, niacin, and calcium than the recommended nutritional guidelines.[25] Education targeting adequate intake of carbohydrates, proteins, vitamins, and minerals for this population has been recommended.[25]

In our population, those who used vitamins and minerals were more likely to use them to prevent illness although these types of ES are not recommended for this purpose.[9] Education regarding the proper use of ES could be beneficial not only for our population but also for their family and coaches, especially when the majority of athletes reported these as their main source of information.[16]

The safety of ES is not well-established in the pediatric population.[12],[26] Others have stated that these substances could be a gateway to the use of prohibited substances for the purpose of performance enhancement in the sport.[18],[27] Although in the minority, 8% of our athletes answered that they would be willing to use a prohibited substance if that meant being able to compete in an Olympic event. To our knowledge, this is the first time this question has been done in the young athlete population.

Yet, ES can be beneficial for athletes. In a recent position stand by the International Society of Sports Nutrition (ISSN), creatine supplementation has been recommended to enhance recovery from intensive training and injury, prevent injuries and enhance tolerance to exercise in the heat.[28] However, creatine use was under-reported in our population. Similarly, amino acids can improve performance when given to slower runners.[29] They can also decrease the sensation of fatigue and can help with mental performance when used during prolonged endurance events. The ISSN recommends using amino acids before, during, and following an exercise bout.[29] Thus, supplement use could be beneficial for athletes when used for appropriate and well-evidenced reasons.

Limitations of our study include are recall bias, which is inherent of any study with a similar design. Our sample was also small which could limit the power of statistical analysis.


  Conclusion Top


This is the first study describing the use of ESs in young athletes residing in a sport, specialized school. It is also the first to analyze ES use in sports categories based on the duration of all-out effort. High prevalence of use was evidenced, sports drinks being the most used substance among the population. Elevated temperature could be a factor influencing the high frequency and type of supplement used. Education regarding the proper use of these substances is warranted not only for athletes but also for their family and coaches. Future research with different study designs could assess the associations between ES use and other variables such as nutritional deficiencies. These proposed studies should also evaluate the level of knowledge of family members and coaches regarding the use of supplements. Finally, the association between increased performance and ES use must be studied in more details because this was the most cited reason for consumption in the population.

Acknowledgments

We would like to acknowledge the Puerto Rico Clinical and Translational Research Consortium for aiding in the design of the study, survey and data analysis. This publication was made possible in part to NIH Grants U54MD007587 and G12MD007583. All the authors were involved in study design, data collection, analysis, and the preparation of this written article.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.


  Appendices Top


Appendix 1

El cuestionario deberá ser contestado por el estudiante solamente.

Fecha _________________

Edad _______________ años

Género F ____ M ____

Grado _____

Tipo de deporte: __________________________



1. ¿Qué tipo de suplemento has utilizado en los pasados 12 meses? (Marque todas las que apliquen)

a. Creatina

b. Cafeína (sólo en tabletas o cápsulas)

c. Proteína (Barra o bebida)

d. Aminoácido

e. Bebidas energizantes (Ej. Ciclón, Redbull, Rockstar)

f. Bebidas deportivas (Ej. Gatorade, Powerade)

g. Vitaminas

h. Otros: _____________________

i. Ninguno

j. No sé



2. ¿Con qué frecuencia utilizas estos suplementos?



3. ¿Por qué has utilizado estos suplementos?

_____a. Mejorar mi rendimiento/ejecución

_____b. Evitar una lesión

_____c. Prevenir enfermarme

_____d. Mejorar cómo me veo físicamente

_____e. Por recomendación de una persona de confianza

_____f. Alguna otra razón: _________________________________

_____g. No utilizo suplementos

_____h. No sé



4. ¿Cuál es tu fuente de información para el uso de estos suplementos? (Marque solo uno)

_____a. Familia

_____b. Entrenador

_____c. Amigos

_____d. Médico

_____e. Terapista físico

_____f. Farmacéutico

_____g. Nutricionista

_____h. Yo mismo (Internet, revistas, libros, TV...)



5.¿Quién te consigue los suplementos?

_____a. Familia

_____b. Entrenador

_____c. Amigos

_____d. Yo mismo

_____e. Otro: ____________________________



6. ¿Dónde consigues estos suplementos?

_____a. Farmacia

_____b. Supermercado

_____c. GNC, Vitamin World)

_____d. Escuela

_____e. No sé

_____f. Otro lugar: ____________________________



7. Entiendo que sé mucho de suplementos nutricionales, sus usos, beneficios y riesgos.

_____a. Muy de acuerdo

_____b. De acuerdo

_____c. Neutral

_____d. En desacuerdo

_____e. Muy en desacuerdo



8. Usaría suplementos nutricionales con el fin de ser mejor en mi deporte.

_____a. Muy de acuerdo

_____b. De acuerdo

_____c. Neutral

_____d. En desacuerdo

_____e. Muy en desacuerdo



9. Pienso que el utilizar suplementos nutricionales no permitidos para poder llegar a las Olimpiadas está bien.

_____a. Muy de acuerdo

_____b. De acuerdo

_____c. Neutral

_____d. En desacuerdo

_____e. Muy en desacuerdo



10. Me interesa aprender más sobre los distintos suplementos nutricionales y su uso.

_____a. Muy de acuerdo

_____b. De acuerdo

_____c. Neutral

_____d. En desacuerdo

_____e. Muy en desacuerdo



Appendix 2

The survey must be answered only by the athlete/student.

Date _________________

Age _______________ years old

Gender F ____ M ____

Grade _____

Type of Sport: __________________________

1. What type of sport supplements have you used in the past 12 months? (Choose all that apply)

_____a. Creatina

_____b. Caffeine (only in tablets or capsules)

_____c. Protein (Bar or shake/drink)

_____d. Aminoacids

_____e. Energy Drinks (Ex. Ciclón, Redbull, Rockstar)

_____f. Sports drinks (Ex. Gatorade, Powerade)

_____g. Vitamines

_____h. Others: _____________________

_____i. None

_____j. Do not know



2. How frequently did you use these supplements?





3. Why did you use these supplements?

_____a. Improve my performance

_____b. Prevent an injury

_____c. Prevent illness

_____d. Improve my physical image

_____e. Someone I trusted recommended them

_____f. Another reason: _________________________________

_____g. I did not use supplements

_____h. Do not know



4. What was your primary source of information to use these supplements? (Choose only one)

_____a. Family

_____b. Trainer/Coach

_____c. Friends

_____d. Physician

_____e. Physical therapist

_____f. Pharmacist

_____g. Nutritionist

_____h. Myself (Internet, magazines, books, TV...)



5. Who gave you the supplements?

_____a. Family

_____b. Trainer/Coach

_____c. Friends

_____d. Myself

_____e. Other: ____________________________



6. Where do these supplements come from?

_____a. Pharmacy

_____b. Supermarket

_____c. Specialty stores (Ex: GNC, Vitamin World)

_____d. School

_____e. Do not know

_____f. Another place: ____________________________



7. I know a lot about sports supplements, their uses, benefits and risks.

_____a. Strongly Agree

_____b. Agree

_____c. Neutral

_____d. Disagree

_____e. Strongly Disagree



8. I would use these supplements in order to be better in my sport.

_____a. Strongly Agree

_____b. Agree

_____c. Neutral

_____d. Disagree

_____e. Strongly Disagree



9. I believe it is right to use banned sports supplements in order to participate in the Olympics.

_____a. Strongly Agree

_____b. Agree

_____c. Neutral

_____d. Disagree

_____e. Strongly Disagree



10. I am interested in learning more about sports supplements.

_____a. Strongly Agree

_____b. Agree

_____c. Neutral

_____d. Disagree

_____e. Strongly Disagree



 
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    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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