Prevalence Estimate of Blood Doping in Elite Track and Field Athletes During Two Major International Events

Self-Reported Use of Prohibited Substances and Methods Among Athletes of the Brazilian Delegations

ABSTRACT

Use of prohibited substances and methods (doping) by elite athletes is a complex and multifactorial behavior. Understanding the factors associated with doping behavior is crucial to identifying potential intervention targets to reduce doping among this group. However, there are limited data on the prevalence and correlations of self-reported prohibited substance use among Brazilian Olympic athletes. We present data from a cross-sectional, self-reported online survey. Participants were elite Brazilian athletes who participated in the 2020 Olympic and Paralympic Games. A total of 209 athletes (52.6% females) from both Brazilian delegations were surveyed. The self-reported doping use of prohibited substances or methods was found to be 7.2%. Receiving a recommendation from a medical doctor, even knowing that the substance is prohibited, was associated with an increased risk of self-reported doping use (OR = 17.474; 95% CI = 4.664-65.470, P < 0.001). Nearly 1 in 10 athletes reported use in their careers. Medical recommendation to use substances was the only factor associated with an increased risk of doping among elite athletes.

Insight on Exercise-Induced Heart Remodeling in Different Track and Field Disciplines

Background: The foot racing disciplines include sprints, middle distances, and long distances, which vary in terms of intensities, duration of training, and metabolic demands. The aim of our study was to evaluate the differences in morpho-functional parameters describing cardiac remodeling in a large cohort of Olympic athletes practicing the different track subspecialties. Methods: We evaluated 140 track and field (52.1% males, mean age 26.3 ± 4.3 years) Olympic athletes divided into four groups according to the distance performed: Group A (46, 32.9%): 100 and 200 mt; Group B (34, 24.3%): 400 mt; Group C (25, 17.9%): 800, 1500, and 3000 mt; Group D (35, 24.9%): 5000, 10,000 mt, and marathon distance. The athletes underwent a pre-participation screening, which included transthoracic echocardiography and exercise stress testing. Results: In Group A and in Group B, most athletes presented normal cardiac geometry (41/46, 89.1% in Group A and 31/34, 91.2% in Group B, p < 0.0001). Instead, in Groups C and D, more than half presented eccentric cardiac remodeling (13\25, 52% in Group C and 23\35, 65.7% in Group D). No significant differences were found between subspecialties in LVEF (p = 0.587), diastolic function (p = 0.431), and training hours/week (p = 0.078). Conclusions: In conclusion, the presence and extent of cardiac remodeling vary according to the distance of the discipline practiced, with the largest dimensional increase in both left and right ventricles and atria in mid- and long-distance runners and the lowest in sprinters.

Can the recent sex-specific evolutions in elite running performances be attributed to advanced footwear technology?

Recent improvements in elite running performances across all distances have been largely attributed to the introduction of advanced footwear technology (AFT), which features a curved and stiff plate working synergistically with a new generation of midsole foams demonstrating enhanced resilience and compliance. These recent improvements appear to be considerably more pronounced in women's events, highlighted by improvements in road racing world records by an average of 3.7% (range: 2.6%-5.2%) compared to mean progressions of 1.5% (range: 1.3%-1.9%) in the same men's events. Although there is a growing body of research investigating the mechanisms underpinning running performance enhancements derived from AFT, there remains no explanation for potential sex-based differences in their benefits. We overview the currently available evidence and highlight why the recent direction of AFT research provides a barrier to progress by focusing primarily on male athletes. We subsequently provide our perspective on why women may be benefiting from the new generation of shoes more than men, suggest potential mechanisms leading to hypotheses that need to be further investigated in upcoming studies, and finally propose that factors outside of footwear innovation may have concurrently driven the recently observed performance evolutions.

Prevalence of Drug Use in Ultraendurance Athletes

PURPOSE

In competitive sport, classic methods of measuring drug prevalence, such as doping controls or questionnaires, are challenging. Here we describe a novel urine sampling method to measure drug use in athletes. We hypothesize that the prevalence of drug use in ultramarathon runners is measured more accurately with our sampling method than randomized-response questionnaires.

METHODS

Urine samples and associated demographic data were collected from male participants using blind, automated urinals at the start of ultramarathon races. Various nonprohibited and prohibited substances were subsequently screened. Concomitantly, 2931 male and female runners participating in the same ultramarathons completed an anonymized, randomized-response questionnaire regarding drug use.

RESULTS

Among 412 individual urine samples, 205 (49.8%) contained at least one substance, and 16.3% of the samples contained one or more prohibited substances. Substances detected in urine included nonsteroid anti-inflammatory drugs (NSAID) (22.1%), acetaminophen (15.5%), opioids (6.6%), diuretics (4.9%), hypnotics (4.4%), glucocorticoids (2.7%), beta-2 agonists (2.2%), cannabinoids (1.9%), and stimulants (1.2%). None of the samples contained erythropoietin-receptor agonists or suspicious testosterone. Drug use was not associated with the participants' characteristics or ranking. Respondents to the questionnaire reported using acetaminophen (13.6%) and NSAID (12.9%); however, no prohibited substances were declared.

CONCLUSIONS

There was a high prevalence of drug use among male ultramarathon runners, in particular, NSAID and painkillers; however, performance-enhancing drugs were marginally used. Blind urine sampling highlighted prohibited drug use not declared in questionnaires, and it is useful to assess the prevalence of drug use and/or doping in competitive athletes.

Competitive performance as a discriminator of doping status in elite athletes

As the aim of any doping regime is to improve sporting performance, it has been suggested that analysis of athlete competitive results might be informative in identifying those at greater risk of doping. This research study aimed to investigate the utility of a statistical performance model to discriminate between athletes who have a previous anti-doping rule violation (ADRV) and those who do not. We analysed performances of male and female 100 and 800 m runners obtained from the World Athletics database using a Bayesian spline model. Measures of unusual improvement in performance were quantified by comparing the yearly change in athlete's performance (delta excess performance) to quantiles of performance in their age-matched peers from the database population. The discriminative ability of these measures was investigated using the area under the ROC curve (AUC) with the 55%, 75% and 90% quantiles of the population performance. The highest AUC values across age were identified for the model with a 75% quantile (AUC = 0.78-0.80). The results of this study demonstrate that delta excess performance was able to discriminate between athletes with and without ADRVs and therefore could be used to assist in the risk stratification of athletes for anti-doping purposes.

The potential impact of advanced footwear technology on the recent evolution of elite sprint performances

Background

Elite track and field sprint performances have reached a point of stability as we near the limits of human physiology, and further significant improvements may require technological intervention. Following the widely reported performance benefits of new advanced footwear technology (AFT) in road-running events, similar innovations have since been applied to sprint spikes in hope of providing similar performance enhancing benefits. However, it is not yet clear based on current evidence whether there have been subsequent improvements in sprint performance. Therefore, the aims of this study were to establish if there have been recent year-to-year improvements in the times of the annual top 100 and top 20 athletes in the men's and women's sprint events, and to establish if there is an association between the extensive use of AFT and potential recent improvements in sprint performances.

Methods

For the years 2016-19 and 2021-2022, the season best performances of the top 100 athletes in each sprint event were extracted from the World Athletics Top lists. Independent t-tests with Holm corrections were performed using the season's best performance of the top 100 and top 20 athletes in each year to identify significant differences between years for each sprint discipline. Following the classification of shoes worn by the top 20 athletes in each event during their annual best race (AFT or non-AFT), separate linear mixed-model regressions were performed to determine the influence of AFT on performance times.

Results

For the top 100 and top 20 athletes, there were no significant differences year-to-year in any sprint event prior to the release of AFT (2016-2019). There were significant differences between AFT years (2021 or 2022) and pre-AFT years (2016-2019) in eight out of 10 events. These differences ranged from a 0.40% improvement (men's 100 m) to a 1.52% improvement (women's 400 m hurdles). In the second analysis, multiple linear mixed model regressions revealed that the use of AFT was associated with improved performance in six out of ten events, including the men's and women's 100 m, women's 200 m, men's 110 m hurdles, women's 100 m hurdles and women's 400 m hurdles (estimate range: -0.037 - 0.521, p = <0.001 - 0.021). Across both analyses, improvements were more pronounced in women's sprint events than men's sprint events.

Conclusion

Following a period of stability, there were significant improvements in most sprint events which may be partly explained by advances in footwear technology. These improvements appear to be mediated by event, sex and potentially level of athlete.

Changes in Immature Reticulocytes Aid the Indirect Detection of Microdose Recombinant Erythropoietin Use in Men and Women

PURPOSE

We investigated whether immature reticulocyte fraction (IRF) and the immature reticulocytes to red blood cells ratio (IR/RBC) are sensitive and specific biomarkers for microdose recombinant human erythropoietin (rHuEPO) and whether the inclusion of reticulocyte percentage (RET%) and the algorithm "abnormal blood profile score (ABPS)" increased the athlete biological passport (ABP) sensitivity compared with hemoglobin concentration ([Hb]) and the OFF-hr score ([Hb]-60 × √RET%).

METHODS

Forty-eight (♀ = 24, ♂ = 24) participants completed a 2-wk baseline period followed by a 4-wk intervention period with three weekly intravenous injections of 9 IU·kg -1 ·bw -1 epoetin β (♀ = 12, ♂ = 12) or saline (0.9% NaCl, ♀ = 12, ♂ = 12) and a 10-d follow-up. Blood samples were collected weekly during baseline and intervention as well as 3, 5, and 10 d after treatment.

RESULTS

The rHuEPO treatment increased [Hb] (time-treatment, P < 0.001), RET% (time-treatment, P < 0.001), IRF (time-treatment, P < 0.001) and IR/RBC (time-treatment, P < 0.001). IRF and IR/RBC were up to ~58% ( P < 0.001) and ~141% ( P < 0.001) higher compared with placebo, and calculated thresholds provided a peak sensitivity across timepoints of 58% and 54% with ~98% specificity, respectively. To achieve >99% specificity for IRF and IR/RBC, sensitivity was reduced to 46% and 50%, respectively. Across all timepoints, the addition of RET% and ABPS to the ABP increased sensitivity from 29% to 46%. Identification of true-positive outliers obtained via the ABP and IRF and IR/RBC increased sensitivity across all timepoints to 79%.

CONCLUSIONS

In summary, IRF, IR/RBC, RET% and ABPS are sensitive and specific biomarkers for microdose rHuEPO in both men and women and complement the ABP.

Microdoses of Recombinant Human Erythropoietin Enhance Time Trial Performance in Trained Males and Females

PURPOSE

We investigated the effects of recombinant human erythropoietin (rHuEPO) administration on exercise endurance, maximal aerobic performance, and total hemoglobin mass (tHb). We hypothesized that frequent, small intravenous injections of epoetin β would increase time trial performance, peak oxygen uptake (V̇O 2peak ), and tHb in both males and females.

METHODS

We included 48 healthy, recreational to trained males ( n = 24, mean ± SD V̇O 2peak = 55 ± 5 mL O 2 ·kg -1 ⋅min -1 ) and females ( n = 24; V̇O 2peak of 46 ± 4 mL O 2 ·kg -1 ⋅min -1 ) in a counterbalanced, double-blind, randomized, placebo-controlled study design stratified by sex. Time trial performance, V̇O 2peak , and tHb were determined before and after intravenous injections of either rHuEPO (9 IU·kg bw -1 epoetin β) or saline (0.9% NaCl) three times weekly for 4 wk.

RESULTS

A time-treatment effect ( P < 0.05) existed for time trial performance. Within the rHuEPO group, mean power output increased by 4.1% ± 4.2% ( P < 0.001). Likewise, a time-treatment effect ( P < 0.001) existed for V̇O 2peak , where the rHuEPO group improved V̇O 2peak and peak aerobic power by 4.2% ± 6.1% ( P < 0.001) and 2.9% ± 4.0% ( P < 0.01), respectively. A time-treatment effect ( P < 0.001) existed for tHb, where the rHuEPO group increased tHb by 6.7% ± 3.4% ( P < 0.001). A main effect of "sex" alone was also evident ( P < 0.001), but no sex-specific interactions were found. No changes were observed in the placebo group for mean power output, V̇O 2peak , peak aerobic power, or tHb.

CONCLUSIONS

Microdoses with intravenous rHuEPO provide a sufficient erythropoietic stimuli to augment tHb and enhance aerobic-dominated performance in both trained males and females.

Hidden figures: Revisiting doping prevalence estimates previously reported for two major international sport events in the context of further empirical evidence and the extant literature

Background

High levels of admitted doping use (43.6% and 57.1%) were reported for two international sport events in 2011. Because these are frequently referenced in evaluating aspects of anti-doping, having high level of confidence in these estimates is paramount.

Objectives

In this study, we present new prevalence estimates from a concurrently administered method, the Single Sample Count (SSC), and critically review the two sets of estimates in the context of other doping prevalence estimates.

Methods

The survey featuring the SSC model was completed by 1,203 athletes at the 2011 World Championships in Athletics (WCA) (65.3% of all participating athletes) and 954 athletes at the 2011 Pan-Arab Games (PAG) (28.2% of all participating athletes). At WCA, athletes completed both UQM and SSC surveys in randomised order. At PAG, athletes were randomly allocated to one of the two surveys. Doping was defined as "having knowingly violated anti-doping regulations by using a prohibited substance or method."

Results

Estimates with the SSC model for 12-month doping prevalence were 21.2% (95% CI: 9.69-32.7) at WCA and 10.6% (95% CI: 1.76-19.4) at PAG. Estimated herbal, mineral, and/or vitamin supplements use was 8.57% (95% CI: 1.3-16.11) at PAG. Reliability of the estimates were confirmed with re-sampling method (n = 1,000, 80% of the sample). Survey non-compliance (31.90%, 95%CI: 26.28-37.52; p < 0.0001) was detected in the WCA data but occurred to a lesser degree at PAG (9.85%, 95% CI: 4.01-15.69, p = 0.0144 and 11.43%, 95% CI: 5.31-11.55, p = 0.0196, for doping and nutritional supplement use, respectively). A large discrepancy between those previously reported from the UQM and the prevalence rate estimated by the SSC model for the same population is evident.

Conclusion

Caution in interpreting these estimates as bona fide prevalence rates is warranted. Critical appraisal of the obtained prevalence rates and triangulation with other sources are recommended over "the higher rate must be closer to the truth" heuristics. Non-compliance appears to be the Achilles heel of the indirect estimation models thus it should be routinely tested for and minimised. Further research into cognitive and behaviour aspects, including motivation for honesty, is needed to improve the ecological validity of the estimated prevalence rates.

The Training Characteristics of World-Class Distance Runners: An Integration of Scientific Literature and Results-Proven Practice

In this review we integrate the scientific literature and results-proven practice and outline a novel framework for understanding the training and development of elite long-distance performance. Herein, we describe how fundamental training characteristics and well-known training principles are applied. World-leading track runners (i.e., 5000 and 10,000 m) and marathon specialists participate in 9 ± 3 and 6 ± 2 (mean ± SD) annual competitions, respectively. The weekly running distance in the mid-preparation period is in the range 160–220 km for marathoners and 130–190 km for track runners. These differences are mainly explained by more running kilometers on each session for marathon runners. Both groups perform 11–14 sessions per week, and ≥ 80% of the total running volume is performed at low intensity throughout the training year. The training intensity distribution vary across mesocycles and differ between marathon and track runners, but common for both groups is that volume of race-pace running increases as the main competition approaches. The tapering process starts 7–10 days prior to the main competition. While the African runners live and train at high altitude (2000–2500 m above sea level) most of the year, most lowland athletes apply relatively long altitude camps during the preparation period. Overall, this review offers unique insights into the training characteristics of world-class distance runners by integrating scientific literature and results-proven practice, providing a point of departure for future studies related to the training and development in the Olympic long-distance events.

Ten years of collecting hematological athlete biological passport samples—perspectives from a National Anti-doping Organization

The hematological module of the Athlete Biological Passport (ABP) aims to reveal blood doping indirectly by looking at selected biomarkers of doping over time. For Anti-Doping Organizations (ADOs), the ABP is a vital tool in the fight against doping in sports through improved target testing and analysis, investigations, deterrence, and as indirect evidence for use of prohibited methods or substances. The physiological characteristics of sport disciplines is an important risk factor in the overall risk assessment and when implementing the hematological module. Sharing of experiences with implementing the hematological ABP between ADOs is key to further strengthen and extend its use. In this study, we present 10 years of experience with the hematological ABP program from the perspectives of a National ADO with special attention to sport disciplines' physiological characteristics as a potential risk factor for blood doping. Not surprisingly, most samples were collected in sport disciplines where the aerobic capacity is vital for performance. The study highlights strengths in Anti-Doping Norway's testing program but also areas that could be improved. For example, it was shown that samples were collected both in and out of season in a subset of the data material that included three popular sports in Norway (Cross-Country Skiing, Nordic Combined, and Biathlon), however, from the total data material it was clear that athletes were more likely to be tested out of competition and on certain days of the week and times of the day. The use of doping control officers with a flexible time schedule and testing outside an athlete's 60 min time-slot could help with a more even distribution during the week and day, and thus reduce the predictability of testing. In addition to promoting a discussion on testing strategies, the study can be used as a starting point for other ADOs on how to examine their own testing program.

A quantitative approach for mathematical model of doping in high performance sport

Doping or administration of substances for purpose of improving the performances in various sport has a long history, even in the modern era to most common association of doping is connected to professional cycling. The usage of doping substances has become a major public health issue. Also, some abuse of doping substance was a major cause of death in some cases. As results of effort in fighting against doping, World Anti-Doping Agency (WADA) coordinated the implementation of the athlete hematological passport, or more commonly athlete biological passport (ABP). The decision of doped or not doped based on biological markers is made using Bayesian inference. But the code of implementation and the code of software used in decisions is not available to the public, and as sequels there are also some approaches in research, as methods based on psychological questionaries. In this case, the statistical analysis using structural equation models offer a valuable tool for management of antidoping policies in order to reduce this phenomenon. Material and method. In this paper, a novel method is novel model for quantitative analysis of doping is proposed. The model doesn’t use the biological markers but the effect of this as declared doping persons in a quantitative analysis over a lot of high performance athletes. The model is based on nonlinear equations as result of compartmental model with quantitative time dependent evolution of them. Results and discussions. The model was implemented in MATLAB and numerical solutions were obtained using ODE (Ordinary Differential Equations) tool. The stability of model was analyzed using analogies with an epidemic SIRS compartmental model. The implementation uses a GUI (Graphical User Interface) that make the application user friendly. The fitting tools model is in stage of implementation and the parameter are finding out using a data collected and optimization tools (an objective function and genetic algorithms in order to prevent the phenomenon in a trapping minima). Conclusions. The result is very encouraging, the model fit 99.7% in preliminary set of data. The future development will include the fitting module and a set of results structured on various high-performance sports. Keywords: doping in sport, compartmental models, anti-doping policy, modeling and simulation, data fit-ting

Autologous Blood Doping Induced Changes in Red Blood Cell Rheologic Parameters, RBC Age Distribution, and Performance

Simple Summary

Autologous blood doping (ABD) refers to the artificial increase in circulating red blood cell (RBC) mass by sampling, storage, and transfusion of one’s own blood. It is assumed that some athletes apply this prohibited technique to improve oxygen transport capacity and thus exercise performance. The primary aim of this study was to test whether RBC rheological and associated parameters significantly change due to ABD with the consideration of whether this type of measurement might be suitable for detecting ABD. Further, it was assessed whether those changes are translated into indices of endurance performance. Eight males underwent an ABD protocol combined with several blood parameter measurements and two exercise tests (pre and post transfusion). Results of this investigation suggest a change in the distribution of age-related RBC sub-populations and altered deformability of total RBC as well as of the respective sub-populations. Further, the identified changes in RBC also appear to improve sports performance. In conclusion, these data demonstrate significant changes in hematological and hemorheological parameters, which could be of interest in the context of new methods for ABD detection. However, additional research is needed with larger and more diverse study groups to widen the knowledge gained by this study.

Abstract

Autologous blood doping (ABD) refers to the transfusion of one’s own blood after it has been stored. Although its application is prohibited in sports, it is assumed that ABD is applied by a variety of athletes because of its benefits on exercise performance and the fact that it is not detectable so far. Therefore, this study aims at identifying changes in hematological and hemorheological parameters during the whole course of ABD procedure and to relate those changes to exercise performance. Eight healthy men conducted a 31-week ABD protocol including two blood donations and the transfusion of their own stored RBC volume corresponding to 7.7% of total blood volume. Longitudinal blood and rheological parameter measurements and analyses of RBC membrane proteins and electrolyte levels were performed. Thereby, responses of RBC sub-populations—young to old RBC—were detected. Finally, exercise tests were carried out before and after transfusion. Results indicate a higher percentage of young RBC, altered RBC deformability and electrolyte concentration due to ABD. In contrast, RBC membrane proteins remained unaffected. Running economy improved after blood transfusion. Thus, close analysis of RBC variables related to ABD detection seems feasible but should be verified in further more-detailed studies.

The effects of the COVID-19 pandemic on the use of the performance-enhancing drugs

The coronavirus disease (COVID-19) pandemic has been impacting the whole society in every aspect of the daily life, comprising the sport field. Several restrictive strategies have been implemented by governments in an effort to stem the spread of the disease and salvage public health. Such efforts have severely constrained access to non-essential services, leading to the closure of non-essential points of gathering and business and the enforcement of rigorous social distancing and prolonged lockdowns, in addition to masking and stay-at-home mandates. However necessary, there is no denying that such extremely rigorous, and to most people unprecedented, measures have adversely affected the global economy and the daily lives of everyone of us, including professional and amateur athletes (1). The most important sport events were postponed or cancelled, including the 2020 Tokyo Olympic Games. But how was the phenomenon of performance-enhancing drug (PED) use impacted and how was the most concerning issue affecting the integrity of sport affected by the pandemic control restrictions? The World Anti-doping Agency (WADA) was established in 1999, whereas its code was implemented in 2004 in order to articulate and enforce doping control initiatives and provide educational strategies aimed at preventing PED use (2). Nonetheless, it is worth noting that the prevalence of PED use among athletes is mostly unchanged since the foundation of WADA. Unfortunately, the use of the performance-enhancing drugs is not limited to athletic performances, but it concerns other settings as well. Nowadays, several strategies for doping control are adopted such as education, deterrence, detection, enforcement and rule of law (3), but the most important anti-dissemination strategy is constituted by information campaigns, especially addressed to youngsters, meant to raise awareness as to the serious health risks involved in PED use. Currently, the primary drivers of anabolic androgenic steroids (ASA) use are 1) the determination to improve performances and prevail no matter what the cost may be; 2) the economic benefits, popularity and fame; 3) greater stamina and resistance. This public health issue has raised particular concerns due to the recent ASA market developments, which is somewhat similar to the illicit market of narcotic drugs. Moreover, it has to be considered that the higher stress and psychosocial condition related to pandemic social restrictions has fueled and exacerbated substance use disorders (4). The prevalence of doping in sport causes unfairness and damages the very fabric of our society, especially insofar as it involves children and young adults who look up to athletes as role models. In this concern, the impact of the COVD-19 pandemic may have led to substantial modifications in substance use patterns and an increased risk of substitution, adulteration, contamination, and dilution with a potentially harmful substance (5, 6). During the COVID-19 lockdown, WADA and stakeholders suspended or scaled down doping control programs, testing and other activities. As a consequence, athletes have seen the unexpected opportunity to misuse AAS without the possible risk of testing positive (7). This has been controversial, considering the measures taken by governments to flatten the pandemic curve in order to safeguard public health. Indeed, all the technologies implemented for teleworking, such as teaching students on-line, telehealth applications, prescriptions and referrals, and treating patients in hospitals/care homes via video links can also be applied to enhance and uphold sport integrity. Conversely, anti-doping testing for professional competitive athletes has increased, due to the lockdown raising suspicion about doping opportunities. The U.S. Anti-doping Agency has put in place novel measures to combat the lack of anti-doping testing during the pandemic: these include a "in-home self-test" that requires athletes to provide urine and small blood samples at home to be tested in the anti-doping laboratory, under supervision provided by video-conference (8). As such, reports from forensic science and toxicology laboratories are crucial for the early detection and response to such events. Furthermore, toxicology laboratories should assure their continue effort in providing new methods and technologies designed to tackle the consumption of illicit substances and to monitor the constantly changing illegal drug markets (9). The most recent WADA code revision has certainly brought about important progress in the ongoing fight against PED abuse. Indeed, it has introduced the possibility to store the samples for 10 years after the first analysis, maintaining the same legal value if re-tested and use for prosecution purposes (10). In that regard, the prospect of re-testing the same sample with newly developed analytical methods based on innovative technologies may represent a strong deterrent for doping users, since anti-doping research rapidly evolves (6), largely by implementing the same approaches used to fight new psychoactive substances (NPS) use (11,12). It is worth noting that the NPS phenomenon bears several similarities with doping, especially due to the constant emergence of new substances and methods aimed at circumventing current legal restrictions. In Italy, the National Antidoping Organization (NADO-Italia) is in charge of guaranteeing compliance with WADA rules and the transposition of the List of Prohibited Substances and Methods. However, the gap between elite athletes and amateur athletes is still broad and unaddressed, since non-professional sport competitions are not adequately overseen, and neither are the competing athletes . This difference may give rise to an important public health issue, on account of the adverse effects of uncontrolled doping agents consumption. In this concern, the Italian anti-doping law created the "Section of the Technical Health Committee for Supervision and Control on Doping and for Health Protection in Sport Activities", that carries out, among its other tasks, the following activities on amateur sport: 1) updating each year the list of banned substances and practices, adapting it to the WADA list; 2) determining cases, criteria and methodologies for anti-doping controls; 3) promoting research projects and information/training campaigns meant to protect health in sports and tackle doping (13). In conclusion, regarding the highly complex dynamics triggered by the pandemic, new and unexpected challenges have come to the fore in the ongoing fight against substance abuse in its every aspect, such as NPS (14), ASA consumption by amateur athletes, or other substance abuse settings, e.g. driving under the influence of psychotropic substances (15). The current Italian antidoping approach for amateur athletes seems to be a promising strategy to bridge the gap between professional sports and amateur sports. Moreover, youngsters should be thoroughly educated as to the threats posed by such substances, so that they can realize how profoundly and severely drug abuse can affect not only their sport career, but their health and well-being overall.

Removal of the influence of plasma volume fluctuations for the athlete biological passport and stability of haematological variables in active women taking oral contraception

The haematological module of the athlete biological passport (ABP) monitors longitudinal haematological variations that could be indicative of blood manipulation. This study applied a multi‐parametric model previously validated in elite cyclists to compare inferred and actual PV variations, whereas the potential influence of the oral contraceptive pill (OCP) cycle on the ABP blood biomarkers and plasma volume (PV) in 14 physically active women taking OCPs was also investigated. Blood and serum samples were collected each week for 8 weeks, and the ABP haematological variables were determined according to the World Anti‐Doping Agency guidelines. Transferrin (sTFN), ferritin (FERR), albumin (ALB), calcium (Ca), creatinine (CRE), total protein (TP) and low‐density lipoprotein (LDL) were additionally computed as ‘volume‐sensitive’ variables in a multivariate analysis to determine individual estimations of PV variations. Actual PV variations were indirectly measured using a validated carbon monoxide rebreathing method. We hypothesised ABP markers to be stable during a standard OCP cycle and estimated PV variations similar to measured PV variations. Measured PV variations were in good agreement with the predictions and allowed to explain an atypical passport finding (ATPF). The ABP biomarkers, Hbmass and PV were stable over 8 weeks. Significant differences occurred only between Week 7 and Week 1, with lower levels of haemoglobin concentration ([Hb]), haematocrit (HCT) and red blood cell count (RBC)(−4.4%, p < 0.01; −5.1%, p < 0.01; −5.2%, p < 0.01) and higher levels of PV at week 7 (+9%, p = 0.05). We thus concluded that estimating PV variations may help interpret individual ABP haematological profiles in women.

Integrating Whole Blood Transcriptomic Collection Procedures Into the Current Anti-Doping Testing System, Including Long-Term Storage and Re-Testing of Anti-Doping Samples

Introduction: Recombinant human erythropoietin (rHuEPO) administration studies involving transcriptomic approaches have demonstrated a gene expression signature that could aid blood doping detection. However, current anti-doping testing does not involve collecting whole blood into tubes with RNA preservative. This study investigated if whole blood in long-term storage and whole blood left over from standard hematological testing in short-term storage could be used for transcriptomic analysis despite lacking RNA preservation.

Methods: Whole blood samples were collected from twelve and fourteen healthy nonathletic males, for long-term and short-term storage experiments. Long-term storage involved whole blood collected into Tempus™ tubes and K₂EDTA tubes and subjected to long-term (i.e., ‒80°C) storage and RNA extracted. Short-term storage involved whole blood collected into K₂EDTA tubes and stored at 4°C for 6‒48 h and then incubated at room temperature for 1 and 2 h prior to addition of RNA preservative. RNA quantity, purity, and integrity were analyzed in addition to RNA-Seq using the MGI DNBSEQ-G400 on RNA from both the short- and long-term storage studies. Genes presenting a fold change (FC) of >1.1 or < ‒1.1 with p ≤ 0.05 for each comparison were considered differentially expressed. Microarray analysis using the Affymetrix GeneChip® Human Transcriptome 2.0 Array was additionally conducted on RNA from the short-term study with a false discovery ratio (FDR) of ≤0.05 and an FC of >1.1 or < ‒1.1 applied to identify differentially expressed genes.

Results: RNA quantity, purity, and integrity from whole blood subjected to short- and long-term storage were sufficient for gene expression analysis. Long-term storage: when comparing blood tubes with and without RNA preservation 4,058 transcripts (6% of coding and non-coding transcripts) were differentially expressed using microarray and 658 genes (3.4% of mapped genes) were differentially expressed using RNA-Seq. Short-term storage: mean RNA integrity and yield were not significantly different at any of the time points. RNA-Seq analysis revealed a very small number of differentially expressed genes (70 or 1.37% of mapped genes) when comparing samples stored between 6 and 48 h without RNA preservative. None of the genes previously identified in rHuEPO administration studies were differently expressed in either long- or short-term storage experiments.

Conclusion: RNA quantity, purity, and integrity were not significantly compromised from short- or long-term storage in blood storage tubes lacking RNA stabilization, indicating that transcriptomic analysis could be conducted using anti-doping samples collected or biobanked without RNA preservation.

Anti-doping and other sport integrity challenges during the COVID-19 pandemic

The coronavirus disease (COVID-19) pandemic has had an unprecedent impact on the world of sport and society at large. Many of the challenges with respect to integrity previously facing competitive sport have been accentuated further during the pandemic. Threats to the integrity of sporting competition include traditional doping, issues of technological fairness, and integration of transgender and intersex athletes in elite sport. The enforced lull in competitive sport provides an unprecedented opportunity for stakeholders in sport to focus on unresolved integrity issues and develop and implement long-lasting solutions. There needs to be a concerted effort to focus on the many technological innovations accelerated by and perfected during COVID-19 that have enabled us to work from home, such as teaching students on-line, applications for medical advice, prescriptions and referrals, and treating patients in hospitals/care homes via video links and use these developments and innovations to enhance sport integrity and anti-doping procedures. Positive sports integrity actions will require a considered application of all such technology, as well as the inclusion of "omics" technology, big data, bioinformatics and machine learning/artificial intelligence approaches to modernize sport. Applications include protecting the health of athletes, considered non-discriminative integration of athletes into elite sport, intelligent remote testing to improve the frequency of anti-doping tests, detection windows, and the potential combination with omics technology to improve the tests' sensitivity and specificity in order to protect clean athletes and deter doping practices.

Racing Clean in a Tainted World: A Qualitative Exploration of the Experiences and Views of Clean British Elite Distance Runners on Doping and Anti-Doping

Background: Doping has been a prominent issue for the sport of athletics in recent years. The endurance disciplines, which currently account for 56% of the global anti-doping rule violations in athletics, appear to be particularly high risk for doping. Objective: Using this high-risk, high-pressure context, the main purpose of this study was to investigate the human impact of doping and anti-doping on "clean" athletes. The secondary aim of the study was to better understand the reasons for, and barriers to, competing "clean" among this group of athletes. Method: Semi-structured interviews were conducted with 11 elite distance runners from the UK to explore: (1) the reasons and motivations for competing clean. (2) Perceptions of the anti-doping system, and experiences of being part of that system. (3) Views on the prevalence and causes of doping and the impact of doping on the lives of clean athletes. The interviews were audio-recorded, transcribed verbatim, and analysed using Reflexive Thematic Analysis. Results: Four major themes were identified: (1) The participants in this study have not been tempted to use prohibited substances or methods; they compete in their sport for the personal satisfaction of seeing how good they can be, rather than in pursuit of winning at all costs. (2) Anti-doping does not currently prevent doping effectively and is not implemented evenly across the globe. (3) Doping was perceived as a major issue and was felt to be borne out of certain sporting cultures in which doping is enabled. (4) Doping has impacted the careers of clean athletes in irreversible ways and presents a continuing challenge to the psychological preparation for competition. Conclusions: Clean athletes suffer negative consequences from both doping and anti-doping. ADOs must collaborate across borders to ensure a more even implementation of anti-doping activities, to facilitate a more level playing field on the global stage. ADOs must also acknowledge the existence of a large group of athletes who would never consider deliberately doping and make anti-doping work for these athletes too.

Doping Prevalence in Competitive Sport: Evidence Synthesis with "Best Practice" Recommendations and Reporting Guidelines from the WADA Working Group on Doping Prevalence

BACKGROUND

The prevalence of doping in competitive sport, and the methods for assessing prevalence, remain poorly understood. This reduces the ability of researchers, governments, and sporting organizations to determine the extent of doping behavior and the impacts of anti-doping strategies.

OBJECTIVES

The primary aim of this subject-wide systematic review was to collate and synthesize evidence on doping prevalence from published scientific papers. Secondary aims involved reviewing the reporting accuracy and data quality as evidence for doping behavior to (1) develop quality and bias assessment criteria to facilitate future systematic reviews; and (2) establish recommendations for reporting future research on doping behavior in competitive sports to facilitate better meta-analyses of doping behavior.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to identify relevant studies. Articles were included if they contained information on doping prevalence of any kind in competitive sport, regardless of the methodology and without time limit. Through an iterative process, we simultaneously developed a set of assessment criteria; and used these to assess the studies for data quality on doping prevalence, potential bias and reporting.

RESULTS

One-hundred and five studies, published between 1975 and 2019,were included. Doping prevalence rates in competitive sport ranged from 0 to 73% for doping behavior with most falling under 5%. To determine prevalence, 89 studies used self-reported survey data (SRP) and 17 used sample analysis data (SAP) to produce evidence for doping prevalence (one study used both SRP and SAP). In total, studies reporting athletes totaled 102,515 participants, (72.8% men and 27.2% women). Studies surveyed athletes in 35 countries with 26 involving athletes in the United States, while 12 studies examined an international population. Studies also surveyed athletes from most international sport federations and major professional sports and examined international, national, and sub-elite level athletes, including youth, masters, amateur, club, and university level athletes. However, inconsistencies in data reporting prevented meta-analysis for sport, gender, region, or competition level. Qualitative syntheses were possible and provided for study type, gender, and geographical region. The quality assessment of prevalence evidence in the studies identified 20 as "High", 60 as "Moderate", and 25 as "Low." Of the 89 studies using SRP, 17 rated as "High", 52 rated as "Moderate", and 20 rated as "Low." Of the 17 studies using SAP, 3 rated as "High", 9 rated as "Moderate", and 5 rated as "Low." Examining ratings by year suggests that both the quality and quantity of the evidence for doping prevalence in published studies are increasing.

CONCLUSIONS

Current knowledge about doping prevalence in competitive sport relies upon weak and disparate evidence. To address this, we offer a comprehensive set of assessment criteria for studies examining doping behavior data as evidence for doping prevalence. To facilitate future evidence syntheses and meta-analyses, we also put forward "best practice" recommendations and reporting guidelines that will improve evidence quality.

Co-creating a social science research agenda for clean sport: An international Delphi study

BACKGROUND

Doping in sport is a significant issue. To date, research informing doping prevention has lacked a framework guiding research priorities. To ensure research is coordinated, sustainable and focused on end-user priorities, this study co-created the first research agenda for doping prevention.

METHODS

The Delphi method was used to develop this agenda. Based upon two substantive reviews of the doping literature and 12 focus groups across five countries, a questionnaire was developed assessing the importance of 15 research topics and identifying research questions.  Eighty-two anti-doping stakeholders with relevant expertise were invited to be panel members. In Round 1, an expert panel (n = 57; 70% response rate) completed this questionnaire. In Round 2, panel members (n = 33; 58% response rate) ranked for relative importance the eight topic areas rated highest in Round 1, before doing the same for research questions within each topic. Based on these rankings, a draft agenda was created. In Round 3, panel members (n = 26; 79% response rate) rated the degree to which they accepted this agenda, the feasibility of its delivery and identified possible barriers and facilitators to implementation.

RESULTS

The results of Round 1 and Round 2 were used to create a draft agenda consisting of 18 research questions stratified across eight topic areas. This agenda was either fully (n = 16) or mostly (n = 9) accepted by the panel in Round 3 (96.2%). Research topics included the effectiveness of interventions/education programmes, environmental influences, long-term development of protective and risk factors in athletes and their entourage, athletes' experiences of anti-doping procedures and athletes' place in the anti-doping system.

CONCLUSIONS

A rigorous exercise created an agenda for doping prevention research. Adoption and application of this agenda should lead to better coordination, more efficient use of funding, enhanced uptake of research findings and more effective doping prevention education.

Annual banned-substance review: Analytical approaches in human sports drug testing 2019/2020

Analytical chemistry-based research in sports drug testing has been a dynamic endeavor for several decades, with technology-driven innovations continuously contributing to significant improvements in various regards including analytical sensitivity, comprehensiveness of target analytes, differentiation of natural/endogenous substances from structurally identical but synthetically derived compounds, assessment of alternative matrices for doping control purposes, and so forth. The resulting breadth of tools being investigated and developed by anti-doping researchers has allowed to substantially improve anti-doping programs and data interpretation in general. Additionally, these outcomes have been an extremely valuable pledge for routine doping controls during the unprecedented global health crisis that severely affected established sports drug testing strategies. In this edition of the annual banned-substance review, literature on recent developments in anti-doping published between October 2019 and September 2020 is summarized and discussed, particularly focusing on human doping controls and potential applications of new testing strategies to substances and methods of doping specified the World Anti-Doping Agency's 2020 Prohibited List.

'Clean athlete status' cannot be certified: Calling for caution, evidence and transparency in 'alternative' anti-doping systems

Athletes, sponsors and sport organisations all have a vested interest in upholding the values of clean sport. Despite the considerable and concerted efforts of the global anti-doping system over two decades, the present system is imperfect. Capitalising upon consequent frustrations of athletes, event organisers and sponsors, alternative anti-doping systems have emerged outside the global regulatory framework. The operating principles of these systems raise several concerns, notably including accountability, legitimacy and fairness to athletes. In this paper, we scrutinise the Clean Protocol™, which is the most comprehensive alternative system, for its shortcomings through detailed analysis of its alleged logical and scientific merits. Specifically, we draw the attention of the anti-doping community - including researchers and practitioners - to the potential pitfalls of using assessment tools beyond the scope for which they have been validated, and implementing new approaches without validation. Further, we argue that whilst protecting clean sport is critically important to all stakeholders, protocols that put athletes in disadvantageous positions and/or pose risks to their professional and personal lives lack legitimacy. We criticise the use of anti-doping data and scientific research out of context, and highlight unintended harms that are likely to arise from the widespread implementation of such protocols in parallel with - or in place of - the existing global anti-doping framework.

Refined Analysis of a Cross-Sectional Doping Survey Among Recreational Triathletes: Support for the Nutritional Supplement Gateway Hypothesis

Introduction: The current literature provides no consensus that nutritional supplements (NS) may provide a gateway to doping. In particular, studies in recreational athletes are lacking. Within a previous cross-sectional empirical study, our group provided first evidence that the use of NS may provide a gateway for the use of doping substances in recreational triathletes. For the present paper, we refine the analysis of the triathletes’ survey in order to provide evidence for a NS gateway hypothesis in recreational athletes.

Methods: A self-report, paper-and-pencil questionnaire was distributed to a sample of 2,997 competitive ironman and half-ironman (n = 1,076; 36.1%) triathletes. The randomized response technique (RRT) was used to assess the 12-month prevalence estimate for the use of doping substances. The prevalence for the use of NS was assessed by using direct questioning. Two-tailed (α = 0.05) large-sample z-tests were performed to assess whether the estimated prevalence for the use of doping substances differs significantly between users and nonusers of NS.

Results: The 12-month prevalence estimate for the use of doping substances is significantly higher in athletes who report using NS (20.6%) compared to those who do not (11.4%; z = 2.595, p = 0.0097).

Conclusion: The present results are consistent with the hypothesis that the use of NS provides a gateway to the use of doping substances. Therefore, doping prevention concepts should not primarily focus on preventing the use of doping substances per se, but should start one step earlier, namely by the use of NS.