Classification of middle- and long-distance runners based upon their performance

The scientific literature lacks consensus on classification of middle- and long-distance runners. This creates situations where the sample studied may not represent the target population and could produce misleading conclusions. Thus, we present an approach for a data-driven classification of middle- and long-distance runners according to their competition results. The best annual results of middle- and long-distance track runners participating at major (Olympics, World and European Championships) and national championships (Denmark, Sweden, Finland, Norway) were gathered for the 2012-2018 period. Overall, 1920 men's and 1808 women's performance results were gathered. The results were grouped accordingly. Quadratic discriminant analysis was applied to define the limits between the groups. Three basic categories could be proposed for classification: world class, international and national. Classification provides a realistic overview of performance standards and the number of athletes for different categories in middle- and long-distance track running in real-world settings. The performance-based classification provides data-driven and unified criteria for reporting standards on athletes' proficiency levels. It allows for more consistent reporting practices on the target population in research. In addition to scientific research, the classification could also be employed for a variety of practical purposes.

Medical services at the FIFA world cup Qatar 2022

OBJECTIVE

The Football World Cup is among the biggest sporting events in the world, but data to inform the requirements of medical care for such tournaments are limited. This study describes the athlete and team medical services at the FIFA World Cup Qatar 2022 .

METHODS

Three different medical service entities were identified through a needs analysis based on expert advice, team physician interviews and questionnaires prior to the event: 'Team Services' to provide any workforce or equipment needs of the teams, a 'Polyclinic' to manage any acute medical demands, and a 'recovery centre' to improve game readiness throughout the tournament. All services had been set up prior to the tournament and thoroughly tested.

RESULTS

Of a total of 832 athletes, ~1300 team delegation and ~130 match officials, 167 individuals including 129 (77%) athletes and 38 (23%) non-athletes were assessed in the polyclinic. For the 129 athletes (median 4 players per team), medical imaging was the most requested service, which peaked during the group phase of the tournament. Most requests were received during normal working hours despite many games finishing late at night. 30 of the 32 participating teams solicited medical services for their players at least once. Three teams made use of the recovery facilities, and 17 teams requested additional medical equipment or clinical assistance.

CONCLUSION

Central imaging services was the most used medical resource at the FIFA World Cup Qatar 2022, and over half of teams required additional medical equipment or personnel. These data may inform planning of medical services for similar events in the future.

Impact of COVID-19 lockdown on injury risk in Qatar's professional football

OBJECTIVES

To compare injury incidence, burden and characteristics between the pre- and post-COVID-19 lockdown periods in Qatari professional football.

DESIGN

Prospective cohort study.

METHODS

Injury and exposure data for two post-COVID-19 lockdown periods [early post-lockdown period: short-term ~2 months (54 matches) and late post-lockdown period: long-term 8-months (183 matches)] were compared to the benchmark of the same periods from the three previous seasons (2017/18-2019/20).

RESULTS

We observed no difference in overall, training or match incidence between early post-lockdown period and the benchmark reference. However, this short-term period resulted in lower burden for overall- (RR 0.80, P < 0.0001), training- (RR 0.73, P < 0.0001) and match-injuries (RR 0.40, P < 0.0001) compared to the benchmark. During late post-lockdown period match injury incidence (RR 0.72, P = 0.0010) and match injury burden (RR 0.69, P < 0.001) were lower than the benchmark. In contrast, both overall- (RR 1.30, P < 0.001) and training-injury burden (RR 1.65, P < 0.001) were higher. A significant increase in adductor strains in both post-lockdown periods was observed.

CONCLUSIONS

Immediately after the COVID-19 lockdown (short-term effect), there was no difference in injury incidence but a lower injury burden compared to benchmark. Moreover, the rapid return to competition for the successive season (long-term effect) was associated with a higher overall- and training-injury burden, but a lower match-injury burden compared to the benchmark.

Imaging-detected sports injuries and imaging-guided interventions in athletes during the 2022 FIFA football (soccer) World Cup

OBJECTIVE

To describe imaging-detected musculoskeletal injuries and image-guided interventional procedures during the 2022 FIFA football (soccer) World Cup.

MATERIALS AND METHODS

Retrospective analysis of all radiologic examinations performed in a central medical facility for athletes was performed by two board certified musculoskeletal radiologists. Data on muscle, tendon, ligament, cartilage, and bone injuries were collected according to imaging modality and body part.

RESULTS

A total of 143 radiology examinations in 94 athletes were evaluated at the central medical facility. Magnetic resonance imaging (MRI) was the most utilized modality (67%), followed by radiography (12%), ultrasonography (9%), and computed tomography (4%). Image-guided interventions corresponded to 8% of all radiological examinations. There were 112 injuries described, affecting muscles and tendons (42%), ligaments (25%), cartilage (21%), and bone (12%). Most injured body parts were thigh (27%), foot and ankle (23%), knee (23%), and hip/groin (8%). Most injured players were within the age range of 24-35 years old (71%).

CONCLUSION

Imaging was utilized in 11% of players who participated in the 2022 FIFA World Cup in Qatar. MRI was the most utilized modality, and acute muscle tears were the most diagnosed type of injury. Diagnostic imaging played an important role in diagnosing sports-related injuries during the 2022 FIFA World Cup.

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 1: acute respiratory infections

Acute illnesses affecting the respiratory tract are common and form a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. Acute respiratory illness (ARill) can broadly be classified as non-infective ARill and acute respiratory infections (ARinf). The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to ARinf in athletes. The International Olympic Committee (IOC) Medical and Scientific Commission appointed an international consensus group to review ARill (non-infective ARill and ARinf) in athletes. Six subgroups of the IOC Consensus group were initially established to review the following key areas of ARill in athletes: (1) epidemiology/risk factors for ARill, (2) ARinf, (3) non-infective ARill including ARill due to environmental exposure, (4) acute asthma and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport and (6) acute nasal/vocal cord dysfunction presenting as ARill. Several systematic and narrative reviews were conducted by IOC consensus subgroups, and these then formed the basis of sections in the consensus documents. Drafting and internal review of sections were allocated to 'core' members of the consensus group, and an advanced draft of the consensus document was discussed during a meeting of the main consensus core group in Lausanne, Switzerland on 11 to 12 October 2021. Final edits were completed after the meeting. This consensus document (part 1) focusses on ARinf, which accounts for the majority of ARill in athletes. The first section of this consensus proposes a set of definitions and classifications of ARinf in athletes to standardise future data collection and reporting. The remainder of the consensus paper examines a wide range of clinical considerations related to ARinf in athletes: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations, risks of infection during exercise, effects of infection on exercise/sports performance and return-to-sport guidelines.

The athletic characteristics of Olympic sports to assist anti-doping strategies

The determinants of success in Olympic Games competition are specific to the athletic demands of the sporting event. A global evaluation to quantify the athletic demands across the spectrum of the Olympic Games sport events has not previously been conducted. Thus far, the interpretation and the comparison of sport physiological characteristics within anti-doping organisations (ADOs) risk assessments remains subjective without a standardised framework. Despite its subjective assessment, this information is a key component of any anti-doping programme. Sport characteristics inevitably influence the type of substances and/or methods used for doping purpose and should be captured through a comprehensive analysis. Seven applied sport scientists independently conducted an assessment to quantify the athletic demands across six preselected athletic variables. A Principal Component Analysis was performed on the results of the panel's quantitative assessment for 160 Olympic Sport events. Sport events were clustered using the Hierarchical Density Based Spatial Clustering of Applications with Noise (HDBSCAN) algorithm. The HDBSCAN identified 19 independent cluster groups, 36 sport events remained statistically unassigned to a cluster group representing unique and eventspecific athletic demands. This investigation provides guidance to the anti-doping community to assist in the development of the sport specific physiology component of the risk assessment for Olympic Games disciplines. The dominant athletic characteristics to excel in each of these individual events will highlight areas of how athletes may strive to gain a competitive advantage through doping strategies, and inform the development of an effective and proportionate allocation of testing resources.

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 2: non-infective acute respiratory illness

Acute respiratory illness (ARill) is common and threatens the health of athletes. ARill in athletes forms a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to non-infective ARill in athletes. The International Olympic Committee (IOC) Medical and Scientific Committee appointed an international consensus group to review ARill in athletes. Key areas of ARill in athletes were originally identified and six subgroups of the IOC Consensus group established to review the following aspects: (1) epidemiology/risk factors for ARill, (2) infective ARill, (3) non-infective ARill, (4) acute asthma/exercise-induced bronchoconstriction and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport (RTS) and (6) acute nasal/laryngeal obstruction presenting as ARill. Following several reviews conducted by subgroups, the sections of the consensus documents were allocated to 'core' members for drafting and internal review. An advanced draft of the consensus document was discussed during a meeting of the main consensus core group, and final edits were completed prior to submission of the manuscript. This document (part 2) of this consensus focuses on respiratory conditions causing non-infective ARill in athletes. These include non-inflammatory obstructive nasal, laryngeal, tracheal or bronchial conditions or non-infective inflammatory conditions of the respiratory epithelium that affect the upper and/or lower airways, frequently as a continuum. The following aspects of more common as well as lesser-known non-infective ARill in athletes are reviewed: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations and risks of illness during exercise, effects of illness on exercise/sports performance and RTS guidelines.

Resuming professional football (soccer) during the COVID-19 pandemic in a country with high infection rates: a prospective cohort study

OBJECTIVES

The risk of viral transmission associated with contact sports such as football (soccer) during the COVID-19 pandemic is unknown. The aim of this study was to describe the infective and immune status of professional football players, team staff and league officials over a truncated football season resumed at the height of the COVID-19 pandemic in a country with high infection rates and to investigate the clinical symptoms related to COVID-19 infection in professional football players.

METHODS

Prospective cohort study of 1337 football players, staff and officials during a truncated football season (9 weeks) with a tailored infection control programme based on preventive measures and regular SARS-CoV-2 PCR swab testing (every 3-5 days) combined with serology testing for immunity (every 4 weeks). Clinical symptoms in positive participants were recorded using a 26-item, Likert-Scale-based scoring system.

RESULTS

During the study period, 85 subjects returned positive (cycle threshold (cT) ≤30) or reactive (30

CONCLUSION

Football played outdoors involving close contact between athletes represents a limited risk for SARS-CoV-2 infection and severe illness when preventive measures are in place.

Collapse

Key Words

• football
• illness
• respiratory
• soccer
• virus

Collapse

MESH Headings

• Adult
• COVID-19/diagnosis
• COVID-19/immunology
• COVID-19/prevention & control
• COVID-19/transmission
• COVID-19 Testing
• Carrier State
• Communicable Disease Control
• Family Health
• Humans
• Pandemics
• Prospective Studies
• Qatar/epidemiology
• SARS-CoV-2/isolation & purification
• Soccer/statistics & numerical data
• Social Interaction

Collapse

Grants Collapse

Health status, heat preparation strategies and medical events among elite cyclists who competed in the heat at the 2016 UCI Road World Cycling Championships in Qatar

Purpose

Assess the health status and heat preparation strategies of athletes competing in a World Cycling Championships held in hot ambient conditions (37°C, 25% relative humidity, wet-bulb-globe-temperature 27°C) and monitor the medical events arising during competition.

Methods

69 cyclists (~9% of the world championships participants) completed a pre-competition questionnaire. Illnesses and injuries encountered by the Athlete Medical Centre (AMC) were extracted from the race reports.

Results

22% of respondents reported illness symptoms in the 10 days preceding the Championships. 57% of respondents had previously experienced heat-related symptoms (cramping most commonly) while 17% had previously been diagnosed with exertional heat illness. 61% of the respondents had undergone some form of heat exposure prior to the Championships, with 38% acclimating for 5 to 30 days. In addition, several respondents declared to live in warm countries and all arrived in Qatar ~5 days prior to their event. 96% of the respondents used a pre-cooling strategy for the time trials and 74% did so before the road race (p<0.001), with ice vests being the most common. The AMC assessed 46 injuries and 26 illnesses in total, with three cyclists diagnosed with heat exhaustion.

Conclusions

The prevalence of previous heat illness in elite cyclists calls for team and event organisation doctors to be trained on heat illness management, including early diagnosis and rapid on-site cooling. Some cyclists had been exposed to the heat prior to the Championships, but few had a dedicated plan, calling for additional education on the importance of heat acclimation. Pre-cooling was widely adopted.

Serum ferritin distribution in elite athletes

OBJECTIVES

It is not uncommon for athletes to be diagnosed with iron deficiency, yet there remains uncertainty whether the prevalence of suboptimal iron status in elite athletes differs from the normal population or warrants routine screening. The purpose of this study is to describe the distribution of serum ferritin (SF) in a cohort of elite athletes.

DESIGN

Retrospective cohort study.

METHODS

Electronic health records of 1085 elite adult athletes (570 women, 515 men) from 2012-2017 were examined retrospectively. SF values were compared to published normal population data. The proportion of athletes meeting criterion values for iron deficiency or initiation of treatment was examined.

RESULTS

SF distributions in male athletes were significantly lower than normal males aged 20 to <24yrs. (χ² 28.8, p<0.001) and aged 24 to <28yrs. (χ² 91.9, p<0.001). SF status was similar in female athletes and normal women aged 20 to <24yrs. (χ² 9.5, p>0.05) or aged 24 to <28yrs. (χ² 11.5, p>0.05). Using 35ng/ml as the criterion value for stage one iron deficiency, 15% of male athletes and 52% of female athletes displayed suboptimal iron status.

CONCLUSIONS

Male athletes have a significantly lower population distribution of SF values as compared to normative data on healthy males, with 15% of male athletes having suboptimal SF status. The distribution of SF values in elite female athletes did not differ from population values, however approximately half women athletes were iron deficient. These data suggest that iron screening should be considered in both male and female athlete populations.

Core temperature up to 41.5ºC during the UCI Road Cycling World Championships in the heat

Objective

To characterise the core temperature response and power output profile of elite male and female cyclists during the 2016 UCI Road World Championships. This may contribute to formulating environmental heat stress policies.

Methods

Core temperature was recorded via an ingestible capsule in 10, 15 and 15 cyclists during the team time trial (TTT), individual time trial (ITT) and road race (RR), respectively. Power output and heart rate were extracted from individual cycling computers. Ambient conditions in direct sunlight were hot (37°C±3°C) but dry (25%±16% relative humidity), corresponding to a wet-bulb globe temperature of 27°C±2°C.

Results

Core temperature increased during all races (p<0.001), reaching higher peak values in TTT (39.8°C±0.9°C) and ITT (39.8°C±0.4°C), relative to RR (39.2°C±0.4°C, p<0.001). The highest temperature recorded was 41.5°C (TTT). Power output was significantly higher during TTT (4.7±0.3 W/kg) and ITT (4.9±0.5 W/kg) than RR (2.7±0.4 W/kg, p<0.001). Heart rate increased during the TTs (p<0.001) while power output decreased (p<0.001).

Conclusion

85% of the cyclists participating in the study (ie, 34 of 40) reached a core temperature of at least 39°C with 25% (ie, 10 of 40) exceeding 40°C. Higher core temperatures were reached during the time trials than the RR.

The need for an alternative method to determine intravascular volumes

It is well described that numerous environmental factors, including exercise, modulate plasma volume (PV). These modulations prove problematic when a number of haematological markers are measured as a concentration in blood plasma. A primary example is haemoglobin concentration ([Hb]), a marker of erythropoiesis commonly used within medicine and also used to detect blood doping. Natural changes in PV can confound [Hb] values when a volume change is detected rather than a true change in haemoglobin mass (Hb_mass) (e.g. volume expansion resulting in a [Hb] decrease and pseudo-anemia vs. Hb_mass decline resulting in anaemia). Currently, there is no simple solution to correct for PV shifts, and this has proven problematic when monitoring volumetric health markers in clinical and anti-doping settings. This narrative review explores the influence that PV shifts have on volumetric biomarkers, such as [Hb]. The progressive expansion in PV observed during multi-day endurance events will be summarised, and the observed impact PV variance has on concentration-based markers will be quantified. From this, the need for alternative methods to correct [Hb] for volume fluctuations is highlighted. Available methods for calculating intravascular volumes are then discussed, with a focus on a recently developed approach using a panel of 'volume descriptive' biomarkers from a standard blood test. Finally, the practical applications of this novel PV blood test within both anti-doping and clinical settings will be examined.

Influence of combined iron supplementation and simulated hypoxia on the haematological module of the athlete biological passport

The integrity of the athlete biological passport (ABP) is underpinned by understanding normal fluctuations of its biomarkers to environmental or medical conditions, for example, altitude training or iron deficiency. The combined impact of altitude and iron supplementation on the ABP was evaluated in endurance-trained athletes (n = 34) undertaking 3 weeks of simulated live-high: train-low (14 h.d^-1 , 3000 m). Athletes received either oral, intravenous (IV) or placebo iron supplementation, commencing 2 weeks prior and continuing throughout hypoxic exposure. Venous blood was sampled twice prior, weekly during, and up to 6 weeks after altitude. Individual ABP thresholds for haemoglobin concentration ([Hb]), reticulocyte percentage (%retic), and OFF score were calculated using the adaptive model and assessed at 99% and 99.9% specificity. Eleven athletes returned values outside of the calculated reference ranges at 99%, with 8 at 99.9%. The percentage of athletes exceeding the thresholds in each group was similar, but IV returned the most individual occurrences. A similar frequency of abnormalities occurred across the 3 biomarkers, with abnormal [Hb] and OFF score values arising mainly during-, and %retic values mainly post- altitude. Removing samples collected during altitude from the model resulted in 10 athletes returning abnormal values at 99% specificity, 2 of whom had not triggered the model previously. In summary, the abnormalities observed in response to iron supplementation and hypoxia were not systematic and mostly in line with expected physiological adaptations. They do not represent a uniform weakness in the ABP. Nevertheless, altitude training and iron supplementation should be carefully considered by experts evaluating abnormal ABP profiles.

The Athlete Biological Passport: How to Personalize Anti-Doping Testing across an Athlete's Career?

For decades, drug testing has been the main instrument at the disposal of anti-doping authorities. The availability in the 1980s of substances identical to those produced by the human body, including the "big 3" (erythropoietin, testosterone, and growth hormone), necessitated a new paradigm in anti-doping. The athlete biological passport (ABP) is a new paradigm, complementary to traditional drug testing, based on the personalized monitoring of doping biomarkers. Athletes who abuse doping substances do so to trigger physiological changes that provide performance enhancement. The ABP aims to detect these changes through its 3 hematological, steroidal, and endocrine modules. Any deviation of a biomarker from what is expected in a healthy physiological condition can be attributable to doping or a medical condition, which, interestingly, is also the criterion used to define a banned substance. Recent advances in proteomics and metabolomics offer immense opportunities to enhance the ABP. The ABP shares multiple aspects with the present customization of health care and personalized medicine.

The use of biomarkers to describe plasma-, red cell-, and blood volume from a simple blood test

Plasma volume and red cell mass are key health markers used to monitor numerous disease states, such as heart failure, kidney disease, or sepsis. Nevertheless, there is currently no practically applicable method to easily measure absolute plasma or red cell volumes in a clinical setting. Here, a novel marker for plasma volume and red cell mass was developed through analysis of the observed variability caused by plasma volume shifts in common biochemical measures, selected based on their propensity to present with low variations over time. Once a month for 6 months, serum and whole blood samples were collected from 33 active males. Concurrently, the CO-rebreathing method was applied to determine target levels of hemoglobin mass (HbM) and blood volumes. The variability of 18 common chemistry markers and 27 Full Blood Count variables was investigated and matched to the observed plasma volume variation. After the removal of between-subject variations using a Bayesian model, multivariate analysis identified two sets of 8 and 15 biomarkers explaining 68% and 69% of plasma volume variance, respectively. The final multiparametric model contains a weighting function to allow for isolated abnormalities in single biomarkers. This proof-of-concept investigation describes a novel approach to estimate absolute vascular volumes, with a simple blood test. Despite the physiological instability of critically ill patients, it is hypothesized the model, with its multiparametric approach and weighting function, maintains the capacity to describe vascular volumes. This model has potential to transform volume management in clinical settings. Am. J. Hematol. 92:62-67, 2017. © 2016 Wiley Periodicals, Inc.

Impact of Altitude on Power Output during Cycling Stage Racing

PURPOSE

The purpose of this study was to quantify the effects of moderate-high altitude on power output, cadence, speed and heart rate during a multi-day cycling tour.

METHODS

Power output, heart rate, speed and cadence were collected from elite male road cyclists during maximal efforts of 5, 15, 30, 60, 240 and 600 s. The efforts were completed in a laboratory power-profile assessment, and spontaneously during a cycling race simulation near sea-level and an international cycling race at moderate-high altitude. Matched data from the laboratory power-profile and the highest maximal mean power output (MMP) and corresponding speed and heart rate recorded during the cycling race simulation and cycling race at moderate-high altitude were compared using paired t-tests. Additionally, all MMP and corresponding speeds and heart rates were binned per 1000 m (<1000 m, 1000-2000, 2000-3000 and >3000 m) according to the average altitude of each ride. Mixed linear modelling was used to compare cycling performance data from each altitude bin.

RESULTS

Power output was similar between the laboratory power-profile and the race simulation, however MMPs for 5-600 s and 15, 60, 240 and 600 s were lower (p ≤ 0.005) during the race at altitude compared with the laboratory power-profile and race simulation, respectively. Furthermore, peak power output and all MMPs were lower (≥ 11.7%, p ≤ 0.001) while racing >3000 m compared with rides completed near sea-level. However, speed associated with MMP 60 and 240 s was greater (p < 0.001) during racing at moderate-high altitude compared with the race simulation near sea-level.

CONCLUSION

A reduction in oxygen availability as altitude increases leads to attenuation of cycling power output during competition. Decrement in cycling power output at altitude does not seem to affect speed which tended to be greater at higher altitudes.

The effect of cumulative endurance exercise on leptin and adiponectin and their role as markers to monitor training load

Leptin and adiponectin play an essential role in energy metabolism. Leptin has also been proposed as a marker for monitoring training load. So far, no studies have investigated the variability of these hormones in athletes and how they are regulated during cumulative exercise. This study monitored leptin and adiponectin in 15 endurance athletes twice daily in the days before, during and after a 9-day simulated cycling stage race. Adiponectin significantly increased during the race (p = 0.001) and recovery periods (p = 0.002) when compared to the baseline, while leptin decreased significantly during the race (p < 0.0001) and returned to baseline levels during the recovery period. Intra-individual variability was substantially lower than inter-individual variability for both hormones (leptin 34.1 vs. 53.5%, adiponectin 19% vs. 37.2%). With regards to exercise, this study demonstrated that with sufficient, sustained energy expenditure, leptin concentrations can decrease within the first 24 hours. Under the investigated conditions there also appears to be an optimal leptin concentration which ensures stable energy homeostasis, as there was no significant decrease over the subsequent race days. In healthy endurance athletes the recovery of leptin takes 48-72 hours and may even show a supercompensation-like effect. For adiponectin, significant increases were observed within 5 days of commencing racing, with these elevated values failing to return to baseline levels after 3 days of recovery. Additionally, when using leptin and adiponectin to monitor training loads, establishing individual threshold values improves their sensitivity.

Iron deficiency in sports - definition, influence on performance and therapy

Iron deficiency is frequent among athletes. All types of iron deficiency may affect physical performance and should be treated. The main mechanisms by which sport leads to iron deficiency are increased iron demand, elevated iron loss and blockage of iron absorption due to hepcidin bursts. As a baseline set of blood tests, haemoglobin, haematocrit, mean cellular volume, mean cellular haemoglobin and serum ferritin levels help monitor iron deficiency. In healthy male and female athletes >15 years, ferritin values <15 mcg are equivalent to empty, values from 15 to 30 mcg/l to low iron stores. Therefore a cut-off of 30 mcg/l is appropriate. For children aged from 6-12 years and younger adolescents from 12-15 years, cut-offs of 15 and 20 mcg/l, respectively, are recommended. As an exception in adult elite sports, a ferritin value of 50 mcg/l should be attained in athletes prior to altitude training, as iron demands in these situations are increased. Treatment of iron deficiency consists of nutritional counselling, oral iron supplementation or, in specific cases, by intravenous injection. Athletes with repeatedly low ferritin values benefit from intermittent oral substitution. It is important to follow up the athletes on an individual basis, repeating the baseline blood tests listed above twice a year. A long-term daily oral iron intake or i.v. supplementation in the presence of normal or even high ferritin values does not make sense and may be harmful.

Within-subject haemoglobin variation in elite athletes: a longitudinal investigation of 13 887 haemoglobin concentration readings

The Athlete Biological Passport (ABP) estimates individualized reference ranges for key blood markers, such as haemoglobin concentration ([Hb]), using predetermined population mean, between- and within-subject variances. Here, we aim to reassess previously published estimates for within-subject [Hb] variance and determine whether sex-, analyzer-, sport-, or season-specific values are required. Our reference population contains 7723 male (mean ± SD, 22.3 ± 4.6 years of age) and 6164 female (21.6 ± 4.3) athlete observations from 49 sports. [Hb] was calculated using one of three cytometers; Bayer-H3 (1997-1999, n = 4554), ADVIA-120 (1999-2010, n = 8636) and Sysmex XT-2000i (2010-2012, n = 697). The final model was a linear mixed model for [Hb] with analyzer (H3, ADVIA, Sysmex), sex (male, female), sport (power-endurance, endurance, skill, team, disabled and non-athletes), season (summer, winter), and the interaction between sex and sport as fixed effects and athlete as a random effect. The model included an exponential correlation structure to allow for within-subject autocorrelation, and allowed different within-subject variances for each sport. Within-subject [Hb] variance (g(2) /L(2) ) was significantly less for power endurance (35.09, 95% CI 33.50 to 36.76), disabled (25.82, 95% CI 21.71 to 35.28) and non-athletes (34.30, 95% CI 28.53 to 35.87) than for endurance (40.35, 95% CI 39.62 to 47.22) and team sports (38.70, 95% CI 37.68 to 39.76) athletes. No new evidence was found to justify adjusting the current within-subject [Hb] variance estimate.

The effect of a period of intensive exercise on the isoform test to detect growth hormone doping in sports

OBJECTIVE

The major objective of this study was to investigate the effects of several days of intense exercise on growth hormone (hGH) testing using the World Anti-Doping Agencies hGH isoform differential immunoassays. Additionally the effects of circadian variation and exercise type on the isoform ratios were also investigated.

STUDY DESIGN

15 male athletes performed a simulated nine day cycling stage race. Blood samples were collected twice daily over a period of 15 days (stage race+three days before and after). hGH isoforms were analysed by the official WADA immunoassays (CMZ Assay GmbH).

RESULTS

All measured isoform ratios were far below the WADA decision limits for an adverse analytical finding. Changes in the isoform ratios could not be clearly connected to circadian variation, exercise duration or intensity.

CONCLUSIONS

The present study demonstrates that the hGH isoform ratios are not significantly affected by exercise or circadian variation. We demonstrated that heavy, long term exercise does not interfere with the decision limits for an adverse analytical finding.

Variability of serum markers of erythropoiesis during 6 days of racing in highly trained cyclists

The athlete biological passport for the fight against doping is currently based on longitudinal monitoring for abnormal changes in cellular blood parameters. Serum parameters related to altered erythropoiesis could be considered for inclusion in the passport. The aim of this study was to quantify the changes in such parameters in athletes during a period of intense exercise.12 highly trained cyclists tapered for 3 days before 6 days of simulated intense stage racing. Morning and afternoon blood samples were taken on most days and analysed for total protein, albumin, soluble transferrin receptor and ferritin concentrations. Plasma volume was determined via total haemoglobin mass measured by carbon-monoxide rebreathing. Percent changes in means from baseline and percent standard errors of measurement (analytical error plus intra-athlete variation) on each measurement occasion were estimated with mixed linear modelling of log-transformed measures. Means of all variables changed substantially in the days following the onset of racing, ranging from -13% (haemoglobin concentration) to +27% (ferritin). After the second day, errors of measurement were generally twice those at baseline. Plasma variables were affected by heavy exercise, either because of changes in plasma volume (total protein, albumin, haemoglobin), acute phase/inflammatory reactions (ferritin) or both (soluble transferrin receptor). These effects need to be taken into consideration when integrating a plasma parameter into the biological passport model for athletes.

Circulating microRNAs as biomarkers for detection of autologous blood transfusion

MicroRNAs (miRNAs) are small non-coding RNAs that regulate various biological processes. Cell-free miRNAs measured in blood plasma have emerged as specific and sensitive markers of physiological processes and disease. In this study, we investigated whether circulating miRNAs can serve as biomarkers for the detection of autologous blood transfusion, a major doping technique that is still undetectable. Plasma miRNA levels were analyzed using high-throughput quantitative real-time PCR. Plasma samples were obtained before and at several time points after autologous blood transfusion (blood bag storage time 42 days) in 10 healthy subjects and 10 controls without transfusion. Other serum markers of erythropoiesis were determined in the same samples. Our results revealed a distinct change in the pattern of circulating miRNAs. Ten miRNAs were upregulated in transfusion samples compared with control samples. Among these, miR-30b, miR-30c, and miR-26b increased significantly and showed a 3.9-, 4.0-, and 3.0-fold change, respectively. The origin of these miRNAs was related to pulmonary and liver tissues. Erythropoietin (EPO) concentration decreased after blood reinfusion. A combination of miRNAs and EPO measurement in a mathematical model enhanced the efficiency of autologous transfusion detection through miRNA analysis. Therefore, our results lay the foundation for the development of miRNAs as novel blood-based biomarkers to detect autologous transfusion.

Flow cytometric assessment of erythrocyte shape through analysis of FSC histograms: use of kurtosis and implications for longitudinal evaluation

Sphericity of erythrocytes can be estimated from analysis of FSC signal distribution in flow cytometry. Previously, Pearson's coefficient of dissymmetry (PCD) and spherical index (SphI) were applied to determine erythrocyte sphericity from the FSC histogram. The aim of the present study is to illustrate the application of kurtosis as an indicator of erythrocyte sphericity in flow cytometry in a broad range of FSC distributions. Moreover, the possibility of longitudinal evaluation of erythrocyte sphericity is studied. Change of erythrocyte sphericity of 10 healthy subjects was induced by variation of buffer osmolarity to validate applicability of sphericity measures. Agreement between the sphericity indicators was then studied in samples from 20 healthy donors taken at three time points, which were processed through density gradient centrifugation and incubated with FITC-labelled antibodies to induce a broad variation of erythrocyte form (1086 samples). SphI, PCD and kurtosis of FSC distribution were calculated. Correlation of the respective measures, standard error of measurement (SEM) and r ratio (intra- to interindividual variance) were determined to illustrate agreement between the sphericity indicators. In the first study part, all sphericity indicators illustrated change of erythrocyte shape as induced by osmolarity variation. In the second part, correlation between kurtosis and SphI was -0.97 and correlation between kurtosis and PCD was 0.58 (p<0.05). In isotype control samples, correlation between kurtosis and SphI was -0.98 and correlation between kurtosis and PCD was 0.48 (p<0.05). In these samples, mean kurtosis was -0.80 (SEM 0.03), mean SphI was 2.19 (SEM 0.04) and mean PCD was -0.31 (SEM 0.02). r ratios of all measures of sphericity were <0.6. Our results show that kurtosis is closely correlated with SphI in a broad range of erythrocyte FSC distributions. Moreover, all measures of sphericity feature r ratios <0.6, highlighting that erythrocyte sphericity appears as a feasible parameter for individual longitudinal data monitoring.

Longitudinal observation of Epstein-Barr virus antibodies in athletes during a competitive season

Epstein-Barr virus (EBV) serology continues to be the first diagnostic test when infectious mononucleosis is suspected. Due to possible mild immunosuppression in competitive athletes, EBV reactivation determined by increases in salivary viral load have been identified as one possible cause in recurrent respiratory infections. The long-term variation in EBV antibody levels in athletes compared to a control group remains unclear. The purpose of the study was to investigate the time course of changes in concentration of EBV antibodies in athletes with special emphasis on antibodies against early antigens (EAs) and avidity determination. During a competition season of approximately 12 months, the serological status of 15 biathletes (age 27 ± 3 years, 7 female, 8 male, international to Olympic level) was compared with 11 controls (age 23 ± 1 years; 1 female 10 male) at multiple time points. In addition, 43 healthy swimmers (age 22 ± 4 years, 18 female, 25 male, national to international level) were tested to validate the results with only two time points interspersed by approximately 6 months of intensive physical exercise. Analysis of quantitative antibody intensity bands revealed stable values during a competition season. In particular, IgG-antibodies against EAs may persist and were found in 15% of past infections in swimmers exhibiting fluctuations in concentration after 6 months. These results provide evidence that positive Anti-EA-IgG may persist in healthy athletes and thus, should not be used to diagnose EBV reactivations or to identify a compromised immune function.

Scientific Expertise and the Athlete Biological Passport: 3 Years of Experience

Expert evaluation of biological data is a key component of the Athlete Biological Passport approach in the fight against doping. The evaluation consists of a longitudinal assessment of biological variables to determine the probability of the data being physiological on the basis of the athlete's on own previous values (performed by an automated software system using a Bayesian model) and a subjective evaluation of the results in view of possible causes (performed by experts). The role of the expert is therefore a key component in the process. Experts should be qualified to evaluate the data regarding possible explanations related to the influence of doping products and methods, analytical issues, and the influence of exercise or pathological conditions. The evaluation provides a scientific basis for the decision taken by a disciplinary panel. This evaluation should therefore encompass and balance all possible causes for a given blood profile and provide a likelihood for potential scenarios (pathology, normal variation, doping) that might have caused the pattern. It should comply with the standards for the evaluation of scientific evidence in forensics.

On the basis of their evaluation of profiles, experts might provide assistance in planning appropriate target testing schemes.

Detection of EPO doping and blood doping: the haematological module of the Athlete Biological Passport

The increase of the body's capacity to transport oxygen is a prime target for doping athletes in all endurance sports. For this pupose, blood transfusions or erythropoiesis stimulating agents (ESA), such as erythropoietin, NESP, and CERA are used. As direct detection of such manipulations is difficult, biomarkers that are connected to the haematopoietic system (haemoglobin concentration, reticulocytes) are monitored over time (Athlete Biological Passport (ABP)) and analyzed using mathematical models to identify patterns suspicious of doping. With this information, athletes can either be sanctioned directly based on their profile or targeted with conventional doping tests. Key issues for the appropriate use of the ABP are correct targeting and use of all available information (e.g. whereabouts, cross sectional population data) in a forensic manner. Future developments of the passport include the correction of all concentration-based variables for shifts in plasma volume, which might considerably increase sensitivity. New passport markers from the genomic, proteomic, and metabolomic level might add further information, but need to be validated before integration into the passport procedure. A first assessment of blood data of federations that have implemented the passport show encouraging signs of a decreased blood-doping prevalence in their athletes, which adds scientific credibility to this innovative concept in the fight against ESA- and blood doping.

Changes in blood lactate concentrations during different treadmill exercise test protocols

AIM

The purpose of this study was to compare the blood-lactate and heart rate response of three treadmill tests and to define a conversion algorithm.

METHODS

Subjects included 19 long-distance runners. The first two tests had increments of 2 km/h every 3 (test3m) or 5 minutes (test5m). The third test (testFm) consisted of four consecutive 2000m-runs. The calculated individual-anaerobic-threshold (IAT) from test3m was defined as speed at the third step of testFm, speed-increments between the four steps were 0.25 m/s.

RESULTS

Lactate threshold (LT) did not show significant differences. Speed at IAT in test3m (15.09|*plusmn*|2.29 km/h) was significantly higher than in test5m (14.74|*plusmn*|2.22 km/h), heart rates were nearly identical. Speed and heart rate at 2 mmol/L showed no significant differences. At lactate concentrations of 3 and 4 mmol/L, running-speeds in test3m were significantly higher than in test5m and testFm. Heart rate were the same in test3m and test5m but significantly higher in testFm.

CONCLUSION

Taking test3m as basis for determining endurance-performance, an adjustment of test5m can be made by adding 1.8 mmol/l instead of 1.5 mmol/l to the LT to derive the IAT. TestFm shows similar results as test5m, however, standardization is difficult due to variable increment durations.

Detection of autologous blood doping with adaptively evaluated biomarkers of doping: a longitudinal blinded study

BACKGROUND

Since no direct detection method for autologous blood transfusions exists, the most promising attempt is the Athlete Biological Passport (ABP) and its adaptive model that enables a longitudinal monitoring of hematologic measures to identify patterns of blood manipulations. The purpose therefore was to evaluate the performance of this adaptive model for the detection of autologous blood transfusions in a longitudinal blinded setting.

STUDY DESIGN AND METHODS

Twenty-one subjects were divided into a doped group (multiple transfusions of 1-2 units of red blood cells, n = 11) and a control group (n = 10). The time course of a cycling season (42 weeks) was simulated including three major competitions (Classics, Grand Tour, World Championships). Up to 10 venous blood samples were ordered per subject by a blinded investigator mimicking the intelligent approach in obtaining hematologic data for the adaptive model (hemoglobin [Hb] concentration, reticulocyte percentage, OFF-score).

RESULTS

Retrospective analysis allowed identification of four (probability >99%) or three (probability >99.9%) abnormal samples for Hb and eight (probability >99%) or five (probability >99.9%) abnormal samples for OFF-hr in doped subjects. Four doped subjects (36%) presented an abnormal OFF-hr sequence and three doped subjects (27%) an abnormal Hb sequence; there were no false-positive sequence results. The best possible sensitivity was 82% when a combination of all tests was used.

CONCLUSIONS

This investigation provides evidence that the adaptive model allows detection of autologous blood transfusions with a good sensitivity. An intelligent testing approach and the adherence to World Anti-Doping Agency's ABP operating guidelines are nevertheless determinant in the success.

The impact of acute gastroenteritis on haematological markers used for the athletes biological passport - report of 5 cases

The haematological module of the "Athletes Biological Passport" (ABP) is used to detect blood doping through the longitudinal variation of blood variables, such as haemoglobin concentration (Hb). Sporting federations have opened disciplinary procedures against athletes based on ABP results. Suspicious athletes try to explain the variations in their blood values with dehydration caused by gastrointestinal (GI) problems. The aim of the present report is to describe haemoglobin concentration, a key variable of the ABP, during acute gastroenteritis in athletes. 5 athletes with severe gastroenteritis were studied in retrospective. Blood test results (Hb, white blood cell count (WBC) and differential, CRP) obtained on hospital admission for GI problems were compared to data obtained from the same athletes in states of good health on previous occasions. During GI problems, athletes displayed marked inflammatory constellations with increased CRP and typical WBC shifts. Hb was not affected and remained mostly unchanged. This is in line with basic physiologic fluid regulation, where plasma volume is kept constant, even under conditions of severe dehydration. It is therefore unlikely that fluid loss associated with gastroenteritis will cause athletes blood data to reach levels of abnormality that will be suspicious of blood doping.

Relations between haemoglobin mass, cardiac dimensions and aerobic capacity in endurance trained cyclists

AIM

Chronic endurance exercise triggers increased cardiac dimensions, blood volumes and haemoglobin mass (Hb mass). Cardiac output and Hb mass are considered as independent contributors to aerobic performance. Therefore, increased Hb mass could counterbalance for a relative deficiency in cardiac adaptation. The purpose of the present study is to investigate relations between Hb mass and cardiac dimensions in a group of endurance athletes with respect to aerobic capacity.

METHODS

Two groups of highly trained cyclists featuring high (HHB group, N.=13) and low (LHB group, N.=13) Hb mass (measured by a CO-rebreathing method) were compared for measures of aerobic performance, cardiac wall thickness, cavity size and left ventricular mass (determined by 2-D-echocardiography). Lean body mass (LBM) was chosen as anthropometrical reference for Hb mass.

RESULTS

HHB featured higher cardiac wall thickness than LHB, but no difference appeared in cardiac cavity size, left ventricular mass and the performance parameters. Normalising Hb mass for body weight instead of LBM improved correlations between Hb mass and performance parameters.

CONCLUSIONS

Our data provides new evidence for a connection between cardiac wall thickness and Hb mass in endurance athletes but no further evidence for a counterbalance between Hb mass and cardiac adaptation was found. Moreover, we postulate that Hb mass loses predictive value for aerobic performance when normalised for LBM.

Total haemoglobin mass but not cardiac volume adapts to long-term endurance exercise in highly trained spinal cord injured athletes

The oxygen transport system is an important component in the limitation of endurance performance in able-bodied and paraplegic athletes. The aim of the present study was to investigate the total haemoglobin mass (tHb, carbon monoxide rebreathing method) and cardiac volume (HV, echocardiography) in 25 highly endurance trained male spinal cord injured (mainly paraplegic) athletes (SCI-TRAINED) and to compare the results with those of 10 untrained spinal cord injured controls (SCI-UNTRAINED) and in 25 able-bodied elite endurance athletes (TRAINED). tHb and tHb/kg were higher in SCI-TRAINED than in SCI-UNTRAINED (748 +/- 110 vs. 629 +/- 209 g (464 +/- 68 vs. 390 +/- 130 mmol) (mean +/- SD), P = 0.02 and 10.3 +/- 1.3 vs. 7.9 +/- 2.0 g/kg (6.4 +/- 0.8 vs. 4.9 +/- 1.2 mmol/kg), P < 0.0001), while HV and HV/kg showed no significant differences between the two groups (765 +/- 93 vs. 793 +/- 164 ml and 10.6 +/- 1.4 vs. 10.3 +/- 2.5 ml/kg). No difference between SCI-TRAINED and TRAINED was found for septal diameter (9.5 +/- 1.0 mm vs. 9.7 +/- 0.7 mm). However, tHb and tHb/kg in SCI-TRAINED was lower than in TRAINED [896 +/- 123 g (556 +/- 76 mmol), P = 0.0003 and 12.6 +/- 1.3 g/kg (7.8 +/- 0.8 mmol), P < 0.0001]. In spinal cord injured athletes, tHb but not HV adapts moderately to chronic endurance exercise, although tHb in spinal cord injured athletes does not reach the level of able-bodied-trained persons.

Evaluation of anthropometrical reference parameters for hemoglobin mass in endurance athletes

AIM

Blood volume and hemoglobin mass (tHb) are new emerging parameters in exercise physiology. The appropriate anthropometrical reference for these variables has not yet been investigated. In most current investigations, body weight is used in this context. The aim of the present study was therefore to evaluate three different anthropometrical parameters (body weight, body surface area [BSA] and lean body mass [LBM] with respect to tHb.

METHODS

Sixty-five healthy male endurance athletes underwent a tHb determination (optimised CO rebreathing method) and anthropometrical evaluation (skinfold measurement) with estimation of body weight, LBM and BSA. Correlation analysis was performed; the correlations of the different anthropometrical reference ratios were compared and evaluated with regards to body composition.

RESULTS

LBM showed the best correlation with tHb (R=0.81), although no significant differences between the three anthropometrical references were found (BSA R=0.76, body weight R=0.77). In contrast to tHb/body weight, tHb/LBM was independent of body fat content and thus body composition.

CONCLUSION

The current study demonstrated no statistical difference between various anthropometrical references for tHb, which might be due to the anthropometrically homogenous study group of lean, endurance trained athletes. However, the significance dependence of body weight on body fat content indicates that this might not be the case in athletes of other somatotypes. It is therefore suggested that LBM instead of body weight should be used as anthropometrical reference when investigating tHb in athletes.

Haemoglobin Mass in Cyclists during Stage Racing

Haemoglobin mass is a main determinant of maximal oxygen uptake. Blood doping aims at increasing this variable. Limits for haematocrit and haemoglobin concentration are used as indicators of blood doping. However, these variables are measures of concentration, do not represent total haemoglobin mass and are altered by vascular volumes shifts. Direct estimation of haemoglobin mass could improve blood tests. It is unknown if physical exercise alters haemoglobin mass. The purpose of this study was to investigate the reaction of haemoglobin mass and other vascular compartments to heavy exercise in athletes. Haemoglobin mass and vascular compartments were evaluated using the optimised CO rebreathing method in 7 elite cyclists during a stage race. Simultaneously, haemoglobin concentration and haematocrit were analysed. Haemoglobin mass (pre-race 958 +/- 123 g, end race 948 +/- 106 g) and red cell volume did not change significantly over the study period, while plasma volume and blood volume tended to increase. Haematocrit (pre-race 44.1 +/- 2.5 %, end race 40.9 +/- 1.59 %) and haemoglobin concentration (pre race 15.8 +/- 0.9 g/dl, end race 14.7 +/- 0.7 g/dl) decreased. During the study, a plasma volume expansion as adaptation to prolonged exercise occurred. Haemoglobin concentration and haematocrit decreased accordingly, whereas haemoglobin mass remained stable. Haemoglobin mass might therefore be a suitable screening tool for blood manipulations.

Hb Mass Measurement Suitable to Screen for Illicit Autologous Blood Transfusions

PURPOSE

An increase of hemoglobin (Hb) mass is the key target of blood doping practices to enhance performance as it is a main determinant of maximal oxygen uptake. Although detection methods exist for doping with recombinant EPO and homologous blood transfusions, autologous transfusions remain virtually undetectable. In this context, the most sensitive parameter would be a determination of Hb mass itself. The purpose therefore was to establish whether Hb mass measurements by the optimized CO-rebreathing method allow screening for the withdrawal and reinfusion of autologous red blood cells.

METHODS

The optimized CO-rebreathing method was used for evaluation of Hb mass in two groups at three time points (duplicate measurements: 1) baseline, 2) after donation, and 3) after reinfusion). Group I (N = 6) was to donate and receive 1 unit of packed red cells (PRC) in contrast to two PRC in group II (N = 4). The time span between withdrawal and reinfusion was 2 d.

RESULTS

The mean Hb content of the blood units was 59.0 +/- 3.9 g (group I) and 108.3 +/- 1.3 g (group II). Hb mass decreased significantly after blood withdrawal (-89 +/- 16 g in group I and -120 +/- 14 g in group II) and increased significantly after reinfusion (group I: 70 +/- 16 g; group II: 90 +/- 9 g) but was lower than at baseline (group I: -19 +/- 17 g; group II: -30 +/- 14 g). The total error of measurements for the duplicate measures ranged between 0.8 and 3.1% (Hb mass: 6.4-22.1 g).

CONCLUSION

Hb mass determination with the optimized CO-rebreathing method has sufficient precision to detect the absolute differences in Hb mass induced by blood withdrawal and autologous reinfusion. Thus, it may be suited to screen for artificially induced alterations in Hb mass.

Cycling power output produced during flat and mountain stages in the Giro d'Italia: A case study

Until recently, the physiological demands of cycling competitions were mostly reflected by the measurement of heart rate and the indirect estimation of exercise intensity. The purpose of this case study was to illustrate the varying power output of a professional cyclist during flat and mountain stages of a Grand Tour (Giro d'Italia). Nine stage recordings of a cyclist of the 2005 Giro d'Italia were monitored using a mobile power measurement device (SRM Trainingssystem, Julich, Germany), which recorded direct power output and heart rate. Stages were categorized into flat (n = 5) and mountain stages (n = 4). Data were processed electronically, and the overall mean power in flat and mountain stages and maximal mean power for various durations were calculated. Mean power output was 132 W +/- 26 (2.0 W x kg(-1) +/- 0.4) for the flat and 235 W +/- 10 (3.5 W x kg(-1) +/- 0.1) for the mountain stages. Mountain stages showed higher maximal mean power (367 W) for longer durations (1800 s) than flat stages (239 W). Flat stages are characterized by a large variability of power output with short bursts of high power and long periods with reduced intensity of exercise, whereas mountain stages mostly require submaximal, constant power output over longer periods.

Cadence-power-relationship during decisive mountain ascents at the Tour de France

The aim of the study was to report the relationship between cadence and power developed by professional cyclists during high mountain ascents of the Tour de France. From the 10 cyclists (30 +/- 4 years, 178 +/- 8 cm, 69 +/- 6 kg) involved in the study, 108 ascents were recorded and analyzed using a mobile power measurement device (SRM Training Systems, Jülich, Germany). Based on topographic characteristics, the ascents were categorized into 1st and Hors Category (HC) climbs. During the ascents of the 1st Category climbs, power output averaged 312 +/- 43 W (4.5 +/- 0.6 W/kg) with a mean cadence of 73 +/- 6 rpm and a mean duration of 37 : 41 +/- 16 : 16 min. Power output averaged 294 +/- 36 W (4.3 +/- 0.6 W/kg) at a mean cadence of 70 +/- 6 rpm during 57 : 40 +/- 10 : 32 min on HC climbs. The maximal mean power for long durations (1800 s) showed a mean power output of 327 W and 346 W for the 1st and HC climbs, respectively. The evaluation of the cadence-power output and the distance per pedaling cycle-power output relationship shows that high power outputs are mainly yielded by higher pedaling cadences and higher gears.

Power Output during the Tour de France

The aim of this study was to evaluate the demands of riding a "Grand Tour" by monitoring both heart rate and power output in 15 professional cyclists. SRM power output profiles (SRM Trainingsystem, Jülich, Germany) were collected during 148 mass start stages during the 2005 Tour de France and analyzed to establish average power, heart rate (HR) and cadence produced in different terrain categories (flat [FLT]; semi-mountainous [SMT]; mountainous [MT]). The maximal mean power (MMP) for progressively longer durations was quantified. Average HR was similar between FLT (133 +/- 10 bpm) and SMT (134 +/- 8 bpm) but higher during MT (140 +/- 3 bpm). Average power output revealed a similar trend (FLT 218 +/- 21 W [3.1 +/- 0.3 W/kg], SMT 228 +/- 22 W [3.3 +/- 0.3 W/kg], and MT 234 +/- 13 W [3.3 +/- 0.2 W/kg]). Cadence during MT was approximately 6 - 7 rpm lower (81 +/- 15 rpm) compared to FLT or SMT. During MT stages, the MMP for 1800 sec. was highest (394 W vs. 342 W) but the MMP 15 was lower (836 W vs. 895 W) compared to FLT. The data document comprehensively the power output demands during the Tour de France.

External iliac artery occlusion in a young female cyclist

After 8 years of high performance training in mountain biking, a top female athlete, aged 23, first complained of diffuse, exercise-induced pain in both thighs. Over a period of the next 4 years, a slight but continuous reduction in her performance was observed, despite having maintained her training regime during the first 2 years. Gradually, pain increased, at last occurring even when she climbed a few stairs. This led to a clinical, echo-Doppler, MR-angiographic and DS-angiographic examination, which showed a complete occlusion of the right iliac external artery with good collateralisation. The left external iliac artery evidenced only small intravascular lesions. Surgical treatment (endarterectomy plus patch angioplasty) eliminated the pain completely. Except for a lipoprotein (a) of 114 mg/dL, no other significant risk factors were found. The influence of a genetic (heterocygotic) low APC-ratio of 1.6 and free protein S of 53% is unclear. This is a typical case of a delayed diagnosis in an athlete. A complete occlusion of an external iliac artery is extremely seldom in young in female athletes. With no indication of a general atherosclerotic or inflammatory process nor congenital abnormalities, an exercise-induced, chronic traumatisation may have caused this pathological condition.

Success in elite cycling: A prospective and retrospective analysis of race results

The development of peak performances is a main research focus in sports science. It is unclear how many former top junior athletes achieve success in the elite class later. The aim of the present study was to examine the careers of athletes who participated in major junior or adult/elite cycling events using prospective and retrospective analysis of competition results. The official results of major junior (age < or = 18 years) and elite (age > 18 years) cycling races from 1980 to 2004 were analysed. Age-related aspects, career lengths, and success were compared between riders who presented results in both junior and elite races (JUNIOR ELITE) and riders who had no junior race results (ELITE ONLY). Altogether, 27,454 results of 8004 athletes from 108 countries were collected. We found that 29.4% of the elite athletes had participated in junior World Championships, and that 34% of the participants in junior World Championships later participated in major elite competitions. JUNIOR ELITE athletes are significantly more successful in several cycling disciplines and have their first and last elite result at a younger age than ELITE ONLY athletes. No difference was found in career lengths. The data presented here emphasize the importance of long-term training programmes in the development of peak performance in cycling.

Effects of Hemopure on maximal oxygen uptake and endurance performance in healthy humans

Haemoglobin-based oxygen carriers (HBOCs) such as Hemopure are touted as a tenable substitute for red blood cells and therefore potential doping agents, although the mechanisms of oxygen transport of HBOCs are incompletely understood. We investigated whether infusion of Hemopure increased maximal oxygen uptake (V.O 2max) and endurance performance in healthy subjects. Twelve male subjects performed two 4-minute submaximal exercise bouts equivalent to 60 % and 75 % of V.O (2max) on a cycle ergometer, followed by a ramped incremental protocol to elicit V.O (2max). A crossover design tested the effect of infusing either 30 g (6 subjects) or 45 g (6 subjects) of Hemopure versus a placebo. Under our study conditions, Hemopure did not increase V.O (2max) nor endurance performance. However, the infusion of Hemopure caused a decrease in heart rate of approximately 10 bpm (p=0.009) and an average increase in mean ( approximately 7 mmHg) and diastolic blood pressure ( approximately 8 mmHg) (p=0.046) at submaximal and maximal exercise intensities. Infusion of Hemopure did not bestow the same physiological advantages generally associated with infusion of red blood cells. It is conceivable that under exercise conditions, the hypertensive effects of Hemopure counter the performance-enhancing effect of improved blood oxygen carrying capacity.