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Nº de Abstracts = 30
Modificado em 08 Dezembro de 2010
Blood testing in sport: hematological profilingKuipers H, Dubravcic-Simunjak S, Moran J, Mitchell D, Shobe J, Sakai H, Ambartsumov R.: International Journal of Sports Medicine, 2010, 31(8):542-7 Language: eng Country: Germany University Maastricht, Human Movement Sciences, Maastricht, The Netherlands. Harm. Hemoglobin concentration and percent reticulocytes (%retics) were analyzed in blood samples taken pre-competition, post-competition, and during out of competition testing in elite speed skaters. Percent reticulocytes during screening was not different from the values obtained post-race, and no significant gender difference was found. Mean hemoglobin concentration both in males and females was slightly higher at 1 425 m altitude compared to <750 m altitude (0.23 g/dl increase in males and 0.48 g/dl increase in females; p<0.05 and p<0.01, respectively). Mean %retics at 1 425 m altitude is higher (0.24% in males and 0.27% in females, respectively, p<0.01) compared to blood sampled 2.4% in 52 skaters at least two consecutive samples yielded a percent reticulocytes above 2.4%. In 50 individuals with generally normal values but at least in two consecutive samples values above 2.4% the pattern required additional testing. In conclusion, percent reticulocytes are a robust hematological parameter, including acute exercise.
Clean Olympians? Doping and anti-doping: the views of talented young British athletes., The International Journal on Drug Policy, 2010, 21(4):276-82. Department of Philosophy, History and Law, School of Health Science, Swansea University, Singleton Park, Swansea, United Kingdom. BACKGROUND: Review articles suggest a small but significant proportion (between 3 and 12%) of male adolescents have used anabolic-androgenic steroids (AAS) at some point (Yesalis and Bahrke, 2000; Calfee and Fadale, 2006). In sport, the use of prohibited substances or processes to enhance performance, collectively referred to as 'doping', is banned by both sports' National and International Governing Bodies, and by the World Anti-Doping Agency (WADA) who run an extensive testing programme and educational initiatives designed to foster anti-doping attitudes. METHOD: A total of 40 talented male and female athletes (mean average age 19.6 years) from 13 different sports attended 12 focus groups held over the UK intended to investigate athletes' attitudes toward doping. Focus group transcriptions were analysed and coded with the use of QSR NVivo 8. RESULTS: Athletes in general did not report a significant national doping problem in their sport, but exhibited sporting xenophobia with regard to both doping practices and the stringency of testing procedures outside of the UK. Athletes often viewed doping as 'unnatural' and considered the shame associated with doping to be a significant deterrent. Athletes perceived no external pressure to use performance enhancing drugs. In response to hypothetical questions, however, various factors were acknowledged as potential 'pressure' points: most notably injury recovery and the economic pressures of elite sport. Finally, a significant minority of athletes entertained the possibility of taking a banned hypothetical performance enhancing drug under conditions of guaranteed success and undetectability. CONCLUSIONS: The athletes in this study generally embraced those values promoted in anti-doping educational programmes, although there were some notable exceptions. That the social emotion of shame was considered a significant deterrent suggests anti-doping efforts that cultivate a shared sense of responsibility to remain 'clean' and emphasise the social sanctions associated with being deemed a 'drugs cheat', resonate with this atypical social group.
Drug testing in sport: the attitudes and experiences of elite athletes.Dunn M, Thomas JO, Swift W, Burns L, Mattick RP.: The International Journal on Drug Policy, 2010, 21(4):330-2. National Drug and Alcohol Research Centre, University of New South Wales, Sydney, New South Wales, Australia. BACKGROUND: This study aimed to investigate, among a sample of elite Australian athletes, the extent to which this group supports drug testing as a deterrent to drug use. METHOD: Data was collected from a convenience sample of (n=974) elite Australian athletes who self-completed a questionnaire, and semi-structured telephone surveys with key experts. RESULTS: The athletes surveyed endorsed testing for banned substances as an effective way of deterring drug use; believed that the current punishments for being caught using a banned substance was of the appropriate severity; and indicated that there should be separate policies regarding illicit drug (ID) and performance-enhancing drug (PED) use. CONCLUSION: A large proportion of elite athletes in Australia endorse drug testing as an effective means of deterring drug use. They perceive a difference between being detected using a PED and an ID and believe that penalties should reflect this difference. Future research may wish to investigate attitudes towards newer methods employed to detection drug use.
The effect of sodium bicarbonate ingestion on high-intensity intermittent running and subsequent performancePrice MJ, Simons C.: Journal of strength and conditioning research / National Strength & Conditioning Association, 2010, 24(7):1834-42. Department of Physiology and Sports Science, Faculty of Health and Life Sciences, Coventry University, Coventry, United Kingdom. The purpose of this study was to determine the effects of sodium bicarbonate (NaHCO3) ingestion on intermittent running and subsequent performance. Eight healthy men volunteered to take part in the study. One hour after the ingestion of either NaHCO(3) or placebo (sodium chloride; NaCl) participants undertook 20 x 24-second runs on a motorized treadmill at the velocity eliciting maximal oxygen uptake (100% v-VO(2)max). After sprint 20 participants performed a run to volitional exhaustion at 120% v-VO(2)max. Capillary blood samples for blood pH, bicarbonate ([HCO(3)]), and lactate ([Bla]) concentration were taken pre and postingestion, every fifth sprint and after the performance run. After ingestion of NaHCO(3), blood [HCO(3)] increased from resting values (p < 0.05), and the increase in pH approached significance. Blood [HCO(3)(-)] continually decreased throughout intermittent exercise (p < 0.05) and decreased further after performance in both trials (p < 0.05). [Bla] was similar in both trials throughout intermittent exercise but was greater at exhaustion for NaHCO(3) (main effect for trial; p < 0.05). There was no significant difference in performance of the group between trials (78 +/- 22 and 75 +/- 22 seconds for NaHCO(3) and NaCl, respectively). The intercept of the relationships between [Bla] and [HCO(3)(-)] and between [Bla] and pH was greater during NaHCO(3) (p 0.05). The results of this study suggest that the ingestion of NaHCO(3) before intermittent type exercise was sufficient to induce metabolic alkalosis but did not significantly affect performance. However, because significant individual variations in performance were observed, an individual approach to bicarbonate ingestion is recommended based on the intensity and duration of the required performance.
Hemopoietic and angiogenetic progenitors in healthy athletes: different responses to endurance and maximal exercise.Bonsignore MR, Morici G, Riccioni R, Huertas A, Petrucci E, Veca M, Mariani G, Bonanno A, Chimenti L, Gioia M, Palange P, Testa U.: Journal of Applied Physiology (Bethesda, Md. : 1985), 2010-07 109(1):60-7. Biomedical Department, Internal and Specialistic Medicine (DIBIMIS), Section of Pneumology, University of Palermo, Via Trabucco, 180, 90146 Palermo, Italy. The effects of endurance or maximal exercise on mobilization of bone marrow-derived hemopoietic and angiogenetic progenitors in healthy subjects are poorly defined. In 10 healthy amateur runners, we collected venous blood before, at the end of, and the day after a marathon race (n = 9), and before and at the end of a 1.5-km field test (n = 8), and measured hemopoietic and angiogenetic progenitors by flow cytometry and culture assays, as well as plasma or serum concentrations of several cytokines/growth factors. After the marathon, CD34(+) cells were unchanged, whereas clonogenetic assays showed decreased number of colonies for both erythropoietic (BFU-E) and granulocyte-monocyte (CFU-GM) series, returning to baseline the morning post-race. Conversely, CD34(+) cells, BFU-E, and CFU-GM increased after the field test. Angiogenetic progenitors, assessed as CD34(+)KDR(+) and CD133(+)VE-cadherin(+) cells or as adherent cells in culture expressing endothelial markers, increased after both endurance and maximal exercise but showed a different pattern between protocols. Interleukin-6 increased more after the marathon than after the field test, whereas hepatocyte growth factor and stem cell factor increased similarly in both protocols. Plasma levels of angiopoietin (Ang) 1 and 2 increased after both types of exercise, whereas the Ang-1-to-Ang-2 ratio or vascular endothelial growth factor-A were little affected. These data suggest that circulating hemopoietic progenitors may be utilized in peripheral tissues during prolonged endurance exercise. Endothelial progenitor mobilization after exercise in healthy trained subjects appears modulated by the type of exercise. Exercise-induced increase in growth factors suggests a physiological trophic effect of exercise on the bone marrow.
Anabolic androgenic steroids in amateur sports in the NetherlandsWoerdeman J, de Hon O, Levi M, de Ronde WP.: Nederlands tijdschrift voor geneeskunde, 2010 154(37):A2004. VU Medisch Centrum, Amsterdam, afd. Endocrinologie, the Netherlands. In the Netherlands an estimated 20,000 people use anabolic androgenic steroids (AAS). The use of AAS is particularly common in regular visitors to gyms and fitness centres. AAS are usually synthetic derivatives of testosterone with both an anabolic and an androgenic effect. AAS have many side effects like liver damage (oral use) or infections (intramuscular use), which can be explained partly by the androgenic effect and partly by the manner of use. Many of these side effects are only reported in case studies and have not been systematically investigated.
Effects of induced alkalosis on simulated match performance in elite female water polo players.Tan F, Polglaze T, Cox G, Dawson B, Mujika I, Clark S.: International Journal of Sport Nutrition and Exercise Metabolism, 2010, 20(3):198-205. Sports Science Dept., Singapore Sports Council, Singapore. This study investigated the effects of sodium bicarbonate (NaHCO3) ingestion on simulated water polo match performance. Twelve elite players from the Australian National Women's Water Polo Squad (age 23.7 +/- 3.0 yr, height 1.73 +/- 0.05 m, body mass 75.7 +/- 8.0 kg) participated in the study. In a randomized cross-over double-blind design, players ingested 0.3 g/kg of NaHCO3 or placebo 90 min before performing a 59-min match-simulation test (MST) that included 56 x 10-m maximal-sprint swims as the performance measure. Capillary blood samples were obtained preingestion, pre- and post-warm-up, and after each quarter of the MST. Preexercise ingestion of NaHCO3 was effective in enhancing extracellular pH from baseline levels of 7.41; +/- 0.01 (M; +/- 90% confidence limits) to 7.49; +/- 0.01 and bicarbonate levels from 24.4; +/- 0.3 to 28.5; +/- 0.5 mmol/L. The percentage difference in mean sprint times between trials showed no substantial effects of NaHCO3 (0.4; +/- 1.0, effect size = 0.09; +/- 0.23; p = .51). These findings are contrary to those of previous NaHCO3 studies on simulated team-sport performance, but this investigation is unique in that it examined highly trained athletes performing sport-specific tasks. In conclusion, water polo players should not expect substantial enhancement in intermittent-sprint performance from NaHCO3 supplementation.
Diurnal and exercise-related variability of haemoglobin and reticulocytes in athletes.Schumacher YO, Wenning M, Robinson N, Sottas PE, Ruecker G, Pottgiesser T.: International Journal of Sports Medicine, 2010, 31(4):225-30. Abteilung Sportmedizin, Medizinische Universitätsklinik Freiburg, Germany. Haemoglobin (Hb) and Reticulocytes (Ret) are measured as indirect markers of doping in athletes. We studied the diurnal variation, the impact of exercise, fluid intake and ambient temperature in athletes on these parameters. Hourly venous blood samples were obtained from 36 male athletes of different disciplines (endurance (END) and non-endurance (NON-END)) over 12 h during a typical training day. Seven inactive subjects served as controls (CON). Hb and Ret were determined. A mixed model procedure was used to analyse the data. At baseline, Hb was similar for all groups, END showed lower Ret than NON-END and CON. Exercise showed a significant impact on Hb (+0.46 g/dl, p<0.001), the effect disappeared approximately 2 h after exercise. Hb decreased over the day by approximately 0.55 g/dl (p<0.01). There was no relevant effect on Ret. Fluid intake and ambient temperature had no significant effect. Hb shows significant diurnal- and exercise related variations. In an anti-doping context, most of these variations are in favour of the athlete. Blood samples taken after exercise might therefore provide reliable Results and thus be used for the longitudinal monitoring of athletes if a timeframe for the re-equilibration of vascular volumes is respected.
Stability of hemoglobin mass during a 6-day UCI ProTour cycling race.Garvican LA, Eastwood A, Martin DT, Ross ML, Gripper A, Gore CJ.: Clinical Journal of Sport Medicine, 2010, 20(3):200-4 Language: eng Country: United States Department of Physiology, Australian Institute of Sport, Canberra, Australia. Objective: Blood doping in endurance sport is a growing problem. The purpose of this study was to determine the reliability of total hemoglobin mass (Hb(mass)) measurement in the field and to establish the variability of Hb(mass) during a cycling race, to assess its viability as an additional antidoping detection parameter. Design: Control-matched longitudinal study. Setting: International Cycling Union's (UCI) ProTour stage race. Participants: Six professional cyclists and 5 recreationally active controls. Interventions: Seventy-two Hb(mass) tests using the optimized carbon monoxide rebreathing method were performed over 7 consecutive days, before and throughout the tour. Fasted venous blood was obtained for measurement of hematocrit (Hct) and hemoglobin concentration [Hb] in the morning before stages 1, 3, and 6 (D1, D3, and D6). Main Outcome Measures: Reliability of Hb(mass) measurement was established using typical error calculated from 2 baseline measures. Individual change scores and coefficients of variation were used to assess stability during racing. Results: Typical error for Hb(mass) was 1.3% [95% confidence limits (CL): 0.9%, 2.5%]. Calculated 95% and 99.99% CL for percent change in Hb(mass) were +/-3.6% and +/-7.2%, respectively. Mean Hb(mass) remained within +/-1.9% of baseline in cyclists and +/-0.5% in controls. In all cases, individual change scores for both cyclists and controls fell within the 95% CL. There was a decrease in Hct (8.1% +/- 2.8%) and [Hb] (9.7% +/- 3.2%) throughout the tour in cyclists but not in controls. Conclusions: We demonstrate that Hb(mass) can be measured reliably via CO-rebreathing during a cycling tour. Unlike [Hb] and Hct, Hb(mass) remains stable over 6 days of racing in professional cyclists and may have potential in an antidoping context.
The utility of immature reticulocyte fraction as an indicator of erythropoietic response to altitude training in elite cyclists.Nadarajan VS, Ooi CH, Sthaneshwar P, Thompson MW.: International Journal oF laboratory Hematology, 2010, 32(1 Pt 2):82-7 . Department of Pathology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. Altitude training is sometimes employed by elite endurance athletes to improve their sea level performance. This improvement Results from the increased red cell mass consequent upon the boost in erythropoietin (EPO) level that occurs as a response to the relatively hypoxic environment at high altitudes. We measured serum EPO levels together with various red cell and reticulocyte parameters including immature reticulocyte fraction (IRF) in eight national track-endurance cyclists, resident at sea-level, prior to and upon return from an altitude of approximately 1905 m. Reticulocytes and soluble transferrin receptor (sTfR) were significantly increased with reduction in ferritin levels immediately on return from high altitude indicating increased erythropoietic activity. IRF in particular showed a significant peak immediately on return but decline to sub-baseline levels by day 9, and recovery to baseline by day 16. Our Results indicate that IRF is a sensitive marker of erythropoietic status in athletes undergoing altitude training and subsequent loss of EPO stimuli on return to sea level.
Reticulocyte profile in top-level alpine skiers during four consecutive competitive seasons.Banfi G, Tavana R, Freschi M, Lundby C.: European Journal of Applied Physiology, 2010, 109(3):561-8. IRCCS Galeazzi and School of Medicine, University of Milan, Milan, Italy. The role of reticulocytes (Ret) in Sports medicine became clear when the count of immature erythrocytes was introduced in protocols used for anti-doping purposes. Because specific research regarding seasonal variations in Ret is lacking, we assessed Ret (and [Hb]) in top-level male and female skiers during four consecutive competitive seasons. A difference (P < 0.05) between males and females was found for [Hb] and Ret values: [Hb] was lower and Ret was higher in females. The difference was maintained across all four competitive seasons. Marked within-subject differences in [Hb], Ret and immature reticulocyte fraction values were noted; the within-subject variability was greater than the between-subject variability in both genders. For instance, a difference for Ret was consistently shown between first and second blood drawings, i.e. between basal value, before the start of training and competition, and the value at middle of season, when training workload was at highest level. Unlike Ret%, the analysis of variance showed significant changes in [Hb] values across competitive seasons for both genders. Comparison between consecutive seasons (e.g., 2005-2006 vs. 2006-2007) showed significant differences for both parameters. The behaviour of [Hb] and Ret during the various seasons was parallel in females, whereas a discrepancy existed in males. In general, inter-individual variability is quite high, thus, Ret and [Hb] modifications should be referred only to the single athlete. We confirm the validity of the use of Ret counts for anti-doping purposes. Elite athletes' perceptions of the effects of illicit drug use on athletic performance.Thomas JO, Dunn M, Swift W, Burns L.: Clinical Journal of Sport Medicine,2010, 20(3):189-92. National Drug and Alcohol Research Centre, University of New South Wales, Sydney, New South Wales 2052, Australia. Objective: To investigate the perceived risks and benefits that elite athletes associate with illicit drugs and their beliefs concerning the effects of recreational drug use on athletic performance. Design: Self-administered survey. Participants: Nine hundred seventy-four elite athletes (mean age, 23 years; range, 18-30 years) were recruited from 8 national sporting organizations in Australia and the Australian Institute of Sport. Interventions: Participants completed a self-administered survey that included questions exploring participants' perceptions regarding the effects of illicit drug use on physical performance. Setting: National sporting organization meetings or competitions. Main Outcome Measures: The main outcome measure was risk perception on athletic performance associated with illicit drug use. Results: The majority of athletes believed that illicit drug use would impact negatively on athletic performance. The main perceived effects of illicit drugs on athletic performance were physical and mental functioning. A minority of athletes indicated that drug use would not impact on physical performance when taken during the off-season or in moderation. Conclusions: The main risks perceived in association with illicit drug use were short-term consequences, such as physical and mental functioning, rather than long-term health consequences. The current findings may contribute to the development of harm reduction strategies that communicate drug-related consequences to elite athletes in an appropriate and effective manner.
Sports doping in the adolescent: the Faustian conundrum of Hors de Combat.Greydanus DE, Patel DR.: Pediatric Clinics of North America, 2010-06 57(3):729-50. Department of Pediatrics & Human Development, Michigan State University College of Human Medicine, Kalamazoo, MI 49008-1284, USA. The drive toward success in sports and the need for a cosmetically acceptable appearance have driven many adolescents to take a wide variety of so-called doping substances. The consumption of these chemicals in the hope and hype of improved sports performance, fueled by the easing of government restrictions on their proof of safety and efficacy, has resulted in an explosion of so-called ergogenic products available to our youth. Agents that have been used include anabolic steroids, anabolic-like agents, designer steroids, creatine, protein and amino acid supplements, minerals, antioxidants, stimulants, blood doping, erythropoietin, beta-blockers, and others. The use of these agents has considerable potential to cause physical and psychological damage. Use and misuse of drugs in this sports doping process should be discouraged. This discussion reviews some of the agents that are currently being used. Clinicians providing sports medicine care to youth, whether through anticipatory guidance or direct sports medicine management, should educate their young patients about the hype and hyperbole of these products that may keep them out instead of in the game at considerable financial cost to the unwary consumer.
Doping use among young elite cyclists: a qualitative psychosociological approach.Lentillon-Kaestner V, Carstairs C.: Scandinavian Journal of Medicine & Science in Sports, 201004 20(2):336-45. Institute of Sport and Physical Education Sciences, University of Lausanne, Lausanne, Switzerland. Using a psychosociological approach, the purpose of this study was to identify and understand the use of doping substances by young elite cyclists. Semi-structured interviews were conducted with young cyclists who were hoping to find a professional team and cyclists who had recently become professional. All of the young cyclists interviewed took nutritional supplements and believed that they improved their performance, which has been shown by other scholars to be a risk factor for doping. These cyclists believed that doping at the professional level in cycling was acceptable but did not approve of it at the amateur level. They were attracted to doping; they were open to using doping substances themselves if it was the key to continuing their cycling career, but only after they became professional. Team staff, doctors, parents and friends helped to create a "clean" environment that prevented the young cyclists from doping before becoming professional. The more experienced cyclists, who doped or used to dope, transmitted the culture of doping to the young cyclists, teaching them doping methods and which substances to use. This study could help to improve prevention and help to detect doping, as it is clear that doping behaviors begin at the amateur level.
Gene doping: the hype and the harm.McKanna TA, Toriello HV.: Pediatric Clinics of North America, 2010-06 57(3):719-27. Spectrum Health Genetic Services, Grand Rapids, MI 49503, USA. "Gene doping" is the term used to describe the potential abuse of gene therapy as a performance-enhancing agent. Gene doping would apply the techniques used in gene therapy to provide altered expression of genes that would promote physical superiority. For example, insulin-like growth factor 1 (IGF-1) is a primary target for growth hormone; overexpression of IGF-1 can lead to increased muscle mass and power. Although gene doping is still largely theoretical, its implications for sports, health, ethics, and medical genetics are significant.
Is human growth hormone an ergogenic aid?Holt RI.: Drug Testing and Analysis, 2009, 1(9-10):412-8. Endocrinology and Metabolism Sub-Division, Developmental Origins of Health and Disease Division, School of Medicine, University of Southampton, UK. Growth hormone (GH) was first isolated from the pituitary gland in the 1940s. It is believed that athletes have been abusing GH for its anabolic and lipolytic effects since the early 1980s, at least a decade before endocrinologists began to treat adults with GH deficiency. Most of our knowledge about GH abuse is anecdotal but a number of high-profile athletes have admitted using GH. Despite its widespread abuse, there is debate about whether GH is ergogenic. Indeed most scientific studies have not shown a performance enhancing effect. This review will address why this discrepancy of opinion between athletes and scientists exists and why the author believes that the scientists are wrong.
Anti-doping testing at the 2008 European football championship.Vouillamoz M, Thom C, Grisdale R, Saugy M, Giraud S, Robinson N, Gmeiner G, Geisendorfer T. Drug Testing and Analysis, 2009, 1(11-12):485-93. Union des Associations Europeénnes de Football, Nyon, Switzerland. Big sports events like the 2008 European Football Championship are a challenge for anti-doping activities, particularly when the sports event is hosted by two different countries and there are two laboratories accredited by the World Anti-Doping Agency. This challenges the logistics of sample collection as well as the chemical analyses, which must be carried out timeously. The following paper discusses the handling of whereabouts information for each athlete and the therapeutic use exemption system, experiences in sample collection and transportation of blood and urine samples, and the results of the chemical analysis in two different accredited laboratories. An overview of the analytical results of blood profiling and growth hormone testing in comparison with the distribution of the normal population is also presented.
Pseudoephedrine ingestion and cycling time-trial performance.Pritchard-Peschek KR, Jenkins DG, Osborne MA, Slater GJ.: International Journal of Sport Nutrition and Exercise Metabolism, 2010, 20(2):132-8. University of Queensland, Brisbane, Australia. The aim of the current study was to investigate the effect of 180 mg of pseudoephedrine (PSE) on cycling time-trial (TT) performance. Six well-trained male cyclists and triathletes (age 33 +/- 2 yr, mass 81 +/- 8 kg, height 182.0 +/- 6.7 cm, VO2max 56.8 +/- 6.8 ml x kg(-1) x min(-1); M +/- SD) underwent 2 performance trials in which they completed a 25-min variable-intensity (50-90% maximal aerobic power) warm-up, followed by a cycling TT in which they completed a fixed amount of work (7 kJ/kg body mass) in the shortest possible time. Sixty minutes before the start of exercise, they orally ingested 180 mg of PSE or a cornstarch placebo (PLA) in a randomized, crossover, double-blind manner. Venous blood was sampled immediately pre- and postexercise for the analysis of pH plus lactate, glucose, and norepinephrine (NE). PSE improved cycling TT performance by 5.1% (95% CI 0-10%) compared with PLA (28:58.9 +/- 4:26.5 and 30:31.7 +/- 4:36.7 min, respectively). There was a significant Treatment x Time interaction (p = .04) for NE, with NE increasing during the PSE trial only. Similarly, blood glucose also showed a trend (p = .06) for increased levels postexercise in the PSE trial. The ingestion of 180 mg of PSE 60 min before the onset of high-intensity exercise improved cycling TT performance in well-trained athletes. It is possible that changes in metabolism or an increase in central nervous system stimulation is responsible for the observed ergogenic effect of PSE. Pilot study of serum inhibin B as a potential marker of testosterone doping in weight lifting men.Barthel A, Bornstein SR, Benker G.: Clinical Journal of sport Medicine : official Journal of the Canadian Academy of Sport Medicine, 201003 20(2):117-9. Endokrinologikum Ruhr, Bochum, Germany. Objective: The aim of this study was to explore effectors of the pituitary-testicular axis suitable as potential biochemical markers to screen for testosterone doping. Design: Pilot study with male bodybuilding athletes with a self-reported history of testosterone doping (repeated intramuscular administration of testosterone preparations, last injection 8 weeks or less ago) compared with an equal sized control group matched for sex, age, and body mass index. Setting: Endocrine outpatients. Participants: Fifteen healthy young men of white background. Interventions : None. Main outcome measures: Inhibin B, testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH). Results: Although the levels of testosterone, LH, and FSH did not differ between the 2 groups, the serum concentrations of inhibin B in individuals with a history of testosterone doping were exclusively at or below the lower limit of the normal range for adult men (100-400 pg/mL). Inhibin B was significantly lower in those men who used testosterone for weight lifting (76.1 +/- 36.3 ng/L [mean +/- SD]) than in controls (182.1 +/- 35.4 ng/L). Conclusion: A low concentration of serum inhibin B may reflect the application of exogenous testosterone and appears to be a potential marker associated with anabolic androgenic steroid doping.
Caffeine does not augment markers of muscle damage or leukocytosis following resistance exercise.Machado M, Koch AJ, Willardson JM, dos Santos FC, Curty VM, Pereira LN.: International Journal of Sports Physiology and Performance, 201003 5(1):18-26. Laboratory of Physiology and Biokinetic (UNIG Campus V), Itaperuna, Brazil. Purpose: The Purpose of this study was to evaluate the effects of caffeine ingestion before a resistance exercise session on markers of muscle damage (CK, LDH, ALT, AST) and leukocyte levels. Methods: Fifteen soccer athletes completed two resistance exercise sessions that differed only in the ingestion of caffeine or a placebo preworkout. Results: CK concentration increased significantly following the caffeine session (415.8+/-62.8 to 542.0+/-73.5) and the placebo session (411.5+/-43.3 to 545.8+/-59.9), with no significant differences between sessions. Similarly, LDH concentration increased significantly following the caffeine session (377.5+/-18.0 to 580.5+/-36.1) and the placebo session (384.8+/-13.9 to 570.4+/-36.1), with no significant differences between sessions. Both sessions resulted in significant increases in the total leukocyte count (caffeine=6.24+/-2.08 to 8.84+/-3.41; placebo=6.36+/-2.34 to 8.77+/-3.20), neutrophils (caffeine=3.37+/-0.13 to 5.15+/-0.28; placebo=3.46+/-0.17 to 5.12+/-0.24), lymphocytes (caffeine=2.19+/-0.091 to 2.78+/-0.10; placebo=2.17+/-0.100 to 2.75+/-0.11), and monocytes (caffeine=0.53+/-0.02 to 0.72+/-0.06; placebo=0.56+/-0.03 to 0.69+/-0.04), with no significant differences between sessions. Conclusion: Ingestion of caffeine at 4.5 mg/kg(-1) did not augment markers of muscle damage or leukocyte levels above that which occurs through resistance exercise alone.
Dose response of caffeine on 2000-m rowing performance.Skinner TL, Jenkins DG, Coombes JS, Taaffe DR, Leveritt MD.: Medicine and Science in Sports and Exercise, 201003 42(3):571-6. The University of Queensland, School of Human Movement Studies, Queensland, Australia. Purpose: To determine whether a dose-response relationship exists between caffeine and 2000-m rowing performance. Methods: In this randomized, placebo-controlled, double-blind crossover study, 10 competitive male rowers (mean +/- SD: age = 20.6 +/- 1.4 yr, body mass = 87.7 +/- 10.5 kg, height = 186.8 +/- 6.8 cm, (.)VO2peak = 5.1 +/- 0.6 L x min(-1)) consumed 2, 4, or 6 mg x kg(-1) caffeine or a placebo 60 min before completing a 2000-m time trial on a rowing ergometer. The trials were preceded by a 24-h standardized diet (including a light preexercise meal of 2 g x kg(-1) CHO), and subjects were tested preexercise for hydration, caffeine abstinence, and blood glucose concentrations. Results: Time trial performance was not significantly different across the three caffeine doses or placebo (P = 0.249). After the three caffeine trials, postexercise plasma glucose and lactate concentrations were higher compared with the placebo trial (P < 0.05). Plasma caffeine concentrations after 60 min of ingestion were lower than the values reported previously by others following the same dose, and there was considerable interindividual variation in plasma caffeine concentrations in response to the various caffeine doses. Conclusions : The large interindividual response to the caffeine doses suggests that individual characteristics need to be considered when administering caffeine for performance enhancement. In addition, preexercise feeding may significantly affect plasma caffeine concentrations and the potential for caffeine to improve performance.
No effect of prior caffeine ingestion on neuromuscular recovery after maximal fatiguing contractions.Fimland MS, Helgerud J, Knutsen A, Ruth H, Leivseth G, Hoff J.: European Journal of Applied Physiology, 2010, 108(1):123-30. Department of Circulation and Imaging, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway. The Purpose of this study was to test the hypothesis that prior caffeine ingestion would enhance neural recovery after isometric fatiguing maximal intermittent plantar flexions, and thus would enhance the recovery of voluntary muscle strength. After a familiarisation session, 13 males randomly participated in two experimental trials where they ingested either caffeine (approximately 6 mg/kg) or identical placebo pills 1 h prior to testing. Subjects were tested for electromyogram (EMG) activity and evoked V-waves in the soleus and gastrocnemius medialis muscles. These measurements were obtained during brief plantar flexion maximum voluntary isometric contractions (MVICs), and normalised by the superimposed maximal M-wave (EMG/M(SUP) and V/M(SUP), respectively), before and after (20 s, 10 min and 20 min) a fatigue protocol (seven 25 s MVICs, 5 s rest). There were no effects (P > 0.05) of caffeine ingestion on EMG/M(SUP), V/M(SUP), MVIC or M(SUP). The central neural modulation (EMG/M(SUP) and V/M(SUP)) and voluntary strength changes followed a similar time-course with a substantial reduction 20 s post-fatigue and a gradual return towards baseline values.
Anabolics and cardiomyopathy in a bodybuilder: case report and literature review.Ahlgrim C, Guglin M.: Journal of Cardiac Failure, 2009, 15(6):496-500. University of South Florida, Tampa, FL, USA. Background: Athletes use androgenic-anabolic steroids to increase strength and muscle mass. Several case reports suggest that it may lead to dilated cardiomyopathy. Methods and results: We report a case of a 41-year-old bodybuilder with severe systolic dysfunction and Class IV heart failure despite maximal medical therapy. He used anabolic steroids and insulin growth factor, and did not have any other risk factors for cardiomyopathy. We briefly review the literature and summarize other reported cases with similar scenarios. In most of them cardiomyopathy was at least partially reversible after discontinuation of anabolics. Conclusions: Abuse of anabolic steroids may be an uncommon cause of cardiomyopathy in young and otherwise healthy individuals.
Dehydroepiandrosterone to enhance physical performance: myth and reality.Hahner S, Allolio B.: Endocrinology and Metabolism Clinics of North America, 2010, 39(1):127-39, x. Department of Medicine I, University of Würzburg, Würzburg, Germany. Dehydroepiandrosterone (DHEA) is secreted by the zona reticularis of the adrenal cortex and is converted into potent sex steroids in peripheral target cells. As oral DHEA administration can lead to dose-dependent increases in circulating androgens, which may reach high supraphysiologic levels in women, it has been included in the list of prohibited substances by the World Anti-Doping Agency (WADA). However, evidence for an ergogenic activity of DHEA is still largely nonexistent. Randomized trials in elderly subjects with an age-dependent decrease in DHEA have provided little or no evidence for enhanced physical performance after long-term administration of DHEA, 50 mg/d, and smaller short-term studies in healthy male athletes using higher doses were completely negative. Thus the widely perceived performance-enhancing activity of DHEA is still more myth than reality. However, because studies in female athletes are still lacking, an ergogenic activity of high-dose DHEA in this population cannot be excluded but is expected to be associated with adverse events like hirsutism, acne, and alopecia.
Ergogenic effects of inhaled beta2-agonists in non-asthmatic athletes.Wolfarth B, Wuestenfeld JC, Kindermann W.: Endocrinology and Metabolism Clinics of North America. 2010, 39(1):75-87, ix. Department of Preventive and Rehabilitative Sports Medicine, Technical University Munich, Munich, Germany. The potential ergogenic effects of asthma medication in athletes have been controversially discussed for decades. The prevalence of asthma is higher in elite athletes than in the general population. The highest risk for developing asthmatic symptoms is found in endurance athletes and swimmers. In addition, asthma seems to be more common in winter-sport athletes. Asthmatic athletes commonly use inhaled beta2-agonists to prevent and treat asthmatic symptoms. However, beta2-agonists are prohibited according to the "Prohibited List of the World Anti-Doping Agency" (WADA). Until the end of 2009 an exception was only allowed for the substances formoterol, salbutamol, salmeterol, and terbutaline by inhalation, as long as a so-called therapeutic use exemption has been applied for and was granted by the relevant anti-doping authorities. From 2010 salbutamol and salmeterol are allowed by inhalation requiring a so called declaration of use.
Glucocorticoids: a doping agent?Duclos M.: Endocrinology and Metabolism Clinics of North America, 2010, 39(1):107-26, ix-x. Department of Sport Medicine and Functional Explorations, University-Hospital (CHU), Hôpital G. Montpied, Clermont-Ferrand, France. Certain international sports federations are requesting that glucocorticoids (GCs) be removed from the World Antidoping Agency's list of banned products. Their arguments are based on the fact that GCs are in widespread use in sports medicine and have no demonstrated ergogenic activity. This article shows that there is scientific evidence that GCs mediate ergogenic effects in animals and humans. Moreover, the health risks of using GCs are well characterized. GCs are doping agents and should remain on the World Antidoping Agency's list of banned products. |