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Background: One factor that may negatively impact male reproductive health is the illegal use of testosterone and anabolic-androgenic steroids. This study aimed to evaluate the prevalence of testosterone use in recreational athletes, as well as factors associated with its use, and to determine the profile of a person using testosterone. Methods: A cross-sectional analysis of data from an anonymous, online questionnaire of men recruited from gyms, randomly selected in Wroclaw, Poland, has been performed. The minimal sample size was evaluated with the univariate logistic regression model. The association between testosterone use and other factors was also evaluated with the univariate logistic regression model. Results: A total of 35% of respondents used testosterone. The main purposes of testosterone use were the improvement of training effects and the improvement of body shape. The respondents most likely to use testosterone and other anabolic-androgenic steroids were men aged 26-35, whose earnings were at the level of the middle class or higher, who were married, had children, had training experience of at least 6 months, exercised at least once a week, took part in weightlifting competitions, were managers in a corporation or enterprise, or were self-employed. Most of the people using testosterone had self-treated side effects. Conclusions: The profile of the person most likely to use testosterone corresponds to the characteristics of men in optimal socio-demographic conditions for reproduction. These results indicate that this is a significant social problem that may impact male reproductive health.
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PURPOSE: This study aimed to determine whether the initial levels of aerobic fitness and hematological variables in young female road cyclists are related to their athletic performance development during their careers. METHODS: Results of graded exercise tests on a cycle ergometer and total hemoglobin mass (tHb-mass) measurements were analyzed in 34 female road cyclists (age 18.6 [1.9] y). Among them, 2 groups were distinguished based on their competitive performance (Union Cycliste Internationale world ranking) over the following 8 years. Areas under the curve in receiver-operating-characteristic curves were calculated as indicators of elite-performance prediction. RESULTS: Initial graded exercise test variables (peak power, peak oxygen uptake, and power at 4 mmol/L blood lactate) were not significantly different in elite (n = 13) versus nonelite (n = 21) riders. In contrast, elite riders had higher tHb-mass expressed either in absolute measures (664 [75] vs 596 [59] g, P = .006) or normalized to body mass (11.2 [0.8] vs 10.3 [0.7] g/kg, P = .001) and fat-free mass (14.4 [0.9] vs 13.1 [0.9] g/kg, P < .001). Absolute and relative erythrocyte volumes were significantly higher in elite subjects (P ranged from < .001 to .006). Of all the variables analyzed, the relative tHb-mass had the highest predictive ability to reach the elite level (area under the curve ranged from .82 to .85). CONCLUSION: Measurement of tHb-mass can be a helpful tool in talent detection to identify young female road cyclists with the potential to reach the elite level in the future.
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Rendimiento Atlético , Ciclismo , Prueba de Esfuerzo , Hemoglobinas , Consumo de Oxígeno , Humanos , Femenino , Ciclismo/fisiología , Rendimiento Atlético/fisiología , Adolescente , Adulto Joven , Hemoglobinas/análisis , Hemoglobinas/metabolismo , Ácido Láctico/sangre , Aptitud Física/fisiología , Curva ROCRESUMEN
This narrative review provides an overview of scientific studies on dietary supplements that may affect circulating testosterone (T) levels to explore which substances are scientifically proven to increase T concentration. We also review the scientific literature for their potential mechanisms and laboratory test changes triggered by their use. Based on the analysis of existing data on substances used to increase endogenous T levels, especially double-blind placebo-controlled randomized clinical trials, we selected 2 herbal extracts with the best documented positive effects on T levels, Withania somnifera root and root extracts/leaves and seed extracts of Trigonella foenum-graecum. Although these substances have different postulated mechanisms of action, both significantly increase T levels in men. Withania somnifera may inhibit the effects of cortisol and prolactin on the hypothalamic-pituitary-gonadal axis and directly affect the hypothalamus. Trigonella foenum-graecum seeds contain the active substance diosgenin, which is a precursor for sex hormone synthesis in gonads.
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Exercise-induced metabolic processes induce muscle acidification which contributes to a reduction in the ability to perform repeated efforts. Alkalizing agents such as sodium bicarbonate (NaHCO3) prevent large blood pH changes, however, there is no evidence on whether regulation of acid-base balance may also support whole body homeostasis monitored through heamatological and biochemical blood markers in a dose-dependent manner. Thirty Cross-Fit-trained participants were studied in a randomized, multi cross-over, placebo (PLA)-controlled double-blind manner in which they performed a control session (CTRL, without supplementation), three NaHCO3 visits (three different doses) and PLA (sodium chloride in an equimolar amount of sodium as NaHCO3). Each visit consisted of two 30-s Wingate tests separated by CrossFit-specific benchmarks (Wall Balls and Burpees - both performed for 3 min). Blood samples were collected at rest, immediately post-exercise and after 45 min recovery. Significant differences between visits appeared for blood pH, percentage of lymphocytes and granulocytes, red blood cells count and haemoglobin concentration at post-exercise and 45-min recovery, and for white blood cells count, percentage of monocytes, concentration of magnesium and creatinine at 45-min recovery. Most of the observed differences for heamatological and biochemical markers were significant compared to CTRL, but not different after PLA. NaHCO3 supplementation compared to PLA did not significantly affect exercise or recovery shifts in studied blood indicators. However, the changes in these markers after NaHCO3 and PLA in relation to CTRL indicate a possible role of sodium.
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PURPOSE: Selective androgen receptor modulators (SARMs) have demonstrated agonist activity on the androgen receptor in various tissues, stimulating muscle mass growth and improving bone reconstruction. Despite being in clinical trials, none has been approved by the Food and Drug Administration (FDA) or European Medicines Agency for pharmacotherapy. Still, SARMs are very popular as performance-enhancing drugs. The FDA has issued warnings about the health risks associated with SARMs, but the long-term exposure and possible adverse events still need to be fully understood. This review aims to evaluate the adverse events associated with using SARMs by humans. METHODS: PubMed database was searched from September 16, 2022, to October 2, 2023. In total, 20 records were included in the final review. Data from preclinical and clinical studies supported the review. RESULTS: Since 2020, 20 reports of adverse events, most described as drug-induced liver injury associated with the use of SARM agonists, have been published. The main symptoms mentioned were cholestatic or hepatocellular liver injury and jaundice. Limited data are related to the dosages and purity of SARM supplements. CONCLUSION: Promoting SARMs as an anabolic agent in combination with other performance-enhancing drugs poses a risk to users not only due to doping controls but also to health safety. The lack of quality control of consumed supplements makes it very difficult to assess the direct impact of SARMs on the liver and their potential hepatotoxic effects. Therefore, more detailed analyses are needed to determine the safety of using SARMs.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Enfermedades Musculares , Sustancias para Mejorar el Rendimiento , Humanos , Receptores Androgénicos , Andrógenos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiologíaRESUMEN
Endurance performance is positively associated with hematological adaptations; therefore, high total hemoglobin mass and intravascular volumes are commonly observed in high-level endurance athletes. However, it is still unclear whether the fluctuations in exercise capacity that typically occur in endurance athletes during the annual training cycle are directly associated with changes in hematological adaptations, which appear to be relatively stable during this time. To better understand this issue, a study was conducted with 10 Olympic rowers, who followed the same training program. Athletes underwent laboratory testing in the competitive and the general preparation phase of an annual training cycle (a 34% reduction in training volume). This included a graded exercise test on a rowing ergometer (GXT) and blood measurements of hemoglobin concentration (Hb), total hemoglobin mass (tHb-mass), plasma volume (PV), and blood volume (BV). Decreases in maximal values of power relative to body mass (p = 0.028), lactate concentration (p = 0.005), and heart rate (p = 0.017) in the GXT were registered. At the same time, absolute (p = 0.017) and relative (p = 0.005) PV decreased. Changes in PV (rS = 0.842, p = 0.002) and BV (rS = 0.818, p = 0.004), but not in tHb-mass (rS = 0.588, p = 0.074) and Hb (rS = -0.188, p = 0.602), were significantly correlated with changes in maximal power in the GXT. Our results indicate a close relationship between changes in intravascular volumes and maximal exercise capacity after a period of reduced training loads in elite endurance athletes.
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COVID-19 , Deportes , Vacunas , Humanos , COVID-19/prevención & control , Atletas , Deportes/fisiologíaRESUMEN
(1) Background: The purpose of this study was to investigate the concerns and beliefs of Olympians and elite athletes toward COVID-19 vaccination. (2) Methods: The study was framed by a quantitative method and was conducted using the PAPI (pen and paper interview) technique among 895 Polish elite athletes representing 34 sports. (3) Results: Three-quarters (76.3%) of the athletes were vaccinated against COVID-19; statistically participants were more likely to be women, and athletes who participated in the Olympic Games. Four in ten (39.2%) were in favor of vaccination. Athletes were mainly concerned that COVID-19 would exclude them from training/competition (19.3%) and could have a long-term impact on their health (17.2%). Athletes who were vaccinated reported much higher confidence in the composition of the vaccine and the doctors who recommended vaccination than unvaccinated athletes. Athletes who competed at the Olympic level were more likely than others to disbelieve that vaccines were produced too quickly and were not well tested. National-level athletes showed the highest degree of distrust in the government regarding COVID-19 vaccination, with one in six respondents distrusting doctors with respect to COVID-19 vaccination. Four in ten respondents said they were in favor of vaccination. (4) Conclusions: Athletes' attitudes toward COVID-19 vaccination were significantly influenced by their environment-especially coaches and relatives. The power of social norms with respect to the decision to vaccinate against COVID-19 was very strong. Therefore, it is essential to build awareness about preventive policies among athletes and their social environment.
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OBJECTIVES: To determine the number of training days lost due to COVID-19 and vaccination against COVID-19 in elite athletes. DESIGN: Retrospective cohort study. METHODS: The questionnaire on the impact of vaccination and COVID-19 on training plans was filled out by 1073 elite Polish athletes who underwent routine medical screening between September and December 2021. RESULTS: COVID-19 was diagnosed in 421 subjects (39â¯%), of whom 26â¯% were asymptomatic. On the 10-point scale, <1â¯% of athletes had perceived severity of the disease above 8, whereas for 64â¯% it was 4 or below. Vaccination against COVID-19 was administered in 820 athletes (76â¯%), and adverse events were observed more frequently after the first dose than the second (69â¯% vs. 47â¯%). Influence on training (modified or lost) was declared by 369 of 421 (88â¯%) COVID-19 athletes, and by 226 of 820 vaccinated athletes (28â¯%). During the observation period, the average number of lost training days was 8.1 for COVID-19 and 2.6 for vaccination (pâ¯<â¯0.001). The cumulative number of person-days lost due to COVID-19 was 1041 versus 295 after vaccination thus, the average loss ratio was 1041/1073â¯=â¯0.97 vs. 295/820â¯=â¯0.36, respectively, pâ¯<â¯0.01. CONCLUSIONS: Athletes have a considerable loss of training days due to COVID-19. Vaccination against COVID-19 causes significantly smaller and predictable loss. This supports the inclusion of vaccination into prevention policies for athletes whenever they are available.
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COVID-19 , Vacunas , Humanos , COVID-19/prevención & control , Estudios Retrospectivos , Atletas , PolíticasRESUMEN
OBJECTIVES: The aim of the study was to identify predictors determining the course of COVID-19 and antibody response in elite athletes. DESIGN: Observational study. METHODS: Routine medical screening with physical examination, resting ECG, and laboratory tests including antibody response was performed 12-68â¯days after the diagnosis of COVID-19 in 111 athletes of different sports. RESULTS: Clinical symptoms were observed in 84% of subjects. The severity of COVID-19 was mild in 82% of athletes and moderate in 2% of cases. Athletes aged above 26 and male were more likely to develop symptomatic COVID-19. Asymptomatic subjects were younger and predominantly female. In 18% of subjects, symptoms were still present 20 (12-68) days (median and range) since positive diagnosis. Antibody response was observed in 88% of athletes, and its magnitude correlated with time since diagnosis of COVID-19 (RT-PCR), fatigue, fever, and conjunctivitis. There were no differences in antibody response between groups distinguished by sports discipline (pâ¯=â¯0.50), and sex (pâ¯=â¯0.59), and antibody response did not correlate with BMI (pâ¯=â¯0.12), age (pâ¯=â¯0.13), the number of symptoms (pâ¯=â¯0.43) or their duration (pâ¯=â¯0.19). CONCLUSIONS: The severity of COVID-19 in elite athletes is predominantly mild and without complications. Athletes can return to sport after two symptom-free weeks and additional heart screening is usually not required. Determination of antibodies has been shown to be a useful indicator of a previous COVID-19 disease, and some symptoms can be used as predictors of antibody response.
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COVID-19 , Anciano , Atletas , Femenino , Humanos , Masculino , Tamizaje Masivo , SARS-CoV-2RESUMEN
The use of specific medicine up to several months before a doping control is not be reported on the doping control form, while the drug could then still be detectable in urine in case of a very slow elimination. It may lead to a positive test result. For example, dorzolamide, a carbonic anhydrase inhibitor for topical ophthalmic application, has a very slow elimination rate via the renal route (half-life > 4 months). This substance can be a source of unintended anti-doping rule violations.
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Inhibidores de Anhidrasa Carbónica/administración & dosificación , Doping en los Deportes/prevención & control , Sulfonamidas/administración & dosificación , Tiofenos/administración & dosificación , Administración Oftálmica , Adulto , Inhibidores de Anhidrasa Carbónica/farmacocinética , Femenino , Semivida , Humanos , Sulfonamidas/farmacocinética , Tiofenos/farmacocinética , Factores de TiempoRESUMEN
OBJECTIVE: The aim of the study was to evaluate the safety and tolerance of influenza vaccines for the northern and southern hemispheres in Polish elite athletes participating in the Rio 2016 Olympics. DESIGN: Prospective, observational, cohort study. SETTING: Institutional level. PARTICIPANTS: Ninety-seven athletes vaccinated only with the northern hemisphere vaccine; 98 athletes received the southern hemisphere vaccine alone, whereas 39 athletes were vaccinated with both vaccines. INTERVENTIONS: The athletes were vaccinated with a trivalent, inactivated influenza vaccine recommended for the northern hemisphere 2015/2016 and then with the vaccine recommended for the southern hemisphere 2016. Athletes kept a diary of adverse events and effects (if any) on training for 6 days after vaccination. MAIN OUTCOME MEASURES: The percentage of general and local adverse events, number of lost or modified training sessions. RESULTS: Significantly more local adverse events (pain and redness) were found in the group immunized with the vaccine for the northern hemisphere. There were no differences in the frequency of general adverse events and influence on training between groups. Of total 273 athletes who had 1911 training days during 6 days after vaccination, 6 athletes (2.2%) lost 13 training days (0.7%) and 16 athletes (5.9%) had to modify 34 (1.7%) training days within first 2 days after vaccination. CONCLUSIONS: Athletes tolerated influenza immunization well. If they are going to travel to the other hemisphere during the influenza season, the use of the second influenza vaccine should be advised. Athletes should anticipate modification of trainings for 2 days after vaccination.
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Atletas , Vacunas contra la Influenza , Gripe Humana , Humanos , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/uso terapéutico , Gripe Humana/prevención & control , Polonia , Estudios ProspectivosRESUMEN
Vitamin D is a nutrient whose active form affects tissues as a hormone and possibly enhances performance. One plausible mechanism is by increasing testosterone concentration, which is established as an important factor for athletic performance. Therefore the aim of the study was to examine the relationship between plasma concentration of 25(OH)D and testosterone in Polish elite track and field athletes depending on vitamin D status, season, training period, body composition, sex, type of training, sun exposure and vitamin D supplementation. Plasma concentrations of 25(OH)D and testosterone were measured in all seasons within two years in athletes (70 females, 79 males) who represent strength (n = 103) and endurance (n = 46) kinds of sports, in the preparatorycompetitive season and transition period. There were no differences in 25(OH)D concentration between male and female athletes, insufficiency [25(OH)D < 30 ng/ml] was observed in 32.9%, whereas deficiency [25(OH)D < 20 ng/ ml] in 3.2%. Circannual rhythm was noted for vitamin D but not for testosterone concentration; no correlations between them were found either in strength or endurance athletes or between 25(OH)D and body composition. Testosterone concentration was higher in the transition period than in the preparatory-competition period only in male athletes. Higher 25(OH)D was observed in athletes who trained during winter in Africa (higher sun exposure) or used oral supplementation, whereas the respective testosterone levels were unchanged. In athletes, testosterone concentration did not reflect vitamin D status. The widespread of inadequate vitamin D status among athletes, makes it vital to recommend them the regular monitoring of 25(OH)D concentration and use of reasonable supplementation.
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BACKGROUND: Athletes and coaches believe in the ergogenic effect of vitamin B12 (which results from enhanced erythropoiesis) and they often insist on its unjustified supplementation. Therefore, our study aimed to assess the vitamin B12 status in Polish elite athletes and its influence on red blood cell parameters. METHODS: In total, 1131 blood samples were collected during six years from 243 track and field athletes divided into strength and endurance groups, as well as according to the declared use of vitamin B12 injections. RESULTS: An average vitamin B12 concentration in all subjects was 739 ± 13 pg/mL, with no cases of deficiency. A weak but significant relationship was found between vitamin B12 and hemoglobin concentrations. A significant increase in hemoglobin appeared from very low vitamin B12 concentration and up to approx. 400 pg/mL, while hemoglobin did not significantly change from 700 pg/mL and onwards. Vitamin B12 injections were used by 34% of athletes, significantly more often by endurance than by strength athletes. In athletes who declared no use of injections, a higher concentration of vitamin B12 was observed in the endurance group. CONCLUSION: The main finding of the present study is the determination of the range of vitamin B12 concentration which may favor better hemoglobin synthesis in athletes. They should regularly monitor vitamin B12 concentration and maintain the range of 400-700 pg/mL as it may improve red blood cell parameters. We might suggest application of a supplementation if necessary. Special attention is required in athletes with a vitamin B12 concentration below 400 pg/mL.
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Atletas , Hemoglobinas/metabolismo , Fenómenos Fisiológicos de la Nutrición/fisiología , Resistencia Física/efectos de los fármacos , Vitamina B 12/administración & dosificación , Vitamina B 12/sangre , Adulto , Femenino , Humanos , Inyecciones , Masculino , Resistencia Física/fisiología , Polonia , Vitamina B 12/farmacología , Adulto JovenRESUMEN
Orysiak, J, Witek, K, Malczewska-Lenczowska, J, Zembron-Lacny, A, Pokrywka, A, and Sitkowski, D. Upper respiratory tract infection and mucosal immunity in young ice hockey players during the pretournament training period. J Strength Cond Res 33(11): 3129-3135, 2019-The aim of this study was to determine the effects of 17 days of training during preparation for the Ice Hockey Under 18 World Championship of the Polish ice hockey national team on the mucosal immune function and monitor upper respiratory tract infection (URTI) incidence before, during, and after the competition. Twelve male ice hockey players (age, 17.7 ± 0.5 years) were recruited for this study. The first saliva and blood collection took place at the beginning of the training camp (without training at the training camp), the second one was collected on the 9th day of the training camp immediately after the intensification of training, and the third collection was performed on the 13th day of training (4 days before leaving for the World Championship) in the tapering phase. To assess the mucosal immune function, concentrations of secretory immunoglobulin A (sIgA), sIgA1, and sIgA2 were analyzed in saliva. Cortisol concentration and creatine kinase activity were determined in blood, as indicators of stress and muscle damage, respectively. The Wisconsin Upper Respiratory Symptom Survey-21 questionnaire was used to assess URTI symptoms. A significant increase in the sIgA1 and sIgA2 concentrations was observed in the third collection compared with the second time point (114.45 ± 33.00 vs. 77.49 ± 27.29 and 88.97 ± 25.33 vs. 71.65 ± 32.44 U, respectively). There were no statistically significant correlations between the URTI incidence and saliva variables. In conclusion, the tapering period positively affects the mucosal immune function, especially sIgA1 and sIgA2 concentrations, with no significant change in the frequency of URTI in young ice hockey players.
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Hockey/fisiología , Inmunidad Mucosa , Inmunoglobulina A Secretora/metabolismo , Acondicionamiento Físico Humano/fisiología , Infecciones del Sistema Respiratorio/inmunología , Adolescente , Creatina Quinasa/sangre , Humanos , Hidrocortisona/sangre , Incidencia , Masculino , Saliva/metabolismo , Encuestas y Cuestionarios , Evaluación de SíntomasRESUMEN
Exercise-induced respiratory symptoms describe acute airway narrowing that occurs as a result of exercise. It includes exercise-induced bronchoconstriction (EIB) and exercise-induced asthma (EIA) issues. To provide clinicians with practical guidelines, a multidisciplinary panel of stakeholders was convened to review the pathogenesis of EIB/EIA and to develop evidence-based guidelines for the diagnosis and treatment. Recommendations for the diagnosis and treatment of EIB were developed. High-intensity exercise in polluted environment (cold air, humidity, contamination, allergens) may increase the risk of EIB and asthma symptoms in athletes. Diagnostic procedures should include history taking, physical examination, atopy assessment and functional tests of the respiratory system. A strong recommendation was made for regular use of inhaled glucocorticosteroids and avoidance of short-acting ß2-agonists as the only treatment. The treatment of asthma in athletes should always take into account current anti-doping regulations. This position paper reflects the currently available evidence.
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In this study, GC-MS- and MEKC-based methods for determination of caffeine (CAF) in preworkout supplements were developed and validated. The proposed protocols utilized minimal sample preparation (simple dilution and syringe filtration). The developed methods achieved satisfactory validation parameters, i.e. good linearity (R2 > 0.9988 and R2 > 0.9985 for GC-MS- and MEKC-based method, respectively), satisfactory intra- and interaccuracy (within 92.6-100.7% for method utilizing GC-MS and 92.1-110.3% for protocol based on MEKC) and precision (CV < 15.9% and CV < 6.3% for GC-MS- and MEKC-based method, respectively) and recovery (within 100.1-100.8% for method utilizing GC-MS and 101.5-106.2% for protocol based on MEKC). The LOD was 0.03 and 3 µg/mL for method utilizing GC-MS and MEKC, respectively. The CAF concentrations determined by GC-MS- and MEKC-based methods were found to be in the range of 8.53-11.23 and 8.20-11.61 µg/mL, respectively. Taking into consideration information on the labels, the investigated supplements were found to contain from 110.0 to 167.3% of the declared CAF content, which confirmed the literature reports on incompatibility of the declared product compositions with real ones. Nevertheless, the consumption of examined supplements as recommended by producers did not lead to exceeding the CAF safe limit of 400 mg per day. Additionally, the MEKC-based method allowed for detection and identification of vitamin B3 and B6 in all of the investigated supplement samples, which demonstrated that MEKC-based protocols may be an appropriate assays for simultaneous determination of CAF and vitamins.
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Cafeína/análisis , Cromatografía Capilar Electrocinética Micelar/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Vitaminas/análisis , Suplementos Dietéticos/análisis , Escala de Lod , Niacinamida/análisis , Vitamina B 6/análisisRESUMEN
The benefits of altitude/hypoxic training for sea level performance are still under debate. This study examined the effects of low altitude training supported by normobaric hypoxia on hematological status and endurance performance predictors in elite female cyclists. Twenty-two female cyclists trained for 3 weeks at low altitude (<1100 m) and 2 weeks near sea level. During the first 3 weeks, 15 subjects stayed in hypoxic rooms simulating an altitude of 2200 m (+NH group, n = 8) or 1000 m (placebo group, n = 7), and 7 (control group) stayed in regular rooms. Significant increases in total hemoglobin mass (tHb-mass: p = 0.008, p = 0.025), power at 4 mmol·l-1 lactate (PAT4: p = 0.004, p = 0.005) (in absolute and relative values, respectively) and maximal power (PF: p = 0.034) (in absolute values) were observed. However, these effects were not associated with normobaric hypoxia. Changes in tHb-mass were not associated with initial concentrations of ferritin or transferrin receptor, whereas changes in relative tHb-mass (r = -0.53, p = 0.012), PF (r = -0.53, p = 0.01) and PAT4 (r = -0.65, p = 0.001) were inversely correlated with initial values. Changes in tHb-mass and PAT4 were positively correlated (r = 0.50, p = 0.017; r = 0.47, p = 0.028). Regardless of normobaric hypoxia application, low altitude training followed by sea-level training might improve hematological status in elite female cyclists, especially with relatively low initial values of tHb-mass, which could translate into enhanced endurance performance.
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Being frequent travelers, the elite athletes are advised to undergo an influenza vaccination. The aim of the study was to describe the antibody response to repeated trivalent, inactivated, split influenza vaccine, of different antigenic content, recommended for the Northern and the Southern Hemisphere, administered to sportsmen before the Olympic Games in Brasil in 2016. Fourteen athletes were included in the study. For both A/California/7/209/pdm09 A/H1N1/ antigen and A/Switzerland/971593/2013/A/H3N2/ antigen, higher seroconversion rates were obtained after the first than the second vaccination (10.2 vs. 1.5 and 10.6 vs. 3.0, respectively; p < 0.05 both). Conversion rates for B/Phuket/3073/2013, B/Brisbane/60/2008, and A/HongKong/4801/2014/A/H3N2/ antigens were lower. Nonetheless, the protection rate was greater than 70% for all antigens contained in both vaccines. The proportion of individuals demonstrating a high level of both protection rate and response rate was greater after the first than the second vaccination. We conclude that the immunological response after influenza vaccination is good in elite athletes and remains so after a second influenza vaccination required due to a different vaccine composition recommended for different hemispheres.
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Anticuerpos Antivirales/sangre , Atletas , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Formación de Anticuerpos , Humanos , Subtipo H1N1 del Virus de la Influenza A , Subtipo H3N2 del Virus de la Influenza A , Vacunas contra la Influenza/uso terapéuticoRESUMEN
Interrelationships between physiological changes (Δ) in erythropoietin (EPO), plasma volume (PV), haemoglobin concentration ([Hb]), and total haemoglobin mass (tHb-mass) were examined in cyclists who trained in different altitudes. Regardless of differences in pattern of changes observed in three training locations, ΔEPO was correlated positively with ΔPV, negatively with Δ[Hb], and trivially with ΔtHb-mass. Δ[Hb] was negatively correlated with ΔPV. In the pooled data the Spearman's rank correlation coefficients were as follows: r = 0.783, P < 0.001; r = -0.704, P < 0.001; r = 0.136, P > 0.05; r = -0.813, P < 0.001, respectively. The obtained results have shown that EPO does not only regulate [Hb] by erythropoiesis stimulation but also by PV modulation, which probably aims at keeping proper level of arterial oxygen content for oxygen delivery to tissues.