Article

Is Testosterone Influencing Explosive Performance?

March 2006
The Journal of Strength and Conditioning Research 20(1):103-7

DOI:10.1519/R-16864.1

Source
PubMed

Authors:

Marco Cardinale

Aspetar - Qatar Orthopaedic and Sports Medicine Hospital

Michael Henry Stone

East Tennessee State University

The primary objective of this study was to analyze the relationship between testosterone levels and vertical jumping performance in elite men and women athletes. The secondary objective was to verify whether testosterone levels and vertical jumping performance were different in men and women athletes and if those measurements were different between different athletic groups. Seventy (22 women and 48 men) elite athletes in track and field (sprinters), handball, volleyball, and soccer competing at national and international levels participated in the study. After 10 hours of fasting and 1 day of rest, blood samples were drawn from the antecubital vein for determining testosterone levels. Vertical jumping tests consisted of countermovement jumps conducted on a resistive platform connected to a digital timer. Resting testosterone levels in women were 9.5% of those of the men (respectively 0.62 +/- 0.06 ng.ml(-1) and 6.49 +/- 0.37 ng.ml(-1); p < 0.001). Countermovement jump performance was significantly different between women and men athletes, with women's jumping ability 86.3% of that of men (p < 0.001). A significant positive relationship was identified between testosterone levels and vertical jump performance when all data where considered (r = 0.61, p < 0.001, n = 70).

Homeorresis generizadas: las diferencias atléticas conceptualizadas desde una perspectiva materialista no biologicista

Article

Full-text available

Aug 2022

Lucia Ciccia

En este trabajo busco problematizar la idea acerca de que la actual distribución binaria en el desempeño atlético se debe a las diferencias en los niveles de testosterona. Específicamente, estos darían cuenta de la mayor proporción de masa muscular magra, densidad ósea y concentraciones de hemoglobina que, a su vez, explicarían tal distribución con la consecuente ventaja masculina. En contrapartida, desarrollo hipótesis explicativas que reinterpreten las diferencias promedio en los parámetros mencionados y el rendimiento deportivo en el marco de las normativas de género. Así, empleo la noción de homeorresis para referirme a los procesos fisiológicos complejos mediante los cuales nuestros organismos se estabilizan. Considero que los mismos pueden reflejar materializaciones moleculares que resultan de nuestras prácticas generizadas. Tal materialización, sugiero, puede implicar que, en torno a la idea de valores de referencia, estemos asumiendo naturales ciertas diferencias biológicas que hoy se observan entre varones cis y mujeres cis. En cambio, voy a proponer que se tratan de valores promedio estandarizados desde interpretaciones androcéntricas biologicistas, y que suponen estados deficitarios crónicos para las mujeres cis. Concluyo que lo que puede un cuerpo se encuentra delineado por un discurso testo-céntrico, es decir, centrado en la testosterona, que interactúa con nuestros estados psicológicos/biológicos. Una interacción que implica encarnar sucesos nocebo para los cuerpos feminizados que participan en ámbitos masculinizados, como lo es el deporte de competencia.

Hormonal Responses and Jump Performance Across a Season in Collegiate Women Basketball Players

Article

Jan 2021

The testosterone-to-cortisol ratio (T/C) has been shown to be positively correlated with strength and power. However, few studies have examined the relationship between a standardized power performance measurement and T/C throughout a season of intercollegiate competition. The purpose of this study was to examine the relationships between salivary T/C and vertical jump (VJ) performance of female National Collegiate Athletic Association Division II basketball players across a season. Saliva samples were taken before practice, weekly, for a total of 29 weeks. Samples were assayed for testosterone (T) and cortisol (C). After saliva collection, players completed two countermovement VJs, with the best jump used for data analysis. A positive correlation between T/C and VJ was seen only during the preseason phase. Statistically significant differences were observed across the season for T/C and VJ. T/C in the nonconference phase was significantly lower than the preseason phase and the late-conference phase, p = .013 and p = .047, respectively. VJ was significantly lower in the late-conference phase when compared to the preseason and nonconference phases, p < .001 and p = .026, respectively. VJ in the early-conference phase was also significantly lower than the preseason phase, p < .001. These data support the literature that has indicated a positive relationship between the T/C and lower-body power but only in the preseason phase. This relationship reverses and trends toward a negative relationship, before disappearing in the second half of the season. Monitoring T/C may provide value in assessing female athletes’ performance potential in the preseason phase. T/C should be interpreted with more caution once the competitive season begins.

Is testosterone responsible for athletic success in female athletes?

Preprint

Feb 2019

The aim of this study is to determine the interrelationship between the resting serum T levels (an inherited trait) of female athletes from different types of sporting events and their athletic success. The study involves 599 Russian international-level female athletes (95 highly elite, 190 elite, and 314 sub-elite) and 298 age-matched female controls. All subjects were age 16-35 years old and to the best of our knowledge have always tested negative for performance enhancing substances. The athlete cohort was stratified into four groups according to event duration, distance, and type of activity: 1) endurance athletes, 2) athletes with mixed activity, 3) speed/strength athletes, and 4) sprinters. Athletic success was measured by determining the level of achievement of each athlete. The mean (SD) T levels of athletes and controls were 1.65 (0.87) and 1.76 (0.6) nmol/L (P=0.057) with ranges of 0.08-5.80 and 0.38-2.83 nmol/L in athletes and controls, respectively. No significant differences in T levels were found between different groups of athletes. T levels were positively correlated (r=0.62, P<0.0001) with athletic success in sprinters (runners, cyclists, kayakers, speed skaters, swimmers). Moreover, none of the sub-elite sprinters had T > 1.9 nmol/L, while 50% of elite and highly elite sprinters had T > 1.9 nmol/L (95% CI: 2.562-862.34; OR=47.0; P<0.0001). We do not observe the benefits of having high T levels for success in other groups of athletes. Conversely, highly elite middle-distance (P=0.235) and mixed activity athletes (P=0.096) tended to have lower T levels than less successful athletes. Our data suggest that the measurement of the serum T levels significantly correlates with athletic success in sprinters but not other types of athletes and in the future may be useful in the prediction of sprinting ability.

Gestion stratégique de la charge d’entraînement en rugby à 7 pour l’optimisation de la performance physique en compétition

Thesis

Full-text available

Oct 2018

Resting Hormone Alterations and Injuries: Block vs. DUP Weight-Training among D-1 Track and Field Athletes

Article

Full-text available

Jan 2018

Daily undulating periodization (DUP), using daily alterations in repetitions, has been advocated as a superior method of resistance training, while traditional forms of programming for periodization (Block) have been questioned. Nineteen Division I track and field athletes were assigned to either a 10-week Block or DUP training group. Year and event were controlled. Over the course of the study, there were four testing sessions, which were used to evaluate a variety of strength characteristics, including maximum isometric strength, rate of force development, and one repetition maximum (1RM). Although, performance trends favored the Block group for strength and rate of force development, no statistical differences were found between the two groups. However, different (p ≤ 0.05) estimated volumes of work (VL) and amounts of improvement per VL were found between groups. Based upon calculated training efficiency scores, these data indicate that a Block training model is more efficient in producing strength gains than a DUP model. Additionally, alterations in testosterone (T), cortisol (C) and the T:C ratio were measured. Although there were no statistically (p ≤ 0.05) different hormone alterations between groups, relationships between training variables and hormone concentrations including the T:C ratio, indicate that Block may be more efficacious in terms of fatigue management.

Performance Comparisons of Youth Weightlifters as a Function of Age Group and Sex

Article

Full-text available

Jun 2021

This study was designed to provide an overview of weightlifting performance as a function of age group and sex and evaluate the potential of countermovement jump height (CMJH) as a tool to gauge performance potential. Data from 130 youth athletes (female, n = 65 & male, n = 65) were used to examine progression of performance (Total and Sinclair total) and the relationship between CMJH and Sinclair total while considering interactions between CMJH and age and/or sex. ANOVAs with post hoc analyses revealed that both totals had a statistical first-order polynomial interaction effect between age group and sex and the difference between age groups of 12-13 and 14-15 years old was statistically greater for male than female. A linear model, developed to examine the relationship, revealed that CMJH and CMJH x sex x age rejected the null hypothesis. Our primary findings are that male youth weightlifters have a higher rate of performance progression, possibly owing to puberty, and CMJH may be a better gauging tool for older male youth weightlifters.

An Intramuscular Injection of Mixed Testosterone Esters Does Not Acutely Enhance Strength and Power in Recreationally Active Young Men

Article

Full-text available

Sep 2020

Purpose: Limited data are available on the acute performance-enhancing effects of single-dose administration of testosterone in healthy humans. Studies of testosterone administrations to healthy humans are rare due to the difficult nature and necessity of close clinical monitoring. However, our unique physiological experimental facilities combined with close endocrinological collaboration have allowed us to safely complete such a study. We tested the hypothesis that an intramuscular injection of 250 mg mixed testosterone esters (TEs) enhances physical performance in strength and power exercises acutely, measured 24 h after injection. Additionally, we investigated whether the basal serum testosterone concentration influences the performance in countermovement jump (CMJ), 30-s all out cycle sprint, and one-arm isometric elbow flexion. Methods: In a randomized, double-blind, placebo-controlled design, 19 eugonadal men received either a TE (n = 9, 23 ± 1 years, 183 ± 7 cm, 83 ± 10 kg) or a PLA (n = 10, 25 ± 2 years, 186 ± 6 cm, 82 ± 14 kg) injection. Hormonal levels and the performance in CMJ, 30-s all out cycle sprint, and one-arm isometric elbow flexion were measured before and 24 h after injection. Results: Firstly, an intramuscular injection of 250 mg mixed TEs did not enhance the vertical jump height in a CMJ test, peak power, mean power, and fatigue index in a 30-s all-out cycle sprint or rate of force development and maximal voluntary contraction in a one-arm isometric elbow flexion 24 h post-injection. Secondly, baseline testosterone levels appeared not to influence performance in strength and power exercises to a large extent in healthy, recreationally active young men. Conclusion: A single intramuscular injection of 250 mg mixed TEs has no acute ergogenic effects on strength and power performance in recreationally active, young men. This novel information has implication for basic physiological understanding. Whether the same applies to an elite athlete population remains to be determined. If so, this would have implications for anti-doping efforts aiming to determine the most cost-efficient testing programs.

Improving time- and cost-efficiency in doping analysis

Thesis

Dec 2019

Sara Amalie Solheim

Testosterone esters and clenbuterol are among the most frequently used doping substances in elite and recreational sports. Direct detection in urine and blood samples is hampered by the costs of collection, transportation and analysis, and the rapid hydrolysis of testosterone esters in blood. Indirect detection of testosterone by the ‘Athlete Biological Passport’ (ABP) steroidal module is limited by both the associated costs and confounding factors. Therefore, the present thesis aimed to improve the time- and cost-efficiency in doping analysis by evaluating 1) the applicability of dried blood spots (DBS) as a complementary sample matrix and 2) whether the hematological module of the ABP can be used to indicate doping of testosterone and thereby increase detection, given the erythropoietic effect of testosterone, and 3) by determining the most cost-efficient anti-doping testing program based on detection windows and performance-enhancing effects. In Paper I-III, DBS, urine and blood samples from men receiving two intramuscular injections of Sustanon® 250 (n = 9) or placebo (n = 10) in a randomized, placebo-controlled design were analyzed for direct and indirect detection of testosterone esters and assessment of serum levels of reproductive hormones. In Paper III, the performances in countermovement jump, 30-s all out cycle sprint and one-arm isometric elbow flexion were measured before and 24 h after the first Sustanon® injection. In Paper IV, DBS and urine samples from 6 healthy men receiving a single oral dose of 80 µg clenbuterol were collected and analyzed for detection of clenbuterol. Paper II and IV demonstrated that the DBS assays allow for detection up to 14 days after an intramuscular injection of 250 mg Sustanon®, and for at least 3 days after an oral ingestion of 80 µg clenbuterol, with 100% specificity. Further, preliminary data suggest that DBS-sampling is well accepted by athletes. Additionally, Paper IV showed that clenbuterol can be detected for at least 10 days in urine after ingestion of 80 µg of drug. Paper I demonstrated that some hematological biomarkers are affected by testosterone administration, and that the largest changes occur 3-10 days after an injection. Paper III showed that a single injection of testosterone esters do not enhance human performance acutely in a countermovement jump test, a one-arm isometric elbow flexion test nor a 30-sec cycle sprint test. In conclusion, the DBS analyses of testosterone esters and clenbuterol appear to have sufficient specificity and sensitivity to be implemented in routine doping control in elite and recreational sports. Given the longer detection windows for clenbuterol in urine, urine is expected to remain as the preferred sample matrix for clenbuterol analysis. However, the implementation of DBS sampling could improve time- and costefficiency while reducing intrusiveness, and thereby allow for higher frequency of testing, or testing of a large number of athletes in a short time, with the aim of increasing detection and deterrence. Further, changes in markers in the hematological module could be indicative of testosterone doping, and should be considered an additional tool for targeted follow-up sample collection and confirmatory analysis. Moreover, since testosterone did not have any acute performance-enhancing effects in power/strength exercises, athletes are likely not to have an advantage if administering a single dose of testosterone esters immediately before or during a competition in power/strength sports. ISBN 978-87-7209-334-5

PAPEL DA TESTOSTERONA NO DESEMPENHO DE POTÊNCIA DE JOGADORES PROFISSIONAIS DE FUTEBOL EM DIFERENTES MOMENTOS DA TEMPORADA COMPETITIVA

Article

Full-text available

Nov 2018

Os objetivos do presente estudo foram: 1) verificar a associação entre a testosterona (T) e o desempenho de potência (P) de membros inferiores de jogadores profissionais de futebol durante uma temporada competitiva; e 2) verificar o efeito da alteração da concentração de T entre o início e o final da temporada competitiva na variação de P. No início (M1) e no final (M2) de uma temporada competitiva de 8 semanas, 12 jogadores profissionais de futebol forneceram amostras de saliva e realizaram salto vertical com contramovimento com carga adicional de 30% do peso corporal. Foi observada manutenção da concentração de T e diminuição de P para o grupo como um todo (p

Papel da testosterona no desempenho e potência de jogadores profissionais de futebol em diferentes momentos da temporada competitiva

Article

Full-text available

Jul 2018

Papel da testosterona no desempenho de potência de jogadores profi ssionais de futebol em diferentes momentos da temporada competitiva Role of testosterone on power performance in professional soccer players at different periods of the competitive season ARRUDA AFS, SARGENTIM S, AOKI MS, MOREIRA A. RESUMO: Os objetivos do presente estudo foram: 1) verifi car a associação entre a testosterona (TEST) e o desempenho de potência de membros inferiores de jogadores profi ssionais de futebol durante uma temporada competitiva; e 2) verificar o efeito da alteração da concentração de TEST entre o início e o fi nal da temporada competitiva na variação da potência. No início (M1) e no fi nal (M2) de uma temporada competitiva de 8 semanas, 12 jogadores profi ssionais de futebol forneceram amostras de saliva e realizaram salto vertical com contramovimento com carga adicional de 30% da massa corporal. Foi observada manu-tenção da concentração de TEST e diminuição de potência para o grupo como um todo (p<0,05). Quando separados dois subgrupos de acordo com a resposta de TEST, o subgrupo com diminuição da concentração de TEST (DCT) teve redução no desempenho de potência. Já o subgrupo com aumento da concentração de TEST (ACT) manteve o desempenho de potência alcançado em M1. Também foi verifi cada correlação signifi cativa e positiva entre a concentração de TEST e o desempenho de potência em M1 e M2 (r = 0,68 e 0,87, respectivamente), assim como, entre a variação de TEST e a variação de potência de M1 para M2, tanto para a potência média (r = 0,75), quanto para a potência relativa (0,77), para o subgrupo ACT. A partir da separação do grupo de acordo com a alteração de TEST do M1 para M2, foi possível observar diferentes respostas de desempenho de potência. O subgrupo ACT manteve o nível de potência durante a temporada competitiva. Esses resultados sugerem que o aumento de TEST durante a temporada competitiva pode estar associado à manutenção de potência em jogadores profi ssionais de futebol. Palavras-chave: Esporte coletivo; Saliva; Treinamento esportivo; Monitoramento; Salto vertical. ABSTRACT: The main aims of the present study were: 1) to examine the influence of testosterone (TEST) on lower limbs power performance during a competitive season in professional soccer players; and 2) to observe the effect of TEST change on power response. At the beginning (M1) and the end (M2) of an 8-week competitive season, 12 professional soccer players provided saliva samples and performed countermovement jumps with a 30% of their body mass load. It was observed no significant change in TEST, and a decrement in power performance, for the whole group (p<0.05). However, when the group was divided into subgroups, the subgroup that showed a decrement in TEST concentration (DTC) from M1 to M2 presented a decrease in power performance; conversely, the subgroup that presented an increment in TEST concentration (ITC) was able to maintain the previous level of power. A significant and positive correlation between TEST concentration and power for both M1 and M2 (r = 0.68 and 0.87), as well as between TEST variation and power change from M1 to M2 (r = 0.75 for mean power, and 0.77 for relative mean power was only observed for the ITC subgroup. Different responses were observed in lower limbs power performance according to TEST concentration change from M1 to M2. The ITC subgroup maintained power performance during the competitive season. These results suggest that an increase in TEST during the competitive season may improve the likelihood of maintaining power performance in professional soccer players.

The complex and bidirectional interaction between sex hormones and exercise performance in team sports with emphasis on soccer

Article

Jun 2019

A constant topic reported in the lay press is the effect of sex hormones on athletic performance and their abuse by athletes in their effort to enhance their performance or to either boost or sidestep their hard, protracted, and demanding training regimens. However, an issue that it is almost never mentioned is that the athletic training itself affects the endogenous production of androgens and estrogens, while also being affected by them. Among sports, soccer is a particularly demanding activity, soccer players needing to possess high levels of endurance, strength, and both aerobic and anaerobic capacity, with the very great physiological, metabolic, physical, and psychological exertion required of the players being both influenced by sex steroids and, reciprocally, affecting sex steroid levels. This review focuses on the currently available knowledge regarding the complex relationship between athletic training and competition and sex steroid hormone adaptation to the demands of the exercise effort. In the first part of the review, we will examine the effects of endogenous testosterone, estrogen, and adrenal androgens on athletic performance both during training and in competition. In the second part, we will explore the reciprocal effects of exercise on the endogenous sex hormones while briefly discussing the recent data on anabolic androgenic steroid abuse.

Biological relation and the predictive possibilities between the morpho-functional and the voice-acoustic parameters

Article

Jun 2019

BACKGROUND: Since the human being functions as a multidimensional system with highly adaptable automatic features and with strong correlations among the subsystems, the scientists have been encouraged to explore the predictive possibilities of one human characteristic/ability according to different morpho-functional characteristics/abilities. The goal of this study was to explore the biological relations between morpho-functional variables and the voice-acoustic parameters, and the possibility to predict the explosive power of the lower extremities based on the registered voice acoustic parameters. METHODS: Seven morpho-functional variables and six voice-acoustic parameters were measured on 37 male athletes aged 15-29 years. The statistical analysis was accomplished through the SPSS-program version-20 and Statistica-12. The obtained data were analyzed through Canonical Analyses, Regressive Analyses, and t-test for Paired Samples. RESULTS: Canonical analysis has enabled the extraction of one significant canonical root (P=0.043), which explains 73.7% of the shared variance. The results of the regression analysis indicate that the system of voice-acoustic parameters significantly predicts 34.7% of total variance of the criterion variable Margarita-Kalamen test. CONCLUSIONS: The final results of this study confirm very close biological relations between morpho-functional and voice-acoustic parameters. Additionally, according to these results, it might be suggested that based on the voice-acoustic parameters: MeanF0 and MinF0, may be predicted the athlete’s explosive power of the lower extremities.

Is testosterone responsible for athletic success in female athletes?

Preprint

Full-text available

Feb 2019

The aim of this study is to determine the interrelationship between the resting serum testosterone (T) levels (an inherited trait) of female athletes from different types of sporting events and their athletic success. The study involves 599 Russian international-level female athletes (95 highly elite, 190 elite, and 314 sub-elite) and 298 age-matched female controls. All subjects were age 16-35 years old and to the best of our knowledge have always tested negative for performance enhancing substances. The athlete cohort was stratified into four groups according to event duration, distance, and type of activity: 1) endurance athletes, 2) athletes with mixed activity, 3) speed/strength athletes, and 4) sprinters. Athletic success was measured by determining the level of achievement of each athlete. The mean (SD) T levels of athletes and controls were 1.65 (0.87) and 1.76 (0.6) nmol/L (P=0.057) with ranges of 0.08-5.80 and 0.38-2.83 nmol/L in athletes and controls, respectively. No significant differences in T levels were found between different groups of athletes. T levels were positively correlated (r=0.62, P<0.0001) with athletic success in sprinters (runners, cyclists, kayakers, speed skaters, swimmers). Moreover, none of the sub-elite sprinters had T > 1.9 nmol/L, while 50% of elite and highly elite sprinters had T > 1.9 nmol/L (95% CI: 2.562-862.34; OR=47.0; P<0.0001). We do not observe the benefits of having high T levels for success in other groups of athletes. Conversely, highly elite middle-distance (P=0.235) and mixed activity athletes (P=0.096) tended to have lower T levels than less successful athletes. Our data suggest that the measurement of the serum T levels significantly correlates with athletic success in sprinters but not other types of athletes and in the future may be useful in the prediction of sprinting ability.

Is testosterone responsible for athletic success in female athletes?

Experiment Findings

Feb 2019

Ildus I. Ahmetov

Sport, doping and female fertility

Article

Full-text available

Nov 2018
REPROD BIOL ENDOCRIN

Abstract This article is a review that addresses the following topics, divided by paragraphs. The first paragraph investigates the effects of physical activity on ovarian function, analyzing in particular the changes concerning the serum concentrations of follicle-stimulating hormone, luteinizing hormone, prolactin, growth hormone, thyroid hormones, leptin, ghrelin, neuropeptide Y. The second paragraph analyzes the effects of doping on the hypothalamic-pituitary-ovarian axis. Finally, the last paragraph analyzes the PCOS category, evaluating the effects of hyperandrogenism in relation to athletic performance.

Circulating Testosterone as the Hormonal Basis of Sex Differences in Athletic Performance

Article

Full-text available

Jul 2018

Elite athletic competitions have separate male and female events due to men’s physical advantages in strength, speed and endurance so that a protected female category with objective entry criteria is required. Prior to puberty, there is no sex difference in circulating testosterone concentrations or athletic performance but from puberty onwards sex difference in athletic performance emerges as circulating testosterone concentrations rise in men because testes produce 30 times more testosterone than before puberty with circulating testosterone exceeding 15-fold those of women at any age. There is a wide sex difference in circulating testosterone concentrations and reproducible dose-response relationship between circulating testosterone and muscle mass and strength as well as circulating hemoglobin in both men and women. These dichotomies largely accounts for the sex differences in muscle mass and strength and circulating hemoglobin levels resulting in at least an 8-12% ergogenic advantage in men. Suppression of elevated circulating testosterone of hyperandrogenic athletes results in negative effects on performance, which are reversed when suppression ceases. Based on the non-overlapping, bimodal distribution of circulating testosterone concentration (measured by liquid chromatography-mass spectrometry) and making allowance for women with mild hyperandrogenism including that of polycystic ovarian syndrome, who are over-represented in elite athletics, the appropriate eligibility criterion for female athletic events should be a circulating testosterone of less than 5.0 nmol/L. This would include all women other than those with untreated hyperandrogenic disorders of sexual development (DSD), testosterone-treated female-to-male (F2M) transgender, noncompliant male-to-female (M2F) transgender or androgen doping.

Static Posture Assessment Screen of Athletes: Benefits and Considerations

Article

Oct 2008

EFFETS DE LA CHARGE DE TRAVAIL SUR LA PERFORMANCE ET LES CARACTÉRISTIQUES PHYSIOLOGIQUES DE RUGBYMEN PROFESSIONNELS. ETUDE LONGITUDINALE

Thesis

Full-text available

Dec 2017

Romain Dubois

L’objectif de ce travail de thèse était (i) de quantifier la charge de travail (CT) et son évolution au cours de la saison, et (ii) d’étudier ses effets sur la performance, les qualités physiques, le risque de blessures, les caractéristiques psychologiques et biochimiques de rugbymen à XV professionnels. En premier lieu, nous nous sommes intéressés à la quantification de la demande métabolique lors de matchs officiels de hautniveaux (étude 1). Les principaux résultats de cette étude montrent que l’approche de la puissance métabolique constitue une alternative à l’approche traditionnelle pour quantifier les efforts de course de haute intensité. En second lieu, une étude préliminaire (étude 2) a permis d’étudier les évolutions de CT (GPS & RPE), des qualités physiques et des caractéristiques biochimiques, tout au long d’une saison chez des joueurs arrières. Un deuxième protocole expérimental (études 3 & 4) a permis de compléter les résultats de l’étude 2, en analysant notamment l’influence de CT sur l’évolution des caractéristiques psychologiques, du taux de blessures et de la performance en match. Les études 2, 3 et 4 montrent que CT est significativement (p < 0.05) plus élevée pendant la première partie de la saison (pré-saison et début du championnat). Ces études montrent également que la CT compétitive et le nombre d’impacts sévères (>8G) sont les principaux paramètres de CT influençant les réponses physiologiques des joueurs. Ces paramètres influencent les caractéristiques psychologiques, les marqueurs des dommages musculaires (CK) et le nombre de duels gagnés en compétition. Ces études montrent aussi qu’un volume d’entraînement élevé associé à une faible intensité d’entraînement influencent négativement les performances neuromusculaires (Tests DJ et CMJ). Enfin, l’addition d’entraînements avec contacts et l’accumulation de CT compétitive peut favoriser l’apparition d’un état de fatigue avancée (surcharge non-fonctionnelle), illustrée par une diminution significative (p < 0.05) des ratios T/C et IGF-1/C.

Low Second-to-Fourth Digit Ratio has High Explosive Power? A Prepubertal Study

Article

Jan 2018

A recent study reported that lower limb explosive power had no correlation with the 2D:4D ratio. However, many studies hypothesized that a lower 2D:4D ratio (reflecting a relative higher testosterone exposure) predicts higher physical fitness. The aim of this study is to replicate the study of explosive power and the 2D:4D ratio in a sample of Taiwanese children. A total of 541 Taiwanese prepubertal children (257 girls and 284 boys aged 9-10 years) participated in this study. This study analyzed the relationship between the 2D:4D ratio and explosive power. Explosive power of the lower limbs was assessed using the standing long jump (SLJ) test. The lengths of the second and fourth fingers of the right hand were measured to calculate the 2D:4D ratio. The SLJ length was correlated with the 2D:4D ratios (r = - 0.144, p = 0.015) in boys. After controlling for age and the BMI, this correlation remained significant (r = - 0.134, p = 0.024). For girls, 2D:4D ratios were not significantly correlated with SLJ scores. These results indicate the SLJ distance was negatively correlated with the 2D:4D ratio in boys, but not in girls. These findings might suggest PT exposure is negatively correlated with the explosive power in males, but not in females.

The Participation of Trans Women in Competitive Fencing and Implications on Fairness: A Physiological Perspective Narrative Review

Article

Full-text available

Jul 2023

Debate has surrounded whether the participation of trans women in female sporting categories is fair, specifically the retained male physiological advantage due to increased testosterone compared to cisgender females. Recently, individual sporting organisations have been investigating and assessing policies regarding trans women athlete participation in female categories, resulting in several banning participation. This review aims to discuss the scientific evidence and provide appropriate guidance for the inclusion of trans women in elite competitive female fencing categories. Fencing is an intermittent sport, where competitions can span 1 to 3 days. The lunge is the most common movement used to attack opponents, where a successful hit relies on the speed of the action. Male puberty induced increased circulating testosterone promotes a greater stature, cardiovascular function, muscle mass, and strength compared to cisgender females, culminating in a ~12–40% sport performance advantage. Elite cisgender male fencers perform significantly higher, ~17–30%, jump heights and leg power measures compared to elite cisgender female fencers, resulting in faster lunges. Trans women receiving androgen-suppression therapy for 12 months showed significant reductions in strength, lean body mass, and muscle surface area, but even after 36 months, the measurements of these three indices remained above those for cisgender females. Previous male muscle mass and strength can be retained through continuation of resistance training. The literature reviewed shows that there is a retained physiological advantage for trans women who have undergone male puberty when participating in the elite competitive female fencing category. A proposed solution of an open or third gender category for elite fencing competition promotes fair competition, while allowing trans women to compete in their chosen sport.

Acute effects of concurrent muscle power and sport-specific endurance exercises on markers of immunological stress response and measures of muscular fitness in highly trained youth male athletes

Article

Full-text available

Jan 2023
EUR J APPL PHYSIOL

Purpose To examine the acute effects of concurrent muscle power and sport-specific endurance exercises order on immunological stress responses, muscular-fitness, and rating-of-perceived-exertion (RPE) in highly trained youth male judo athletes. Methods Twenty male participants randomly performed two concurrent training (CT) sessions; power-endurance and endurance-power. Measures of immune response (e.g., white blood cells), muscular-fitness (i.e., counter-movement-jump [CMJ]), RPE, blood-lactate, and -glucose were taken at different time-point (i.e., pre, mid, post, and post6h). Results There were significant time*order interactions for white blood cells, lymphocytes, granulocytes, granulocyte-lymphocyte-ratio, and systemic-inflammation-index. Power-endurance resulted in significantly larger pre-to-post increases in white blood cells and lymphocytes while endurance-power resulted in significantly larger pre-to-post increases in the granulocyte-lymphocyte-ratio and systemic-inflammation-index. Likewise, significantly larger pre-to-post6h white blood cells and granulocytes increases were observed following power-endurance compared to endurance-power. Moreover, there was a significant time*order interaction for blood-glucose and -lactate. Following endurance-power, blood-lactate and -glucose increased from pre-to-mid but not from pre-to-post. Meanwhile, in power-endurance blood-lactate and -glucose increased from pre-to-post but not from pre-to-mid. A significant time*order interaction was observed for CMJ-force with larger pre-to-post decreases in endurance-power compared to power-endurance. Further, CMJ-power showed larger pre-to-mid performance decreases following power-endurance, compared to endurance-power. Regarding RPE, significant time*order interactions were noted with larger pre-to-mid values following endurance-power and larger pre-to-post values following power-endurance. Conclusion CT induced acute and delayed order-dependent immune cell count alterations in highly trained youth male judo athletes. In general, power-endurance induced higher acute and delayed immunological stress responses compared to endurance-power. CMJ-force and RPE fluctuated during both CT sessions but went back to baseline 6 h post-exercise.

Clinical Concerns on Sex Steroids Variability in Cisgender and Transgender Women Athletes

Article

Full-text available

Sep 2022

In the female athletic community, there are several endogenous and exogenous variables that influence the status of the hypothalamus-pituitary-ovarian axis and serum sex steroid hormones concentrations (e. g., 17β-estradiol, progesterone, androgens) and their effects. Moreover, female athletes with different sex chromosome abnormalities exist (e. g., 46XX, 46XY, and mosaicism). Due to the high variability of sex steroid hormones serum concentrations and responsiveness, female athletes may have different intra- and inter-individual biological and functional characteristics, health conditions, and sports-related health risks that can influence sports performance and eligibility. Consequently, biological, functional, and/or sex steroid differences may exist in the same and in between 46XX female athletes (e. g., ovarian rhythms, treated or untreated hypogonadism and hyperandrogenism), between 46XX and 46XY female athletes (e. g., treated or untreated hyperandrogenism/disorders of sexual differentiation), and between transgender women and eugonadal cisgender athletes. From a healthcare perspective, dedicated physicians need awareness, knowledge, and an understanding of sex steroid hormones’ variability and related health concerns in female athletes to support physiologically healthy, safe, fair, and inclusive sports participation. In this narrative overview, we focus on the main clinical relationships between hypothalamus-pituitary-ovarian axis function, endogenous sex steroids and health status, health risks, and sports performance in the heterogeneous female athletic community.

Sucesos atléticos: deporte, género y cuerpos mentalizados

Article

Full-text available

Sep 2022

Lucia Ciccia

En este artículo me propongo profundizar, desde los Estudios de Género, en la relación mente-cuerpo en aquellos ámbitos donde la segregación por sexo suele justificarse de acuerdo con la idea extendida acerca de que una genitalidad explica la distribución binaria de ciertos estados psicológicos y comportamientos. En esta ocasión, me ocupo de la actual regulación olímpica y su legitimación respecto del vínculo causal entre testosterona y habilidad atlética. Incorporaré la idea de sucesos y la de cuerpos mentalizados para reinterpretar dicho vínculo en el marco de las normativas de género.

Successful Young Athletes Have Low Probability of Being Ranked Among the Best Senior Athletes, but This Is Higher When Compared to Their Less Successful Peers

Article

Full-text available

Jun 2022

Background Contemporary research has shown that only a small proportion of high achieving young athletes continue to become successful senior athletes. However, there is a lack of empirical literature tracking the success of senior male and female athletes who were considered high achieving as a youth. Hypothesis Athletes of both sexes who are successful in youth categories (U18 and U20) are more likely to be successful senior athletes. Conclusion Data from 67,600 athletes were collated from the tilastopaja.org platform. The inclusion criteria for both genders were determined by top-100 ranking in the U18 and U20 age groups and progression to the top-100 as a senior athlete. Only 23.5% of successful track and field athletes (ranked in top-100) at U18 became a successful senior athlete, while 35.4% were from the U20 group. Girls ranked in the top-100 U18 and U20 categories are significantly more likely to be ranked in the top-100 as a senior when compared to boys. Although, being ranked in the top-50 at U18 and U20 significantly increases the probability of becoming a successful senior athlete when compared with less successful athletes at these age groups ( p < 0.001). Notably, the majority (68.5%) of the most successful senior athletes were not ranked in the top-100 when in the U18 or U20 age groups. Only a small group of track and field athletes that are successful at U18 and U20 become successful at senior level. The most successful track and field youth athletes are significantly more likely to succeed as a senior athlete than their less successful peers, while girls are more likely to be successful than boys.

Analysis of the associations between Salivary cortisol-, alpha-amylase-, and testosterone-responsiveness with the physical contact nature of team handball: a preliminary analysis

Article

Full-text available

Jan 2023
J SPORT MED PHYS FIT

Background: This study evaluated endocrine responsiveness (ER) to physical stress (contact vs. non-contact nature of play) during team handball matches, according to the playing positions, thereby contextualizing the contact nature of the handball match. Methods: The participants were ten male team handball players (24.1 ± 3.17 years, 188.2 ± 6.42 cm, 94.6 ± 9.6 kg) divided into two groups: contact playing positions (CPP) and non-contact playing positions (NCPP). To evaluate the ER, the salivary cortisol (C), testosterone (T), and alpha-amylase (AA) concentrations were assessed before the game, during the halftime break, and after the match. Moreover, playing time (PT) and the number of contacts (NC) were counted post-match by video analysis. To determine possible differences between PT and the NC in the first and second halves of the match, a paired-sample t-test was used. The differences among ER-measures were calculated by the magnitude-based Cohen's effect size. Possible associations between NC and ER were analysed by comparing CPP and NCPP in C, T, and AA. Results: The CPP group performed significantly more physical contacts, while there was no difference in playing time between the groups. A stronger C response was evidenced in players with a longer playing time. During the game, the C response was directly determined by physical contact, with CPP players showing a stronger C response than NCPP players. Conclusions: This study provided evidence of the importance of contact actions during matches and training sessions, as a parameter of calculating training loads and preparing strategies for recovery and injury prevention. Further studies examining larger samples are warranted.

Effects of training on plasmatic cortisol and testosterone in football female referees

Article

Full-text available

May 2022

There is very little about the impact that sports training has on female football referees. Therefore, we determined the effects of a 40-week physical preparation, including a full football season, on plasma testosterone and cortisol concentrations and physical performance in female football referees. Plasma cortisol and testosterone concentrations were assayed together with fitness tests at the beginning of the training period (T0, in September), after 8 weeks from T0 (T1), at the mid of the season (T2, 24 weeks after T0), and at the end of the season (T3, in June, 40 weeks after T0). Plasma cortisol increased during the first period and up to T2 (from 15.4 ± 4.7 to 28.5 ± 3.9 µg/dl; p < 0.001), and then decreased at the end of the season (T3: 16.0 ± 2.4 µg/dl). Plasma testosterone concentration in T0 was 14.2±0.37 µg/dl and increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) and then decreased in T3 (33.5 ± 2.8 µg/dl). Resting testosterone levels in women were very low (14,2 ± 0.37 µg/dl) (Figure 3c). Testosterone increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) whilst, at the end of the season, its concentration decreased (33.5 ± 2.8 µg/dl) (Figure 3c). Significant improvements were observed in all physical performances during the observed period (ANOVA, p < 0.05). Finally, testosterone and cortisol concentrations significantly (p < 0.0001 for both) correlated with maximal oxygen consumption. In T1, testosterone concentration was also significantly correlated with running speed test (p < 0.001). In conclusion, training induces endocrine changes in order to maintain body homeostasis in women referees. It is important that coaches and sports scientists regularly observe changes in endocrine function induced by training and matches in female referees, because they can help maximize referees' performance and limit cases of overtraining.

Weightlifting for Children and Adolescents: A Narrative Review

Article

Nov 2021

The involvement of youth in the sport of weightlifting and the use of weightlifting methods as part of training for youth sport performance appears to be increasing. Weightlifting for children and adolescents has been criticized in some circles and is a controversial aspect of resistance training for young people. Although injuries can occur during weightlifting and related activities, the incidence and rate of injury appear to be relatively low and severe injury is uncommon. A number of performance, physical, and physiological variables, such as body composition, strength, and power, are improved by weightlifting training in children, adolescents, and young athletes. Manipulating program variables, when appropriate, can have a substantial and profound influence on the psychological, physiological, physical, and performance aspects of weightlifters. An understanding of the sport, scientific training principles, and musculoskeletal growth development is necessary to properly construct a reasonable and appropriate training program. A scientific background aids in providing an evidenced basis and sound rationale in selecting appropriate methods and directing adaptations toward more specific goals and enables the coach to make choices about training and competition that might not otherwise be possible. If weightlifting training and competition are age group appropriate and are properly supervised, the sport can be substantially safe and efficacious.

Métodos para el control psicológico en altitud: frecuencia crítica de fusión ocular y perfil de polaridad

Article

Full-text available

Jan 2021

La dosificación correcta del entrenamiento en condiciones de altitud es una exigencia imprescindible, pues en tales circunstancias se originan modificaciones fisiológicas en el organismo de los atletas y se produce un descenso del consumo de oxígeno y del rendimiento aeróbico. La pertinencia del control psicológico en el deporte de alto rendimiento a partir de métodos directos e indirectos ha sido suficientemente justificada. El objetivo de este estudio consiste en la caracterización del comportamiento de la Frecuencia Crítica de Fusión Ocular (FCFO) y las Dimensiones del Perfil de Polaridad (PDP), antes y después de unidades de entrenamiento en condiciones de altitud, en un grupo de 10 deportistas del equipo de la preselección nacional de atletismo de Cuba. Luego del estudio se comprobó que el puntaje en la dimensión estado físico del PDP posterior a la unidad de entrenamiento, disminuyó significativamente y la FCFO aumentó después de esta. Por su parte, las atletas del sexo femenino presentaron un puntaje inferior en el estado físico del PDP posterior a la unidad de entrenamiento, con respecto al obtenido por los hombres en similar medición.

Strength, Endocrine, and Body Composition Alterations across Four Blocks of Training in an Elite 400 m Sprinter

Article

Full-text available

Mar 2021

The ability to produce force rapidly has the potential to directly influence sprinting performance through changes in stride length and stride frequency. This ability is commonly referred to as the rate of force development (RFD). For this reason, many elite sprinters follow a combined program consisting of resistance training and sprint training. The purpose of this study was to investigate the strength, endocrine and body composition adaptations that occur during distinct phases of a block periodized training cycle in a 400 m Olympic level sprinter. The athlete is an elite level 400 m male sprinter (age 31 years, body mass: 74 kg, years of training: 15 and Personal Best (PB): 45.65 s). This athlete completed four distinct training phases of a block periodized training program (16 weeks) with five testing sessions consisting of testosterone:cortisol (T/C) profiles, body composition, vertical jump, and maximum strength testing. Large fluctuations in T/C were found following high volume training and the taper. Minor changes in body mass were observed with an abrupt decrease following the taper which coincided with a small increase in fat mass percentage. Jump height (5.7%), concentric impulse (9.4%), eccentric impulse (3.4%) and power ratio (18.7%) all increased substantially from T1 to T5. Relative strength increased 6.04% from T1 to T5. Lastly, our results demonstrate the effectiveness of a competitive taper in increasing physiological markers for performance as well as dynamic performance variables. Block periodization training was effective in raising the physical capabilities of an Olympic level 400 m runner which have been shown to directly transfer to sprinting performance.

Relationship between General Jump Types and Spike Jump Performance in Elite Female and Male Volleyball Players

Article

Full-text available

Jan 2021

Full-Text Open Access: https://www.mdpi.com/2076-3417/11/3/1105/htm <<<>>> Abstract: In performance testing, it is well-established that general jump types like squat and countermovement jumps have great reliability, but the relationship with volleyball spike jumps is unclear. The objectives of this study were to analyze the relationship between general and spike jumps and to provide improved models for predicting spike jump height by general jump performance. Thirty female and male elite volleyball players performed general and spike jumps in a randomized order. Two AMTI force plates (2000 Hz) and 13 Vicon MX cameras (250 Hz) captured kinematic and kinetic data. Correlation and stepwise-forward regression analyses were conducted at p < 0.05. Simple regression models with general jump height as the only predictor for spike jumps revealed 0.52 ≤ R2 ≤ 0.76 for all general jumps in both sexes (p < 0.05). Alternative models including rate of force development and impulse improved predictions during squat jumps from R2 = 0.76 to R2 = 0.92 (p < 0.05) in females and from R2 = 0.61 to R2 = 0.71 (p < 0.05) in males, and during countermovement jumps with arm swing from R2 = 0.52 to R2 = 0.78 (p < 0.01) in males. The findings include improved prediction models for spike jump height based on general jump performance. The derived formulas can be applied in general jump testing to improve the assessment of sport-specific spike jump performance.

Consumption on steroids: The effect of testosterone on preferences for conspicuous consumption and the moderating role of intrasexual competition

Article

Jan 2021
J BEHAV DECIS MAKING

In line with recent research suggesting that testosterone may only be related to decisions under specific conditions, we show that testosterone is associated with conspicuous consumption only when intrasexual competition is high. In three studies, we provide empirical evidence that prenatal and circulating testosterone are only related to conspicuous consumption when intrasexual competition is high. These findings are in line with recent literature that posits that testosterone is only related to particular decisions or behavior when status is at stake. In Study 1, we find that masculinized digit ratios (an indicator of high prenatal testosterone exposure) are only related to greater conspicuous consumption preferences for men that score high on an intrasexual competitiveness trait measure. In Study 2, we find that masculin-ized digit ratios are associated with greater conspicuous consumption preferences, but only among men who are primed with an intrasexual competition recall task. Finally, the purpose of Study 3 was to test if similar effects held when measuring circulating testosterone. We show that baseline levels of circulating testosterone are associated with greater conspicuous consumption preferences, but only after men are primed with intrasexual competition. Overall, we identify intrasexual competition as a crucial precondition for relationships between testosterone (prenatal and circulating) and conspicuous consumption to emerge. We argue that men with masculin-ized digit ratios and men with high circulating testosterone may be more likely to choose conspicuous products as a status-signaling strategy in the mating market if they are inherently intrasexually competitive or when they encounter an intrasexually competitive situation.

Digit Ratio (2D:4D) and Physical Performance in Female Olympic Athletes

Article

Full-text available

May 2020

Background: The second to fourth digit ratio (2D:4D ratio) is suggested to be a negative correlate of prenatal testosterone. Little is known about the role of the 2D:4D ratio in relation to serum and urinary androgens for physical performance in female athletes. We aimed to compare the 2D:4D ratio in female Olympic athletes with sedentary controls, and to investigate the 2D:4D ratio in relation to serum and urinary androgens and physical performance in the athletes. Methods: This cross-sectional study included 104 Swedish female Olympic athletes participating in power, endurance and technical sports and 117 sedentary controls. The 2D:4D ratio was calculated using direct digit measurements. Serum androgens and urinary androgen metabolites were analyzed by liquid chromatography-tandem mass spectrometry. The athletes performed standardized physical performance tests and body composition was established by dual-energy X-ray absorptiometry. Results: The 2D:4D ratio was significantly lower in the athletes compared with controls although serum testosterone levels were comparable between groups and within normal reference values. The 2D:4D ratio correlated negatively with urinary levels of testosterone glucuronide and 5α- and 5βAdiol-17G, whereas there were no correlations to serum androgen levels. Furthermore, the 2D:4D ratio correlated negatively with strength tests and positively with 3,000-meter running in the athletes. Conclusion: Female Olympic athletes had a lower 2D:4D ratio, possibly reflecting a higher prenatal androgen exposure, than sedentary controls. Furthermore, the 2D:4D ratio was related to urinary levels of androgen metabolites and physical performance in the athletes but not to serum androgen levels. It is suggested that the 2D:4D ratio could reflect androgen metabolism and may be of importance for sporting success in female athletes.

Female hyperandrogenism and elite sport

Article

Full-text available

Mar 2020

Angelica Lindén Hirschberg

Emerging evidence indicates that testosterone, which can increase muscle mass and strength, stimulate erythropoiesis, and promote competitive behaviour, enhances the physical performance of women. Indeed, levels of testosterone within the normal female range are related to muscle mass and athletic performance in female athletes. Furthermore, among these athletes the prevalence of hyperandrogenic conditions, including both polycystic ovary syndrome and rare Differences/Disorders of Sex Development (DSD), which may greatly increase testosterone production, are elevated. Thus, if the androgen receptors of an individual with XY DSD are functional, her muscle mass will develop like that of a man. These findings have led to the proposal that essential hyperandrogenism is beneficial for athletic performance and plays a role in the choice by women to compete in athletic activities. Moreover, a recent randomized controlled trial demonstrated a significant increase in the lean mass and aerobic performance by young exercising women when their testosterone levels were enhanced moderately. Circulating testosterone is considered the strongest factor to explain the male advantage in sport performance, ranging between 10-20 percent. It appears to be unfair to allow female athletes with endogenous testosterone levels in the male range (i.e., 10-20 times higher than normal) to compete against those with normal female androgen levels. In 2012, this consideration led international organisations to establish eligibility regulations for the female classification in order to ensure fair and meaningful competition, but the regulations are controversial and have been challenged in court.

Effects of moderately increased testosterone concentration on physical performance in young women: A double blind, randomised, placebo controlled study

Article

Full-text available

Oct 2019

Objective To investigate the effects of a moderate increase in serum testosterone on physical performance in young, physically active, healthy women. Methods A double blind, randomised, placebo controlled trial was conducted between May 2017 and June 2018 (ClinicalTrials.gov ID: NCT03210558 ). 48 healthy, physically active women aged 18–35 years were randomised to 10 weeks of treatment with 10 mg of testosterone cream daily or placebo (1:1). All participants completed the study. The primary outcome measure was aerobic performance measured by running time to exhaustion (TTE). Secondary outcomes were anaerobic performance (Wingate test) and muscle strength (squat jump (SJ), counter movement jump (CMJ) and knee extension peak torque). Hormone levels were analysed and body composition assessed by dual energy X-ray absorptiometry. Results Serum levels of testosterone increased from 0.9 (0.4) nmol/L to 4.3 (2.8) nmol/L in the testosterone supplemented group. TTE increased significantly by 21.17 s (8.5%) in the testosterone group compared with the placebo group (mean difference 15.5 s; P=0.045). Wingate average power, which increased by 15.2 W in the testosterone group compared with 3.2 W in the placebo group, was not significantly different between the groups (P=0.084). There were no significant changes in CMJ, SJ and knee extension. Mean change from baseline in total lean mass was 923 g for the testosterone group and 135 g for the placebo group (P=0.040). Mean change in lean mass in the lower limbs was 398 g and 91 g, respectively (P=0.041). Conclusion The study supports a causal effect of testosterone in the increase in aerobic running time as well as lean mass in young, physically active women.

The effect of circadian rhythm on drop jump performance

Article

Full-text available

Sep 2019

Abstract BACKGROUND: The circadian rhythm (CR) is a 24-hour cyclic period that influences a wide array of physiological systems and performance sports. However, its specific effect on drop jump (DJ) scores have not been studied. OBJECTIVE: To investigate the effect of circadian rhythm on DJ performances. METHODS: Thirty-three healthy university students (men, n = 16, age: 23.47±2.9 years; fewomen, n = 17, age: 22.25 ±2.27 years) participated in this study. Subjects were tested twice, over two separate days, once in the morning and once in the evening. Subjects started from a drop height of 20 cm and continued until the height where the reactive strength index (RSI) started to decrease. This height was recorded as the optimal drop height (ODH). Ground contact time (GCT) and jump height were also recorded. RESULTS: The ODH values were similar between testing sessions for both genders (p > 0.05). A significant increase in jump height during the evening session was observed in men (p = 0.005, d = 0.80). The RSI values increased significantly in men (p = 0.006, _2 = 0.77) while GCT was similar in both genders (p > 0.05). CONCLUSION: In men, the optimal time of day for DJ explosive training is the evening. Women may benefit from this type of training both during morning and evening sessions. Keywords: Circadian rhythm, drop jump, reactive strength index, optimal drop height, jump height, ground contact time

Digit ratio (2D:4D): relationship with freestyle swimming performance of adolescent well-trained swimmers

Article

Full-text available

Jun 2019

Purpose: The purpose of this study was to determine whether there was a relationship between the digit ratios and freestyle swimming performance of adolescent well-trained swimmers. Material and Methods: Twenty-two well-trained male swimmers who had at least 3 years of swim training experience were recruited as participants. The participants’ mean age was 14.1±1.5 years, body height was 164.5±11.3 cm, and body mass was 54.4±11.2 kg. Participants’ body height, mass, index finger (2D) and ring finger (4D) lengths were measured and digit ratio (2D:4D) and body mass index of participants was calculated. To determine the swimming performance of participants, the short (50m and 100m) and middle (200m and 400m) distance freestyle time-trial swimming tests were performed on participants. The association between the 2D:4D ratio and the swimming performance were determined by the Pearson correlation coefficient. Results. Our findings indicated that there were strong negative correlations (r > .50) between the mean of BMI and swimming times of adolescent swimmers. ( p > .05 ). However, result of this study revealed no relationship between the digit ratio (2D:4D) and swimming performance in adolescent swimmers. ( p > .05 ). Conclusion. As a result, it may be stated that the 2D:4D ratio of swimmers is not a major parameter in predicting swimming performance for adolescent swimmers.

Preconditioning Strategy in Rugby-7s Players: Beneficial or Detrimental?

Article

Full-text available

Dec 2018

Purpose: Preconditioning strategies are considered as opportunities to optimize performance on competition day. While investigations conducted in rugby players on the effects of a morning preconditioning session already exist, additional work is warranted. The aim of this study was to monitor changes in physical and psychophysiological indicators among international Rugby-7s players following a priming exercise. Methods: In a randomized crossover-design, fourteen under-18 international Rugby-7s players completed, at 8:00am, a preconditioning session consisting of a warm-up followed by small-sided games, accelerations and 2 x 50-m maximal sprints (Experimental) or no pre-loading session (Control). Following a 2-hour break, the players performed a set of six 30-m sprints and a Rugby-7s match. Recovery-stress state and salivary stress-markers levels were assessed before the preloading session (Pre), immediately after (Post-1), before the testing session (Post-2) and after (Post-3). Results: Experimental-Control differences in performance across a repeated sprint test consisting of six 30-m sprints were very likely trivial (+0.2 ±0.7%, 3/97/1%). During the match, the total distance covered and the frequency of decelerations were possibly lower (small) in Experimental compared to Control. Differences observed in the other parameters were unclear or possibly trivial. At Post-2, the perceived recovery-stress state was improved (small difference) in Experimental compared with Control. No difference in salivary cortisol response was observed while the preconditioning session induced a higher stimulation of salivary testosterone and alpha-amylase. Conclusions: The players' ability to repeat sprints and physical activity in match-play did not improve but their psychophysiological state was positively affected after the present pre-conditioning session.

Daily Fluctuations in Hormonal and Performance Markers in Collegiate Weightlifters

Article

Full-text available

Jun 2018

The purpose of this study was to assess relationships between daily fluctuations in hormonal and performance markers in weightlifters. Nine male collegiate weightlifters gave daily pre-practice salivary samples for one week and were tested daily for standing broad jump distance; first jump (BJ1) and best jump (BJB) were recorded. Volume-load was heavy on Monday (47%), light on Tuesday (13%), and medium-heavy on Wednesday (40%). To determine if variables differed by day, RM ANOVAs were used with partial-eta squared effect sizes (η2 p) to calculate meaningful changes. RM ANOVA models suggest daily differences occurred for T (F=4.027, p=.024, η2 p =.402), T/C (F=11.735, p=.019, η2 p =.898), and BJ1 (F=6.229, p=.004, η2 p =.509), but not for C (F=1.623, p=.219, η2 p =.213) nor BJB (F=1.088, p=.379, η2 p =.154). Daily fluctuations in BJ1 shared a moderate inverse relationship with daily fluctuations in C (r = -0.42), whereas BJB revealed no association with hormonal markers. T, T/C, and BJ1 appeared to be meaningfully affected by the previous day’s training stress in collegiate weightlifters, suggesting that BJ1 may be indicative of hormonal status and that a one-day reduction in VL may enhance acute athlete readiness.

Effects of acute psychological stress on athletic performance in elite male swimmers

Article

May 2018
J SPORT MED PHYS FIT

Background: While physical activity has been shown to affect psychological as well as physiological stress responses, less research has explored the effects of acute stress on athletic performance. The current study hence aimed to investigate the effect of an Acute Psychological Stress (APS) provocation on performance and plasma lactate concentration during a following 200m swim race among male elite swimmers. Furthermore, associations between physiological stress responses (salivary cortisol and testosterone), and outcome measures (speed and lactate) were explored. Methods: Twenty-three elite male swimmers participated in an experimental counterbalanced within-group repeated measures design consisting of an APS provocation followed by a 200m race and, on a separate day, a control race without prior stress exposure. Salivary cortisol and testosterone were collected prior to each race. Race time was recorded, and serum lactate were collected immediately following, and five min after completed race. Results: Race speed was significantly slower (1.53 (95% CI: 0.08-2.79) seconds) following the APS provocation than under control conditions. Pre-race cortisol levels were positively associated with lactate response when preceding stress exposure was present (rho =.483 immediately, and rho=.429 five minutes post race, p's<0.05). Under control conditions however, both increased testosterone (rho= -657, p=0.001) and cortisol (rho= -.491, p=0.020) levels were associated with faster race times. Conclusions: The results indicated a negative impact of APS exposure on athletic performance. Further, potential beneficial effects on performance from physiological stress responses (as reflected by salivary cortisol and testosterone) may be diminished during performance following an APS provocation, compared with a regular non-provoked performance situation.

Sex Differences in Athletic Performance: Perspectives on Transgender Athletes

Article

Apr 2023
EXERC SPORT SCI REV

Sex hormone concentrations, particularly testosterone, are primary determinants of sex-based differences in athletic and sports performance, and this relationship may inform fair competition and participation for athletes. This article describes the sex-based dichotomy in testosterone and the implications for sex-based differences in individual sports performance, including factors that relate to athletic performance for transgender individuals, and areas of future investigation.

Association between the dry-land strength & power and the kick start kinetics in elite male and female swimmers

Article

Dec 2022

The aim of this research was to determine the association between dry-land exercises and the start kinetics in elite swimmers. Fourteen swimmers (eight males and six females) included in a national team took part in this study. A fixed smith-machine was used to measure the maximal full squat strength (Smax). The height of squat (SJ) and countermovement (CMJ) jumps were collected with a contact mat. The ground reaction force of the kick starts in the three-dimensional axis (Fz horizontal; Fy, vertical; Fx, lateral) was obtained by an instrumented force plate in the starting block. Overall, the Smax showed a high and significant association with Fz (r = 0.60) and Fy (r = 0.87). Moderate and significant associations were found between Fy and SJ (r = 0.51) and CMJ (r = 0.57). While Smax in males showed high association with Fy (r = 0.77), the Smax for females showed greater association with Fz (r = 0.84). As conclusion, the full back squat seems to be the dry-land exercise with higher association with the kick start kinetics. While in males the full squat defines better the vertical component, for females it defines the horizontal one.

Female Testosterone: Contested Terrain

Article

Jan 2021

World Athletics policy narrowly defines female athletes, creating contested bodies in elite sport. Framed by feminist cultural studies and transfeminism, we discuss the eligibility rules and their real-life impact. Women with naturally elevated endogenous testosterone (hyperandrogenism) are being treated as if they are cheating. That high testosterone in female bodies has been deemed an unfair competitive advantage is consistent with dominant cultural narratives rather than the research about testosterone and sport performance. Applying an intersectional lens, it becomes clear that race, region, class, and nation intersect so that women athletes from the Global South are disproportionately affected by the eligibility regulations. This creation of contested bodies has led to critical mental and physical health outcomes. Cherry-picking one biological component of a body as the cause of exceptional performance in elite sport is irresponsible. Instead, we need education, compassion, and to follow sound science grounded in moral and ethical research.

Female Hyperandrogenism in Elite Sports and the Athletic Triad

Article

Oct 2021
SEMIN REPROD MED

Angelica Lindén Hirschberg

Essential hyperandrogenism seems to be overrepresented in female elite athletes. This applies to mild forms such as polycystic ovary syndrome, as well as rare differences/disorders of sex development (DSD). The reason is likely a selection bias since there is increasing evidence that androgens are beneficial for athletic performance by potent anabolic effects on muscle mass and bone mass, and stimulation of erythropoiesis. XY DSD may cause a greatly increased production of testosterone in the male range, that is, 10 to 20 times higher than the normal female range. The established regulations concerning the eligibility of female athletes with severe hyperandrogenism to compete in the female classification remain controversial. The most common cause of menstrual disorders in female athletes, however, is probably an acquired functional hypothalamic disturbance due to energy deficiency in relation to energy expenditure, which could lead to low bone mineral density and increased risk of injury. This condition is particularly common in endurance and esthetic sports, where a lean body composition is considered an advantage for physical performance. It is important to carefully evaluate endocrine disturbances and menstrual disorders in athletes since the management should be specific according to the underlying cause.

Influence of Female Sex Hormones on Ultra-Running Performance and Post-Race Recovery: Role of Testosterone

Article

Full-text available

Oct 2021
Int J Environ Res Publ Health

In recent years, increasing numbers of women have participated in extremely long races. In adult males, there is a clear association between physiological levels of endogenous sex hormones and physical performance. However, the influence of plasmatic sex hormones and the effects of different types of hormonal contraception (HC) on the modulation of physical performance in adult females remain to be fully clarified. Eighteen female ultra-endurance athletes were recruited to participate in the study. Different variables were studied, including hematological parameters, body mass index, and body composition. Strength measurements were obtained using the squat-jump and hand-grip test. A repeated-measures analysis demonstrated significant differences in hemato-logical values of CK and LDH pre-race as compared to immediately post-race and after 24/48 h. Furthermore, statistical differences were found in squat-jump and hand-grip test results after the ultramarathon. Testosterone, estradiol, and the testosterone/estrogen ratio were significantly correlated with muscle fatigue and were found to be indirect markers of muscle damage. A multivariate analysis demonstrated the protective role of testosterone against muscle damage and severe fatigue. Fluctuations in endogenous testosterone levels were correlated with greater fatigability and muscle damage after the competition. Adjusting the menstrual cycle with HC would not provide any further benefit to the athlete's competitive capacity.

Beach Volleyball: Temporal Analysis and Endocrine Responses of National Athletes

Article

Full-text available

Dec 2020

This study aimed to characterize temporal aspects and verify the acute effect of a beach volleyball game on testosterone, cortisol, and T: C ratio of young athletes. Also, to verify whether the hormonal responses were different between blockers and defenders. Sixteen male athletes of national-level participated (age 17±2.44 years). Each athlete played a game with official rules, being filmed for subsequent analysis. Saliva was used to measure testosterone and cortisol levels and calculate testosterone/cortisol ratio (T: C ratio) using ELISA method. The concentration of these hormones was compared over time (beginning, end of first set, and end of the match) and between functions. Usually, the total match duration was 30min and 49s (± 0.01s), with rallies of 6 seconds (± 01s) and time between rallies of 20 seconds (± 02s). Cortisol showed a linear trend, increasing over time, and T: C ratio showed a quadratic trend, decreasing at the end of the first set and reestablishing at the end of the match. Blockers T: C ratio of pre-post match had a trivial but negative effect (d= −0.198). Approximately 30 minutes of beach volleyball affects the concentration of testosterone, cortisol, and T: C ratio. Besides, blockers seem slightly more physically demanding.

Endocrine Aspects in Performance and Recovery in Basketball

Chapter

Oct 2020

The effectiveness of exercise training depends on the training load and on the individual ability to tolerate it, and an imbalance between the two may lead to under- or overtraining. Therefore, efforts have been made to find objective parameters to quantify the balance between training load and the athlete’s tolerance. One of the unique features of exercise is that it leads to a simultaneous increase in antagonistic circulating mediators. On the one hand, exercise stimulates anabolic components such as testosterone, growth hormone (GH), and IGF-I (insulin-like growth factor-I). On the other hand, exercise elevates catabolic hormones like cortisol and pro-inflammatory cytokines such as interleukin-6 (IL-6). The very fine balance between the anabolic and inflammatory/catabolic response to exercise will determine the effectiveness of training and the health consequences of exercise. In this chapter, we review the changes in the anabolic–catabolic hormonal balance and circulating inflammatory cytokines both in single exercise bouts, following prolonged training, and in relation to a competitive match, and we demonstrate how these changes may be used by athletes and their coaching staff to gauge the training intensity focusing on basketball.

Is testosterone responsible for athletic success in female athletes?

Article

Full-text available

Jun 2020

BACKGROUND: The aim of this study was to determine the interrelationship between the resting serum testosterone (T) levels of female athletes from different types of sporting events and their athletic success. METHODS: The study involved 599 Russian international-level female athletes (95 highly elite, 190 elite, and 314 sub-elite; age: 16-35 years) and 298 age-matched female controls. The athlete cohort was stratified into four groups according to event duration, distance, and type of activity: 1) endurance athletes, 2) athletes with mixed activity, 3) speed/strength athletes, and 4) sprinters. Athletic success was measured by determining the level of achievement of each athlete. RESULTS: The mean (SD) T levels of athletes and controls were 1.65 (0.87) and 1.76 (0.6) nmol/L (P=0.057 for difference between groups) with ranges of 0.08-5.82 and 0.38-2.83 nmol/L in athletes and controls, respectively. T levels were positively associated with athletic success in sprinters (P=0.0002 adjusted for age) only. Moreover, none of the sub-elite sprinters had T>1.9 nmol/L, while 50% of elite and highly elite sprinters had T>1.9 nmol/L (OR=47.0; P<0.0001). CONCLUSIONS: Our data suggest that the measurement of the serum T levels significantly correlates with athletic success in sprinters but not other types of athletes and in the future may be useful in the prediction of sprinting ability.

The Role of Androgens for Body Composition and Physical Performance in Women

Chapter

Jul 2019

Angelica Lindén Hirschberg

Androgens are considered beneficial for athletic performance by potent anabolic effects on muscle mass and bone tissue. Testosterone also increases the formation of new blood cells and circulating hemoglobin, which will enhance oxygen uptake. Furthermore, androgens may exert behavioral and psychological effects of importance for athletic performance including increased mental drive and competitiveness. Studies in men have shown dose–dependent relationship between circulating testosterone with muscle mass and strength, as well as circulating hemoglobin. Experimental evidence in women is much more limited. However, recent studies in nonathletic and athletic women have demonstrated associations between endogenous testosterone levels, muscle mass, and muscle strength. Furthermore, it has been demonstrated that women with mild hyperandrogenism like polycystic ovary syndrome (PCOS) are overrepresented in elite athletes. PCOS, which has a genetic component, is associated with an anabolic body composition, and this syndrome may therefore confer an advantage for physical performance and could play a role in the recruitment of women to competitive sport activities. The prevalence of severe hyperandrogenism, such as disorders of sex development (DSD), is also increased among female athletes. DSD may cause a greatly increased production of testosterone in the male range. These results support a significant role of endogenous androgens for athletic performance in women.

Performance-based correlates to vertical jump height and power values in women

Article

Dec 2018

BACKGROUND AND OBJECTIVE: Stark inter-gender differences in vertical jump performance exist. Performance-based correlates to the vertical jump are not well understood in women. METHODS: Women (n= 129) did countermovement vertical jumps as their data were collected concurrently by a Vertec and force plate; the latter provided performance-based correlates to their jumps. Multivariate regression examined the ability of the performance-based variable to serve as correlates of vertical jump height and power variances. RESULTS: Performance-based variables predicted moderate (r2= 0.28) and large (r2= 0.74) amounts of vertical jump height and power variance respectively. Per criterion measure, peak force did not have the highest univariate correlation. CONCLUSIONS: Peak force, typically the strongest correlate to vertical jump performance in men, was not as strong a predictor of the variance in women. Instead women rely on a variety of kinetic and temporal variables to maximize their vertical jump height and power values.

Endocrinological Aspects in Handball

Chapter

May 2018

The effectiveness of physical training depends on the training load and on the individual ability to tolerate it, and an imbalance between the two may lead to under- or overtraining. Therefore, many efforts have been made to find objective parameters to quantify the balance between training load and the athlete’s tolerance.

Mechanical behaviour of leg extensor muscles in male and female sprinters

Article

Full-text available

Jan 2002

Leg extensor muscle characteristics, running speed and serum testosterone were studied in sixteen males and twelve female sprinters. The rise of center of gravity was measured during squat jumps executed without (SJ) and with extra loads (SJbm), counter movement jump (CMJ) and continuous jumping (CJ) for 5 s. Nine females and nine males performed also half-squat exercises with extra loads ranging from 50% to 200% of the subject's body mass (bm). Average mechanical power (P), force (F) and velocity (v) were calculated and measured during half-squat exercises using the Ergopower®. Total serum testosterone (TT) was determined in venous blood. In women, 60 m dash, SJ, CMJ and CJ performances were significantly lower (P<0.001) than men. Gender differences were not found in F during half-squat exercises and in SJbm. Women demonstrated significantly higher ratios CMJ:SJ and CJ:SJ than men. With loads 50-100 % of bm men demonstrated greater v and P than women. It was suggested that high testosterone level in men might be a factor ensured superiority in explosive power and speed, but not in muscle strength adjusted to body mass.

Physiological responses to resistance-exercise in athletes self-administering anabolic steroids

Article

Full-text available

Jan 1991

Endocrine and metabolic responses to resistance exercise were compared in 5 athletes self-administering (SL) anabolic steroids and 8 athletes (L) not using these compounds. Exercise consisted of 5 sets of 10 repetitions in the squat and quarter squat. Blood samples were collected before (pre) and immediately after (post) exercise, and following 30 minutes of recovery (post-30). Except for significantly lower lactate concentrations in SL (p less than 0.015) at post-30, the responses to exercise and recovery were similar in both groups. Significantly higher hematocrits (p less than 0.0001), total androgen concentrations (p less than 0.0001), and androgen/cortisol ratios (p less than 0.0001) were observed in the SL group across all time periods. Plasma androgen concentrations increased about 22% in SL following exercise, even though plasma LH concentrations were significantly lower (p less than 0.0001) than in L. Plasma ACTH and cortisol concentrations were not significantly affected. Both groups displayed similar endocrine and metabolic responses to an acute bout of resistance exercise. The higher androgen/cortisol ratios and lower plasma lactate concentrations during recovery are two potential factors which may help explain the lower subjective level of fatigue following training sessions often reported by individuals who use anabolic steroids.

Testosterone-induced changes in contractile protein isoforms in the sexually dimorphic temporalis muscle of the guinea pig

Article

Full-text available

Nov 1986

The guinea pig temporalis muscle is sexually dimorphic, classified histochemically as a fast-red muscle in the female, but as a fast-white muscle in the adult male. Since this sexual difference in metabolic properties is related to plasma testosterone levels, we asked if testosterone also affected the contractile protein isoforms. In the newborn guinea pig, both male and female temporalis muscles contained a fast-red isoform of the myosin heavy chain and approximately equal amounts of alpha- and beta-tropomyosins. At puberty, the male began to replace the fast-red isoform with a fast-white isoform of the heavy chain and by 120 days the muscle contained predominantly the fast-white myosin heavy chain. This transition in myosins in the male was accompanied by a shift to greater than 90% alpha-tropomyosin. No changes in myosins or tropomyosins were observed in the female. The changes in the male could be reversed by castration and could be mimicked in the female by the injection of testosterone. Although these same myosins and tropomyosins could be detected in other fast-twitch muscles, postpartum transitions in contractile protein isoforms in those muscles were testosterone-insensitive, and no sexual dimorphism of these proteins was seen in other muscles.

The Effects of Supraphysiologic Doses of Testosterone on Muscle Size and Strength in Normal Men

Article

Full-text available

Aug 1996

Athletes often take androgenic steroids in an attempt to increase their strength. The efficacy of these substances for this purpose is unsubstantiated, however. We randomly assigned 43 normal men to one of four groups: placebo with no exercise; testosterone with no exercise; placebo plus exercise; and testosterone plus exercise. The men received injections of 600 mg of testosterone enanthate or placebo weekly for 10 weeks. The men in the exercise groups performed standardized weight-lifting exercises three times weekly. Before and after the treatment period, fat-free mass was determined by underwater weighing, muscle size was measured by magnetic resonance imaging, and the strength of the arms and legs was assessed by bench-press and squatting exercises, respectively. Among the men in the no-exercise groups, those given testosterone had greater increases than those given placebo in muscle size in their arms (mean [+/-SE] change in triceps area, 424 +/- 104 vs. -81 +/- 109 square millimeters; P < 0.05) and legs (change in quadriceps area, 607 +/- 123 vs. -131 +/- 111 square millimeters; P < 0.05) and greater increases in strength in the bench-press (9 +/- 4 vs. -1 +/- 1 kg, P < 0.05) and squatting exercises (16 +/- 4 vs. 3 +/- 1 kg, P < 0.05). The men assigned to testosterone and exercise had greater increases in fat-free mass (6.1 +/- 0.6 kg) and muscle size (triceps area, 501 +/- 104 square millimeters; quadriceps area, 1174 +/- 91 square millimeters) than those assigned to either no-exercise group, and greater increases in muscle strength (bench-press strength, 22 +/- 2 kg; squatting-exercise capacity, 38 +/- 4 kg) than either no-exercise group. Neither mood nor behavior was altered in any group. Supraphysiologic doses of testosterone, especially when combined with strength training, increase fat-free mass and muscle size and strength in normal men.

Hormonal Responses in Strenuous Jumping Effort.

Article

Full-text available

Feb 1996

In order to test the possibility for rapid responses of blood hormone levels in short-term supramaximal exercises, serum concentrations of corticotropin (ACTH), cortisol (C), total testosterone (tT), free testosterone (fT), growth hormone (GH), thyrotropin (TSH), free thyroxine (fT4), free triiodothyronine (fT3), prolactin (PRL), insulin-like growth factor (IGF-I), and sex hormone-binding globulin (SHBG) were determined by RIA procedures in blood samples obtained before and immediately after a 60-s period of consecutive vertical jumps (Bosco test). The study subjects were 16 Italian professional soccer players. Immediately after exercise, significant increases (p < 0.05) were found in the concentrations of ACTH (by 39%), C (by 14%), TSH (by 20%), fT3 (by 28%), fT4 (by 30%), tT (by 12%), fT (by 13%), and SHBG (by 21%). Significant changes were not detected in the blood levels of GH, IGF-I and PRL. Most pronounced testosterone responses were typical for persons of high jumping performance (the increase of serum tT correlated with average power output, r = 0.61 and jumping height, r = 0.66). The larger the drop in power output during 60-s jumping, the higher was the thyroid response: the difference in jumping height between the first and last 15-s period correlated with increases in TSH (r = 0.52) and in fT4, (r = 0.55). In conclusion, the obtained results indicate that in intense exercise, causing the rapid development of fatigue, rapid increases in serum levels of hormones of the pituitary-adrenocortical, pituitary-gonadal and pituitary-thyroid systems occur.

Anabolic-androgenic steroid induced alterations in choline acetyltransferase messenger RNA levels of spinal cord motoneurons in the male rat

Article

Full-text available

Jul 1997
NEUROSCIENCE

The effect of chronic supraphysiological doses of anabolic-androgenic steroids, such as those illegally used by recreational, amateur and professional athletes to increase muscle mass and strength, on motoneurons has not been established. The choline acetyltransferase activity levels of perineal muscles in the male rat are modulated by plasma testosterone levels. These muscles are innervated by the sexually dimorphic motoneurons of the spinal nucleus of the bulbocavernosus. Since the primary source of choline acetyltransferase in muscle is motoneuronal, testosterone may modulate perineal muscle choline acetyltransferase activity by regulating choline acetyltransferase messenger RNA levels in motoneurons. The purpose of this study was to determine if choline acetyltransferase messenger RNA levels in cervical and lumbar spinal motoneurons are affected by chronic (four weeks) changes of plasma testosterone levels in the adult male rat. Using in situ hybridization, choline acetyltransferase messenger RNA levels were analysed in four motor columns: the spinal nucleus of the bulbocavernosus, the retrodorsal lateral nucleus of the lumbar spinal cord, and the lumbar lateral motor columns of the cervical and lumbar spinal cords. Chronic exposure to supraphysiological levels of testosterone (five- to ten-times physiologic levels) significantly increased choline acetyltransferase messenger RNA in all four motor columns. Subsequent to castration, choline acetyltransferase messenger RNA levels decreased in motoneurons of the spinal nucleus of the bulbocavernosus and the retrodorsal lateral nucleus. This observation suggests that the decrease in choline acetyltransferase activity levels of muscles innervated by spinal nucleus of the bulbocavernosus motoneurons may be due to changes in choline acetyltransferase protein levels. Indeed, testosterone replacement therapy of castrated males prevented the decline of choline acetyltransferase messenger RNA levels in motoneurons.

Psychosexual effects of menopause: Role of androgens

Article

Full-text available

Apr 1999
AM J OBSTET GYNECOL

Philip M Sarrel

Ovarian hormones-estrogens, androgens, and progesterone-produce a myriad of effects in the nervous system. The effects of androgens in the brain are mediated through androgen-specific receptors and by the aromatization of testosterone to estradiol. Alterations in the circulating levels of androgens play an important role in psychologic and sexual changes that occur after menopause. The effects of short-term estrogen therapy in improving psychologic symptoms, maintaining vaginal lubrication, decreasing vaginal atrophy, and increasing pelvic blood flow in postmenopausal women are well documented. However, some patients require more than estrogen alone to improve psychologic dysfunction, decreased sexual desire, or other sexual problems associated with menopause. Results from clinical studies show that hormone replacement therapy with estrogen plus androgens provides greater improvement in psychologic (eg, lack of concentration, depression, and fatigue) and sexual (eg, decreased libido and inability to have an orgasm) symptoms than does estrogen alone in naturally and surgically menopausal women.

Short-Term Oxandrolone Administration Stimulates Net Muscle Protein Synthesis in Young Men 1

Article

Full-text available

Sep 1999

Short term administration of testosterone stimulates net protein synthesis in healthy men. We investigated whether oxandrolone [Oxandrin (OX)], a synthetic analog of testosterone, would improve net muscle protein synthesis and transport of amino acids across the leg. Six healthy men [22+/-1 (+/-SE) yr] were studied in the postabsorptive state before and after 5 days of oral OX (15 mg/day). Muscle protein synthesis and breakdown were determined by a three-compartment model using stable isotopic data obtained from femoral arterio-venous sampling and muscle biopsy. The precursor-product method was used to determine muscle protein fractional synthetic rates. Fractional breakdown rates were also directly calculated. Total messenger ribonucleic acid (mRNA) concentrations of skeletal muscle insulin-like growth factor I and androgen receptor (AR) were determined using RT-PCR. Model-derived muscle protein synthesis increased from 53.5+/-3 to 68.3+/-5 (mean+/-SE) nmol/min.100 mL/leg (P < 0.05), whereas protein breakdown was unchanged. Inward transport of amino acids remained unchanged with OX, whereas outward transport decreased (P < 0.05). The fractional synthetic rate increased 44% (P < 0.05) after OX administration, with no change in fractional breakdown rate. Therefore, the net balance between synthesis and breakdown became more positive with both methodologies (P < 0.05) and was not different from zero. Further, RT-PCR showed that OX administration significantly increased mRNA concentrations of skeletal muscle AR without changing insulin-like growth factor I mRNA concentrations. We conclude that short term OX administration stimulated an increase in skeletal muscle protein synthesis and improved intracellular reutilization of amino acids. The mechanism for this stimulation may be related to an OX-induced increase in AR expression in skeletal muscle.

Proof of the effect of testosterone on skeletal muscle

Article

Full-text available

Aug 2001

In spite of the widespread abuse of androgenic steroids by athletes and recreational body-builders, the effects of these agents on athletic performance and physical function remain poorly understood. Experimentally induced androgen deficiency is associated with a loss of fat-free mass; conversely, physiologic testosterone replacement of healthy, androgen-deficient men increases fat-free mass and muscle protein synthesis. Testosterone supplementation of HIV-infected men with low testosterone levels and of older men with normally low testosterone concentrations also increases muscle mass. However, we do not know whether physiologic testosterone replacement can improve physical function and health-related quality of life, and reduce the risk of falls and disability in older men or those with chronic illness. Testosterone increases maximal voluntary strength in a dose-dependent manner and thus might improve performance in power-lifting events. However, testosterone has not been shown to improve performance in endurance events. The mechanisms by which testosterone increases muscle mass are not known, but probably involve alterations in the expression of multiple muscle growth regulators.

Testosterone-induced increase in muscle size in healthy young men is associated with muscle fiber hypertrophy

Article

Full-text available

Jul 2002

Administration of replacement doses of testosterone to healthy hypogonadal men and supraphysiological doses to eugonadal men increases muscle size. To determine whether testosterone-induced increase in muscle size is due to muscle fiber hypertrophy, 61 healthy men, 18-35 yr of age, received monthly injections of a long-acting gonadotropin-releasing hormone (GnRH) agonist to suppress endogenous testosterone secretion and weekly injections of 25, 50, 125, 300, or 600 mg testosterone enanthate (TE) for 20 wk. Thigh muscle volume was measured by magnetic resonance imaging (MRI) scan, and muscle biopsies were obtained from vastus lateralis muscle in 39 men before and after 20 wk of combined treatment with GnRH agonist and testosterone. Administration of GnRH agonist plus TE resulted in mean nadir testosterone concentrations of 234, 289, 695, 1,344, and 2,435 ng/dl at the 25-, 50-, 125-, 300-, and 600-mg doses, respectively. Graded doses of testosterone administration were associated with testosterone dose and concentration-dependent increase in muscle volume measured by MRI (changes in vastus lateralis volume, -4, +7, +15, +32, and +48 ml at 25-, 50-, 125-, 300-, and 600-mg doses, respectively). Changes in cross-sectional areas of both type I and II fibers were dependent on testosterone dose and significantly correlated with total (r = 0.35, and 0.44, P < 0.0001 for type I and II fibers, respectively) and free (r = 0.34 and 0.35, P < 0.005) testosterone concentrations during treatment. The men receiving 300 and 600 mg of TE weekly experienced significant increases from baseline in areas of type I (baseline vs. 20 wk, 3,176 +/- 186 vs. 4,201 +/- 252 microm(2), P < 0.05 at 300-mg dose, and 3,347 +/- 253 vs. 4,984 +/- 374 microm(2), P = 0.006 at 600-mg dose) muscle fibers; the men in the 600-mg group also had significant increments in cross-sectional area of type II (4,060 +/- 401 vs. 5,526 +/- 544 microm(2), P = 0.03) fibers. The relative proportions of type I and type II fibers did not change significantly after treatment in any group. The myonuclear number per fiber increased significantly in men receiving the 300- and 600-mg doses of TE and was significantly correlated with testosterone concentration and muscle fiber cross-sectional area. In conclusion, the increases in muscle volume in healthy eugonadal men treated with graded doses of testosterone are associated with concentration-dependent increases in cross-sectional areas of both type I and type II muscle fibers and myonuclear number. We conclude that the testosterone induced increase in muscle volume is due to muscle fiber hypertrophy.

Reliability and Factorial Validity of Squat and Countermovement Jump Tests

Article

Aug 2004

The primary aim of this study was to determine reliability and factorial validity of squat (SJ) and countermovement jump (CMJ) tests. The secondary aim was to compare 3 popular methods for the estimation of vertical jumping height. Physical education students (n = 93) performed 7 explosive power tests: 5 different vertical jumps (Sargent jump, Abalakow's jump with arm swing and without arm swing, SJ, and CMJ) and 2 horizontal jumps (standing long jump and standing triple jump). The greatest reliability among all jumping tests (Cronbach's alpha = 0.97 and 0.98) had SJ and CMJ. The reliability alpha coefficients for other jumps were also high and varied between 0.93 and 0.96. Within-subject variation (CV) in jumping tests ranged between 2.4 and 4.6%, the values being lowest in both horizontal jumps and CMJ. Factor analysis resulted in the extraction of only 1 significant principal component, which explained 66.43% of the variance of all 7 jumping tests. Since all jumping tests had high correlation coefficients with the principal component (r = 0.76-0.87), it was interpreted as the explosive power factor. The CMJ test showed the highest relationship with the explosive power factor (r = 0.87), that is, the greatest factorial validity. Other jumping tests had lower but relatively homogeneous correlation with the explosive power factor extracted. Based on the results of this study, it can be concluded that CMJ and SJ, measured by means of contact mat and digital timer, are the most reliable and valid field tests for the estimation of explosive power of the lower limbs in physically active men.

Short-Term Oxandrolone Administration Stimulates Net Muscle Protein Synthesis in Young Men

Article

Aug 1999

Melinda Sheffield-Moore

Proof of the effect of testosterone on skeletal muscle

Article

Jul 2001

Shalender Bhasin

Sexual dimorphism and androgen effect on spinal motoneurons innervating the rat flexor digitorum brevis

Article

Nov 1991
BRAIN RES

The foot muscle, flexor digitorum brevis, is innervated by motoneurons in the retrodorsolateral nucleus of the lumbar spinal cord in rats. We found this muscle to be sexually dimorphic, but insensitive to the anabolic or catabolic effects of androgen manipulation in adulthood: the flexor digitorum brevis was larger in adult male rats than in females, with no decrease in mass after castration in males nor any increase in size after androgen treatment of ovariectomized females. The cross-sectional area of motoneurons innervating this muscle was also sexually dimorphic, i.e., the motoneurons were larger in males. In contrast to the absence of an androgen effect on target muscle size, however, cross-sectional area of motoneurons decreased in adult males as a result of castration, and increased in adult females after androgen treatment. The dissociation of androgen effects on muscle mass and motoneuron size suggests possibility of steroid effects upon motoneurons independent of effects upon target musculature.

The Relationship Between Testosterone and Aggression: A Meta-Analysis

Article

Nov 2001
AGGRESS VIOLENT BEH

In non-human animals, the relationship between testosterone and aggression is well established. In humans, the relationship is more controversial. To clarify the relationship, Archer conducted three meta-analyses and found a weak, positive relationship between testosterone and aggression. Unfortunately, each of the analyses included only five to six studies. The aim of the present study was to re-examine the relationship between testosterone and aggression with a larger sample of studies. The present analyses are based on 45 independent studies (N=9760) with 54 independent effect sizes. Only studies that reported a p-value or effect size were included in the analyses and the sample may underestimate the proportion of non-significant findings in the population. Correlations ranged from −0.28 to 0.71. The mean weighted correlation (r=0.14) corroborates Archer's finding of a weak positive relationship.

Sex difference in strength

Article

Jul 1979
AM J SPORT MED

Sequence of Changes in Body Composition Induced by Testosterone and Reversal of Changes After Drug Is Stopped

Article

Feb 1992

--To study the changes in body composition produced by large doses of testosterone and reversal of changes when the drug is discontinued. --Weekly injections of testosterone enanthate were given to young adult male volunteers for 12 weeks. Repeated assays of lean body mass (LBM) by potassium 40 counting were made during this period and at intervals during the ensuing 5 to 6 months. --Subjects who were living on their own, who were known to be free of significant disease, and who volunteered as controls for a study of patients with neuromuscular disease. Assays were done in the Clinical Research Center. --Changes in body weight, LBM, and (by subtraction) body fat. --Testosterone treatment produced a progressive increase in LBM and a progressive decrease in body fat. Body composition reverted slowly toward normal when the injections were stopped; thus, the effects of testosterone lingered for some time. The magnitude of the observed changes in LBM was in keeping with the change in urinary creatinine excretion reported for these same subjects. --Testosterone is a powerful anabolic agent that also serves to reduce body fat content.

Effect of testosterone on muscle and muscle protein synthesis

Article

Feb 1989

We have studied the effect of a pharmacological dose of testosterone enanthate (3 mg.kg-1.wk-1 for 12 wk) on muscle mass and total-body potassium and on whole-body and muscle protein synthesis in normal male subjects. Muscle mass estimated by creatinine excretion increased in all nine subjects (20% mean increase, P less than 0.02); total body potassium mass estimated by 40K counting increased in all subjects (12% mean increase, P less than 0.0001). In four subjects, a primed continuous infusion protocol with L-[1-13C]leucine was used to determine whole-body leucine flux and oxidation. Whole-body protein synthesis was estimated from nonoxidative flux. Muscle protein synthesis rate was determined by measuring [13C]leucine incorporation into muscle samples obtained by needle biopsy. Testosterone increased muscle protein synthesis in all subjects (27% mean increase, P less than 0.05). Leucine oxidation decreased slightly (17% mean decrease, P less than 0.01), but whole-body protein synthesis did not change significantly. Muscle morphometry showed no significant increase in muscle fiber diameter. These studies suggest that testosterone increases muscle mass by increasing muscle protein synthesis.

Plasma Testosterone, Dominance Rank and Aggressive Behaviour in Male Rhesus Monkeys

Article

Jul 1971

An animal's plasma testosterone is related to its dominance rank and the frequency of aggressive behaviour exhibited in a social group.

Testosterone increases acetylcholine receptor number in the ?levator ani? muscle of the rat

Article

Mar 1982

The "levator ani" muscle of male rats provides a neuromuscular system in which both the muscle and its motoneurons have high levels of androgen receptors. Two weeks of castration caused a 48% loss of acetylcholine receptors in this muscle. One week of testosterone propionate injections initiated on week after castration increased receptor number by 27% over untreated castrate levels. These changes paralleled changes in muscle protein content. In contrast, castration and testosterone treatments of castrates had no effect on total. Triton X-100-extractable acetylcholinesterase activity. This system may provide a useful model of synaptic plasticity.

Electromechanical behaviour of human muscles in vertical jumps

Article

Feb 1982
Eur J Appl Physiol Occup Physiol

The relationships of muscle structure to the potentiation of myoelectrical activity and to the use of prestretching in five lower limb muscles were studied in different vertical jumping conditions. The subjects for the study were six male students, divided according to the muscle fiber distribution in m. vastus lateralis into "fast" and "slow" groups. The subjects performed vertical jumps (1) from a static squatting position (DJ) from five different heights. Myoelectrical (EMG) activity was recorded from mm. gluteus maximus, vastus lateralis, vastus medialis, rectus femoris and gastrocnemius in each jumping condition and integrated (IEMG) for the eccentric and concentric phases of contact. EMG activity showed potentiation during the eccentric phase of movement when compared to the concentric phase. The "fast" and "slow" groups did not differ significantly in this respect, whereas in DJ conditions the relative (% from SJ) height of rise of the center of gravity was greater in the "slow" than in the "fast" group. The result indicated that the utilization of elastic energy during jumping was possible better in subjects having a high percentage of slow twitch muscle fibres in their vastus lateralis muscles.

The Anabolic Action of Testosterone

Article

Aug 1996

C. Wayne Bardin

The paper by Bhasin et al.1 in this issue of the Journal shows that a dose of testosterone enanthate (600 mg weekly for 10 weeks) that produces supraphysiologic serum concentrations of testosterone in men increases muscle size and strength and that the effects of exercise are additive to those of testosterone. Even though athletes have suggested for years that androgens increase muscle mass, there are two main reasons why it has taken until 1996 for this fact to be demonstrated in a clinical trial. First, most earlier studies did not control for the independent effects of testosterone and exercise. Bhasin . . .

Relationships between field fitness test and basal serum testosterone and Cortisol levels in soccer players

Article

Jun 1996

The aim of this study was to investigate the existence of a relationship between performance capacities and blood levels of testosterone (T) and cortisol (C). Thirty-two professional soccer players volunteered for the study. Morning levels of hormones were plotted against results of maximal vertical jump with a preparatory counter-movement (CMJ), 30 m running, and Cooper's 12-min running test. The serum T was positively related to both CMJ and average running speed (r=0.43 and r=0.47, respectively). Serum levels of C and T were in negative correlation (r= -0.40 and r= -0.49, respectively) with the results of Cooper's test. It was concluded that athletes with better explosive strength and sprint running performances have a higher basal level of testosterone. The results suggest a relationship between testosterone production and development of fast twitch muscle fibres in athletes.

Testosterone injection stimulates net protein synthesis but not tissue amino acid transport

Article

Dec 1998
Am J Physiol

Testosterone administration (T) increases lean body mass and muscle protein synthesis. We investigated the effects of short-term T on leg muscle protein kinetics and transport of selected amino acids by use of a model based on arteriovenous sampling and muscle biopsy. Fractional synthesis (FSR) and breakdown (FBR) rates of skeletal muscle protein were also directly calculated. Seven healthy men were studied before and 5 days after intramuscular injection of 200 mg of testosterone enanthate. Protein synthesis increased twofold after injection (P < 0.05), whereas protein breakdown was unchanged. FSR and FBR calculations were in accordance, because FSR increased twofold (P < 0.05) without a concomitant change in FBR. Net balance between synthesis and breakdown became more positive with both methodologies (P < 0.05) and was not different from zero. T injection increased arteriovenous essential and nonessential nitrogen balance across the leg (P < 0.05) in the fasted state, without increasing amino acid transport. Thus T administration leads to an increased net protein synthesis and reutilization of intracellular amino acids in skeletal muscle.

Androgens and Mood Dysfunction in Women: Comparison of Women With Polycystic Ovarian Syndrome to Healthy Controls

Article

May 2004
PSYCHOSOM MED

Our understanding of the organizational and activational effects of human gonadal hormones on behavior has depended on the study of endocrine disorders. Polycystic ovarian syndrome (PCOS) is a hormonal disorder that begins in puberty and is characterized by chronically augmented free testosterone (FT) levels. The purposes of this study were 1) to compare negative mood states of women with PCOS to those of women with normal hormonal levels and 2) to examine the relationship between negative moods and androgens. Twenty-seven women with PCOS were case-matched to 27 normal menstruating women on body mass index since being overweight is a common symptom of PCOS and could affect mood states. Serum levels of FT, total testosterone, sex hormone binding globulin, estradiol, and progesterone were determined. Self-reported depression, anger, anxiety, and aggression were analyzed between groups, and individual scores were compared across groups to hormone values. Depression was significantly increased in the PCOS group and remained so after considering the variance related to physical symptomatology and other mood states. Furthermore, a curvilinear relationship between FT and negative affect across groups was suggested: the most elevated negative mood-scale scores were associated with FT values just beyond the upper limits of normal, while lower negative mood levels corresponded to both normal and extremely high values of FT. These results are consistent with a model of activational influences of testosterone on adult female behavior. Implications are discussed for future research and for treatment of PCOS and other menstrual-cycle mood disorders.

Reliability and Factorial Validity of Squat and Countermovement Jump Tests

Article

Sep 2004

[Androgen deficiency in women]

Article

Jan 2001

Androgens are defined as the steroids having a binding affinity of the androgen receptor. In the reproduction age a daily production of testosterone is equally divided between the ovaries and adrenal and local tissue conversion of androstenedione and DHEA. After menopause the 80% of testosterone is produced in ovaries, but majority of precursors for peripheral conversion is adrenal origin. Androgen receptors are present throughout in the body; over 200 cellular actions of androgens have been described. Androgenic action is determined by quantitative level of the androgen present in the circulation, its degree of binding to proteins, the degree of interconversion to other androgens and estrogens, and the biological potency and androgen receptor binding affinity of the androgen. The most common clinical symptoms of androgen deficiency are the reduction of sex motivation, sex fantasy, sex enjoyment, sex arousal, vaginal vasocongestion, but also reduction of pubic hair, bone mass, muscle mass, worsening of quality of life (mood, affect, energy), more frequent vasomotors symptoms, insomnia, depression, headache. All these signs and symptoms can be multifactorial. Most common conditions associated with hypoandrogenism in women are hypothalamic-pituitary abnormalities, lack or insufficiency of ovaries, adrenal insufficiency, glucocorticoid therapy, exogenous estrogen administration. Besides the clinical picture the free testosterone measuring is important for diagnosis. The method of choice of this measure is equilibrium dialysis assay. Despite of clinical importance of androgen insufficiency in women, none of methods of androgen substitution is approved by FDA.

Is Testosterone Influencing Explosive Performance?

Abstract

No full-text available

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