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1.
Eur J Sport Sci ; 23(6): 896-903, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35703008

RESUMO

The impact of maternity (Mat) on subsequent athletic performance is not well known. This study aims to investigate the impact of maternity among elite marathoners on their overall performance progression. For each runner listed in the top 150 female marathoners, who had experienced a mid-career maternity, performance development was reconstituted throughout the career. Maternity data and career break time span (Ttotal) were collected from publicly available informations. Performances were modelled according to the known age-performance relationship and the impact of maternity was added into the model. Linear mixed effect model was used to study the influence of maternity on the overall career. Among this sample, 37 runners had at least 1 child during her career. Among them, 14 had 2 children. Eleven runners (29.72%) made their personal best performance before Mat, which occurred at an average age of 28.40 ± 4.00 years. Twenty-six runners (70.28%) establish their best performances after Mat, at an average age of 32.20 ± 4.28. The age-performance relationship model explains 92% of the performance variability during the career's progression. When age is considered, maternity does not have significant impact on performance development. World's most competitive marathoners can still perform at their best level after pregnancy. The ability to return and surpass previous performance level is influenced by the age at which pregnancy occurs, relative to the age of peak performance during career development.HighlightsMid-career maternity does not have a significant impact on overall progression in high level runners, who return to official races.The ability to return and surpass previous performance level is influenced by the age at which pregnancy occurs, relative to the age of peak performance.Age is the variable that explains most of performance progression, independently of mid-career maternity occurrence(s).


Assuntos
Desempenho Atlético , Corrida , Gravidez , Criança , Humanos , Feminino , Adulto Jovem , Adulto , Corrida de Maratona , Logro
2.
Int J Sport Nutr Exerc Metab ; 32(2): 65-73, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808597

RESUMO

BACKGROUND: Exercise and vitamin C-enriched collagen supplementation increase collagen synthesis, potentially increasing matrix density, stiffness, and force transfer. PURPOSE: To determine whether vitamin C-enriched collagen (hydrolyzed collagen [HC] + C) supplementation improves rate of force development (RFD) alongside a strength training program. METHODS: Using a double-blinded parallel design, over 3 weeks, healthy male athletes (n = 50, 18-25 years) were randomly assigned to the intervention (HC + C; 20 g HC + 50 mg vitamin C) or placebo (20 g maltodextrin). Supplements were ingested daily 60 min prior to training. Athletes completed the same targeted maximal muscle power training program. Maximal isometric squats, countermovement jumps, and squat jumps were performed on a force plate at the same time each testing day (baseline, Tests 1, 2, and 3) to measure RFD and maximal force development. Mixed-model analysis of variance compared performance variables across the study timeline, whereas t tests were used to compare the change between baseline and Test 3. RESULTS: Over 3 weeks, maximal RFD in the HC + C group returned to baseline, whereas the placebo group remained depressed (p = .18). While both groups showed a decrease in RFD through Test 2, only the treatment group recovered RFD to baseline by Test 3 (p = .036). In the HC + C group, change in countermovement jumps eccentric deceleration impulse (p = .008) and eccentric deceleration RFD (p = .04) was improved. A strong trend was observed for lower limb stiffness assessed in the countermovement jumps (p = .08). No difference was observed in maximal force or squat jump parameters. CONCLUSION: The HC + C supplementation improved RFD in the squat and countermovement jump alongside training.


Assuntos
Extremidade Inferior , Força Muscular , Adolescente , Adulto , Ácido Ascórbico/farmacologia , Colágeno , Suplementos Nutricionais , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto Jovem
3.
Appl Physiol Nutr Metab ; 46(10): 1179-1188, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33651630

RESUMO

Low energy availability (EA) suppresses many physiological processes, including ovarian function in female athletes. Low EA could also predispose athletes to develop a state of overreaching. This study compared the changes in ad libitum energy intake (EI), exercise energy expenditure (ExEE), and EA among runners completing a training overload (TO) phase. We tested the hypothesis that runners becoming overreached would show decreased EA, suppressed ovarian function and plasma leptin, compared with well-adapted (WA) runners. After 1 menstrual cycle (baseline), 16 eumenorrheic runners performed 4 weeks of TO followed by a 2-week recovery (131 ± 3% and 63 ± 6% of baseline running volume, respectively). Seven-day ExEE, EI, running performance (RUNperf) and plasma leptin concentration were assessed for each phase. Salivary estradiol concentration was measured daily. Urinary luteinizing hormone concentration tests confirmed ovulation. Nine runners adapted positively to TO (WA, ΔRUNperf: +4 ± 2%); 7 were non-functionally overreached (NFOR; ΔRUNperf: -9 ± 2%) as RUNperf remained suppressed after the recovery period. WA increased EI during TO, maintaining their baseline EA despite a large increase in ExEE (ΔEA = +1.9 ± 1.3 kcal·kg fat free mass (FFM)-1·d-1, P = 0.17). By contrast, NFOR showed no change in EI, leading to decreased EA (ΔEA = -5.6 ± 2.1 kcal·kg FFM-1·d-1, P = 0.04). Plasma leptin concentration mid-cycle and luteal salivary estradiol concentration decreased in NFOR only. Contrasting with WA, NFOR failed to maintain baseline EA during TO, resulting in poor performance outcomes and suppressed ovarian function. ClinicalTrials.gov no. NCT02224976. Novelty: Runners adapting positively to training overload (TO) increased ad libitum energy intake, maintaining baseline EA and ovarian function through TO. By contrast, NFOR runners failed to increase energy intake, showing suppressed EA and ovarian function during TO.


Assuntos
Ingestão de Energia , Metabolismo Energético , Ovário/fisiopatologia , Corrida/fisiologia , Adulto , Dismenorreia , Estradiol , Exercício Físico/fisiologia , Fadiga/fisiopatologia , Feminino , Humanos , Leptina/sangue , Ciclo Menstrual , Resistência Física , Carga de Trabalho , Adulto Jovem
4.
PLoS One ; 10(4): e0124776, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25915642

RESUMO

Recent research on whole-body cryotherapy has hypothesized a major responsibility of head cooling in the physiological changes classically reported after a cryostimulation session. The aim of this experiment was to verify this hypothesis by studying the influence of exposing the head to cold during whole-body cryostimulation sessions, on the thermal response and the autonomic nervous system (ANS). Over five consecutive days, two groups of 10 participants performed one whole-body cryostimulation session daily, in one of two different systems; one exposing the whole-body to cold (whole-body cryostimulation, WBC), and the other exposing the whole-body except the head (partial-body cryostimulation, PBC).10 participants constituted a control group (CON) not receiving any cryostimulation. In order to isolate the head-cooling effect on recorded variables, it was ensured that the WBC and PBC systems induced the same decrease in skin temperature for all body regions (mean decrease over the 5 exposures: -8.6°C ± 1.3°C and -8.3 ± 0.7°C for WBC and PBC, respectively), which persisted up to 20-min after the sessions (P20). The WBC sessions caused an almost certain decrease in tympanic temperature from Pre to P20 (-0.28 ± 0.11°C), while it only decreased at P20 (-0.14 ± 0.05°C) after PBC sessions. Heart rate almost certainly decreased after PBC (-8.6%) and WBC (-12.3%) sessions. Resting vagal-related heart rate variability indices (the root-mean square difference of successive normal R-R intervals, RMSSD, and high frequency band, HF) were very likely to almost certainly increased after PBC (RMSSD:+49.1%, HF: +123.3%) and WBC (RMSSD: +38.8%, HF:+70.3%). Plasma norepinephrine concentration was likely increased in similar proportions after PBC and WBC, but only after the first session. Both cryostimulation techniques stimulated the ANS with a predominance of parasympathetic tone activation from the first to the fifth session and in slightly greater proportion with WBC than PBC. The main result of this study indicates that the head exposure to cold during whole-body cryostimulation may not be the main factor responsible for the effects of cryostimulation on the ANS.


Assuntos
Temperatura Baixa , Cabeça , Hipotermia Induzida , Adulto , Sistema Nervoso Autônomo , Pressão Sanguínea , Índice de Massa Corporal , Temperatura Corporal , Peso Corporal , Catecolaminas/sangue , Crioterapia , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso Parassimpático , Adulto Jovem
5.
Med Sci Sports Exerc ; 47(7): 1416-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25314578

RESUMO

INTRODUCTION: Elite athletes frequently undergo periods of intensified training (IT) within their normal training program. These periods can lead athletes into functional overreaching, characterized by high perceived fatigue, impaired sleep, and performance. Because whole-body cryostimulation (WBC) has been proven to be an effective recovery method in the short term (<76 h), we investigated whether daily WBC sessions during IT could prevent exercise and sleep-related signs of overreaching. METHODS: After a normal training week (BASE), 10 elite synchronized swimmers performed two 2-wk IT periods in a randomized crossover fashion using WBC daily (ITWBC) or not (ITCON), separated by 9 d of light training. Swim time trials (400 m) were performed at BASE and after each IT to quantify blood lactate ([La]B), HR (HR400), salivary alpha amylase ([α-amylase]s400), and cortisol ([cortisol]s400) responses. Swimmers wore a wrist actigraph nightly to monitor sleep patterns. RESULTS: Swim speed (400 m), [La]B400, and [α-amylase]s400 decreased from BASE to ITCON, although no significant changes were found after ITWBC. Decreased swim speed was correlated to decreased HR400 and [cortisol]s400. During ITCON, significant decreases in actual sleep duration (-21 ± 7 min) and sleep efficiency (-1.9% ± 0.8%) were observed, with increased sleep latency (+11 ± 5 min) and fatigue compared with BASE, although these variables did not change during ITWBC. Using a qualitative statistical analysis, we observed that daily WBC use resulted in a 98%, 59%, 66%, and 78% chance of preserving these respective variables compared with ITCON. CONCLUSION: WBC use during IT helped mitigate the signs of functional overreaching observed during ITCON, such as reduced sleep quantity, increased fatigue, and impaired exercise capacity. These results support the daily use of WBC by athletes seeking to avoid functional overreaching during key periods of competition preparation.


Assuntos
Crioterapia , Fadiga/prevenção & controle , Transtornos do Sono-Vigília/prevenção & controle , Natação/fisiologia , Actigrafia , Estudos Cross-Over , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/análise , Ácido Láctico/sangue , Saliva/química , Adulto Jovem , alfa-Amilases/análise
6.
J Appl Physiol (1985) ; 117(3): 214-22, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24925979

RESUMO

Functional overreaching (F-OR) induced by heavy load endurance training programs has been associated with reduced heart rate values both at rest and during exercise. Because this phenomenon may reflect an impairment of cardiac response, this research was conducted to test this hypothesis. Thirty-five experienced male triathletes were tested (11 control and 24 overload subjects) before overloading (Pre), immediately after overloading (Mid), and after a 2-wk taper period (Post). Physiological responses were assessed during an incremental cycling protocol to volitional exhaustion, including catecholamines release, oxygen uptake (V̇o2), arteriovenous O2 difference, cardiac output (Q̇), and systolic (SBP) and diastolic blood pressure (DBP). Twelve subjects of the overload group developed signs of F-OR at Mid (decreased performance with concomitant high perceived fatigue), while 12 others did not [acute fatigue group (AF)]. V̇o2max was reduced only in F-OR subjects at Mid. Lower Q̇ and SBP values with greater arteriovenous O2 difference were reported in F-OR subjects at all exercising intensities, while no significant change was observed in the control and AF groups. A concomitant decrease in epinephrine excretion was reported only in the F-OR group. All values returned to baseline at Post. Following an overload endurance training program leading to F-OR, the cardiac response to exhaustive exercise is transiently impaired, possibly due to reduced epinephrine excretion. This finding is likely to explain the complex process of underperformance syndrome experienced by F-OR endurance athletes during heavy load programs.


Assuntos
Adrenérgicos/farmacologia , Epinefrina/farmacologia , Exercício Físico/fisiologia , Coração/efeitos dos fármacos , Coração/fisiologia , Resistência Física/fisiologia , Adulto , Atletas , Ciclismo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Débito Cardíaco/efeitos dos fármacos , Débito Cardíaco/fisiologia , Cardiotônicos/farmacologia , Catecolaminas/metabolismo , Teste de Esforço/métodos , Fadiga/metabolismo , Fadiga/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Norepinefrina/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Educação Física e Treinamento/métodos , Resistência Física/efeitos dos fármacos , Descanso/fisiologia
7.
J Sports Sci ; 32(12): 1146-54, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24580142

RESUMO

In a context of morphological expansion of the general population, how do athletes follow such a pattern of anthropometric growth? Is there any relation to performance? Biometric data including mass, height, body mass index (BMI) and age were collected for 50,376 American athletes representing 249,336 annual performers playing in professional baseball, football, ice hockey and basketball. Distributions by mass in National Football League (NFL) players are described by periods. Field goals have been studied in relation to players' height in the National Basketball Association (NBA). Between 1871 and 2011, athletes from the four sports have increased significantly in mass, height and BMI, following a multi-exponential function series. Consequently, biometric differences between athletes and the general population are increasing gradually. Changes in the mass distribution within the NFL show the emergence of a biometrical specificity in relation to the field position. At the professional level, performance remains structured around precise biometric values. In the NBA, a height-attractor at 201.3 ± 6.3 cm for the best scorers is invariant, regardless of the level of play. These results suggest that laws of growth and biometrics drive high-level sport and organise performance around the specific constraint of each field position. Discrepancies between some mass and height developments question the (disproportionate) large mass increase (relative to the height increase) during the 1980s and 1990s.


Assuntos
Desempenho Atlético/fisiologia , Desempenho Atlético/tendências , Estatura , Índice de Massa Corporal , Esportes/fisiologia , Esportes/tendências , Beisebol/fisiologia , Beisebol/tendências , Basquetebol/fisiologia , Basquetebol/tendências , Biometria , Futebol Americano/fisiologia , Futebol Americano/tendências , Hóquei/fisiologia , Hóquei/tendências , Humanos , Estados Unidos
8.
Med Sci Sports Exerc ; 45(11): 2061-71, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24136138

RESUMO

PURPOSE: We analyzed HR variability (HRV) to detect alterations in autonomic function that may be associated with functional overreaching (F-OR) in endurance athletes. METHODS: Twenty-one trained male triathletes were randomly assigned to either intensified training (n = 13) or normal training (n = 8) groups during 5 wk. HRV measures were taken daily during a 1-wk moderate training (baseline), a 3-wk overload training, and a 1-wk taper. RESULTS: All the subjects of the intensified training group demonstrated a decrease in maximal incremental running test performance at the end of the overload period (-9.0% ± 2.1% of baseline value) followed by a performance supercompensation after the taper and were therefore diagnosed as F-OR. According to a qualitative statistical analysis method, a likely to very likely negative effect of F-OR on HR was observed at rest in supine and standing positions, using isolated seventh-day values and weekly average values, respectively. When considering the values obtained once per week, no clear effect of F-OR on HRV parameters was found. In contrast, the weekly mean of each HRV parameter showed a larger change in indices of parasympathetic tone in the F-OR group than the control group in supine position (with a 96%/4%/0% chance to demonstrate a positive/trivial/negative effect on Ln RMSSD after the overload period; 77%/22%/1% on LnHF) and standing position [98%/1%/1% on Ln RMSSD; 99%/0%/1% on LnHF; 95%/1%/4% on Ln(LF + HF)]. During the taper, theses responses were reversed. CONCLUSIONS: Using daily HRV recordings averaged over each week, this study detected a progressive increase in the parasympathetic modulation of HR in endurance athletes led to F-OR. It also revealed that due to a wide day-to-day variability, isolated, once per week HRV recordings may not detect training-induced autonomic modulations in F-OR athletes.


Assuntos
Frequência Cardíaca , Sistema Nervoso Parassimpático/fisiopatologia , Condicionamento Físico Humano/fisiologia , Resistência Física/fisiologia , Adulto , Ciclismo/fisiologia , Fadiga/etiologia , Fadiga/psicologia , Humanos , Masculino , Condicionamento Físico Humano/efeitos adversos , Postura/fisiologia , Descanso/fisiologia , Corrida/fisiologia , Natação/fisiologia , Adulto Jovem
9.
PLoS One ; 8(8): e72658, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23991134

RESUMO

The aim of this study was to compare the effects of a single whole-body cryostimulation (WBC) and a partial-body cryostimulation (PBC) (i.e., not exposing the head to cold) on indices of parasympathetic activity and blood catecholamines. Two groups of 15 participants were assigned either to a 3-min WBC or PBC session, while 10 participants constituted a control group (CON) not receiving any cryostimulation. Changes in thermal, physiological and subjective variables were recorded before and during the 20-min after each cryostimulation. According to a qualitative statistical analysis, an almost certain decrease in skin temperature was reported for all body regions immediately after the WBC (mean decrease±90% CL, -13.7±0.7°C) and PBC (-8.3±0.3°C), which persisted up to 20-min after the session. The tympanic temperature almost certainly decreased only after the WBC session (-0.32±0.04°C). Systolic and diastolic blood pressures were very likely increased after the WBC session, whereas these changes were trivial in the other groups. In addition, heart rate almost certainly decreased after PBC (-10.9%) and WBC (-15.2%) sessions, in a likely greater proportion for WBC compared to PBC. Resting vagal-related heart rate variability indices (the root-mean square difference of successive normal R-R intervals, RMSSD, and high frequency band, HF) were very likely increased after PBC (RMSSD: +54.4%, HF: +138%) and WBC (RMSSD: +85.2%, HF: +632%) sessions without any marked difference between groups. Plasma norepinephrine concentrations were likely to very likely increased after PBC (+57.4%) and WBC (+76.2%), respectively. Finally, cold and comfort sensations were almost certainly altered after WBC and PBC, sensation of discomfort being likely more pronounced after WBC than PBC. Both acute cryostimulation techniques effectively stimulated the autonomic nervous system (ANS), with a predominance of parasympathetic tone activation. The results of this study also suggest that a whole-body cold exposure induced a larger stimulation of the ANS compared to partial-body cold exposure.


Assuntos
Catecolaminas/sangue , Temperatura Baixa , Sistema Nervoso Parassimpático/fisiologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Appl Physiol Nutr Metab ; 38(2): 126-33, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23438222

RESUMO

This study investigated the effect of whole-body cryostimulation (WBC), contrast-water therapy (CWT), active recovery (ACT), and passive condition (PAS) protocols on the parasympathetic reactivation and metabolic parameters of recovery in elite synchronized swimmers who performed 2 simulated competition ballets (B1 and B2) separated by 70 min. After determining maximal oxygen consumption (V̇O(2max400)) and blood lactate concentrations ([La(-)](b400)) during a 400-m swim trial, 11 swimmers performed 1 protocol per week in randomized order. Heart rate variability (HRV) was measured at rest (PreB1), 5 min after B1 (PostB1), before B2 (PreB2), and 5 min after B2 (PostB2). V̇O(2peak) was measured at PostB1 and PostB2, and [La(-)](b) was measured at PostB1, PreB2, and PostB2. PostB1 V̇O(2peak) and V̇O(2max400) were similar, but PostB1 [La(-)](b) was higher than [La(-)](b400) (p = 0.004). Each ballet caused significant decreases in HRV indices. At PreB2, all HRV indices had returned to PreB1 levels in the CWT, PAS, and ACT protocols, whereas the WBC protocol yielded a 2- to 4-fold increase in vagal-related HRV indices, compared with PreB1. WBC and ACT both increased [La(-)](b) recovery, compared with PAS (p = 0.06 and p = 0.04, respectively), and yielded an increased V̇O(2peak) from B1 to B2; however, it decreased after PAS (+5.4%, +3.4%, and -3.6%; p < 0.01). This study describes the physiological response to repeated maximal work bouts that are highly specific to elite synchronized swimming. In the context of short-term recovery, WBC yields a strong parasympathetic reactivation, and shows similar effectiveness to ACT on the metabolic parameters of recovery and subsequent exercise capacity.


Assuntos
Exercício Físico/fisiologia , Nervo Vago/fisiologia , Metabolismo Energético , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Adulto Jovem
11.
PLoS One ; 6(5): e19007, 2011 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-21573222

RESUMO

OBJECTIVES: Few epidemiological studies have focused on the psychological health of high level athletes. This study aimed to identify the principal psychological problems encountered within French high level athletes, and the variations in their prevalence based on sex and the sport practiced. METHODS: Multivariate analyses were conducted on nationwide data obtained from the athletes' yearly psychological evaluations. RESULTS: A representative sample of 13% of the French athlete population was obtained. 17% of athletes have at least one ongoing or recent disorder, generalized anxiety disorder (GAD) being the most prevalent (6%), followed by non-specific eating disorders (4.2%). Overall, 20.2% of women had at least one psychopathology, against 15.1% in men. This female predominance applied to anxiety and eating disorders, depression, sleep problems and self-harming behaviors. The highest rates of GAD appeared in aesthetic sports (16.7% vs. 6.8% in other sports for men and 38.9% vs. 10.3% for women); the lowest prevalence was found in high risk sports athletes (3.0% vs. 3.5%). Eating disorders are most common among women in racing sports (14% vs. 9%), but for men were found mostly in combat sports (7% vs. 4.8%). DISCUSSION: This study highlights important differences in psychopathology between male and female athletes, demonstrating that the many sex-based differences reported in the general population apply to elite athletes. While the prevalence of psychological problems is no higher than in the general population, the variations in psychopathology in different sports suggest that specific constraints could influence the development of some disorders.


Assuntos
Atletas/psicologia , Esportes/psicologia , Adolescente , Adulto , Transtornos de Ansiedade/epidemiologia , Criança , Depressão/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Feminino , Humanos , Masculino , Análise Multivariada , Fatores Sexuais , Transtornos do Sono-Vigília/epidemiologia , Adulto Jovem
12.
Med Sci Sports Exerc ; 43(11): 2148-54, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21502889

RESUMO

INTRODUCTION: The victory percentages for tennis players who entered the top 10 women and men rankings show various evolutions related to age and time since 1968. METHODS: The study analyzed the careers of all top 10 players: 97 women (50,933 matches) and 144 men (92,450 matches). For each player, we describe a biphasic performance course. Two generations were compared: the first one (G1), including players who started their professional career before 1985, and the second one (G2), with players starting after 1985. RESULTS: The average career length is 16.1 ± 3.8 yr for the top 10 men and 15.8 ± 4.4 yr for women. Compared with G1 players, G2 players begin earlier (women = 1.3 yr, men = 0.8 yr), but career length remains the same. An exponential model describes the time course of the victory percentage with a great similarity for both genders. Using this equation, the peak victory rate reaches 82.5% at 21.5 yr for number 1 (no. 1) women and 78.5% at 23.7 yr for no. 1 men, showing a greater precocity and earlier decline in women. Finally, the area under the curve shows a potential that is 22.8% (men) to 56.8% (women) larger for the no. 1 players as compared with all other numbers 2-10. CONCLUSIONS: Tennis players in the top 10 show a biphasic career. Women reach their highest level earlier than men, consistent with their more precocious biological development. For the current generation, the peak performance tends toward a younger age than the first generation. We show how to precisely quantify and compare tennis performances using indicators that follow the trends of development and aging and demonstrate that precocity does not provide a larger victory potential.


Assuntos
Envelhecimento , Atletas , Competência Profissional , Tênis , Adolescente , Adulto , Bases de Dados Factuais , Feminino , França , Humanos , Masculino , Adulto Jovem
13.
Med Sci Sports Exerc ; 43(1): 34-43, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20508538

RESUMO

PURPOSE: We examined the catecholamine response to exercise in five eumenorrheic (EU) and five amenorrheic (AM) athletes, matched by age (mean ± SEM: EU = 29.8 ± 2.5 yr and AM = 31.0 ± 4.3 yr) and running volume (EU = 56.4 ± 8.1 km·wk(-1) and AM = 61.5 ± 6.4 km·wk(-1)). METHODS: Subjects performed a maximal treadmill test followed by a 30-min recovery and then a submaximal running test, consisting of 4-min stages at 60%, 70%, and 80% and 15 min at 85% of peak oxygen consumption (VO(2peak)). Blood was drawn after each stage to measure glucose, lactate, epinephrine, norepinephrine, and cortisol concentrations. HR, blood pressure, and rate of perceived exertion were also measured at each stage. RESULTS: There were no differences between groups in body composition or VO(2peak) (EU = 57.3 ± 2.3 mL·kg(-1)·min(-1) and AM = 54.1 ± 1.2 mL·kg(-1)·min(-1). Resting HR and mean arterial pressure were significantly (P ≤ 0.05) lower in AM. Norepinephrine was lower in AM at 70%, 80%, 85%, and 100% of VO(2peak) (EU = 7784.5 ± 582.9 pg·mL(-1) and AM = 3626.1 ± 271.4 pg·mL(-1) at VO(2peak)). Epinephrine (EU = 1470.3 ± 275.1 pg·mL(-1) and AM = 416.9 ± 67.5 pg·mL(-1)) and blood lactate (EU = 10.1 ± 1.2 mmol·L(-1) and AM = 6.7 ± 0.9 mmol·L(-1)) were lower at VO(2peak) in AM. CONCLUSIONS: Our results demonstrate a reduced adrenergic response to intense exercise in AM athletes as indicated by reduced blood lactate and catecholamine concentrations. A suppressed catecholamine response could decrease performance by reducing the sympathetic drive essential for the cardiovascular and metabolic adjustments needed to maintain high intensities of exercise.


Assuntos
Amenorreia/metabolismo , Atletas , Epinefrina/sangue , Exercício Físico/fisiologia , Norepinefrina/sangue , Adulto , Amenorreia/sangue , Amenorreia/etiologia , Amenorreia/psicologia , Glicemia/análise , Pressão Sanguínea , Estudos de Casos e Controles , Metabolismo Energético , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Hidrocortisona/sangue , Ácido Láctico/sangue , Consumo de Oxigênio , Esforço Físico
14.
J Sports Sci Med ; 9(2): 214-23, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-24149688

RESUMO

Sex is a major factor influencing best performances and world records. Here the evolution of the difference between men and women's best performances is characterized through the analysis of 82 quantifiable events since the beginning of the Olympic era. For each event in swimming, athletics, track cycling, weightlifting and speed skating the gender gap is fitted to compare male and female records. It is also studied through the best performance of the top 10 performers in each gender for swimming and athletics. A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events. The gender gap ranges from 5.5% (800-m freestyle, swimming) to 18.8% (long jump). The mean gap is 10.7% for running performances, 17.5% for jumps, 8.9% for swimming races, 7.0% for speed skating and 8.7% in cycling. The top ten performers' analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%, despite the large growth in participation of women from eastern and western countries, that coincided with later- published evidence of state-institutionalized or individual doping. These results suggest that women will not run, jump, swim or ride as fast as men. Key pointsSex is a major factor influencing best performances and world records.A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events.The gender gap ranges from 5.5% (800-m freestyle, swimming) to 36.8% (weight lifting).The top ten performers' analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%.Results suggest that women will not run, jump, swim or ride as fast as men.

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