Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Int J Sports Med ; 37(7): 559-64, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27116347

RESUMO

This study used functional magnetic resonance imaging (fMRI) to compare individual muscle use in exercises aimed at preventing hamstring injuries. Thirty-six professional soccer players were randomized into 4 groups, each performing either Nordic hamstring, flywheel leg curl, Russian belt or conic-pulley exercise. MRIs were performed before and immediately after a bout of 4 sets of 8 repetitions. Pre-post exercise differences in contrast shift (T2) were analyzed for the long (BFLh) and short head (BFSh) of biceps femoris, semitendinosus (ST), semimembranosus (SM) and gracilis (GR) muscles. Flywheel leg curl increased (P<0.001) T2 of GR (95%), ST (65%), BFSh (51%) and BFLh (14%). After the Nordic hamstring, GR (39%), ST (16%) and BFSh (14%) showed increased T2 (P<0.001). Russian belt and conic-pulley exercise produced subtle (P<0.02) T2 increases of ST (9 and 6%, respectively) and BFLh (7 and 6%, respectively). Russian belt increased T2 of SM (7%). Among exercises examined, flywheel leg curl showed the most substantial hamstring and GR muscle use. However, no single exercise executed was able to increase T2 of all hamstring and synergist muscles analyzed. It is therefore suggested that multiple exercises must be carried out to bring in, and fully activate all knee flexors and hip extensors.


Assuntos
Músculos Isquiossurais/diagnóstico por imagem , Músculos Isquiossurais/fisiologia , Treinamento Resistido/métodos , Futebol/fisiologia , Adolescente , Traumatismos em Atletas/prevenção & controle , Humanos , Perna (Membro) , Imageamento por Ressonância Magnética , Adulto Jovem
2.
Int J Sports Med ; 34(6): 526-32, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23184481

RESUMO

The purpose of this study was to compare motions of soccer players in the English Premier (1st) and Championship (2nd) League. A total of 26 449 observations were obtained from players during 4 seasons (2006-2010) in the 2 leagues. Time-motions of all players (attackers, central defenders, central midfielders, wide defenders, wide midfielders) were recorded during each match using the Prozone® System, (Leeds, UK), and categorized by speed intensity. Number of actions, total distance and the mean distance covered at each speed intensity were measured. Players in the Championship league covered a total match distance of 11.1±0.9 km compared with 10.8±1.0 km for players from the Premiership (p<0.001). Championship players also covered greater distances during jogging, running, high-speed running, and sprinting. Premiership players covered more distance walking. Players in the Soccer League Championship had more instances of each condition. Although these differences were statistically significant, they were negligible in practical terms, suggesting match-related activities do not explain the general superiority of Premiership players over Championship players in England.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Caminhada/fisiologia , Atletas , Inglaterra , Humanos , Fatores de Tempo , Estudos de Tempo e Movimento
3.
Int J Sports Med ; 30(3): 205-12, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19214939

RESUMO

The aim of the present investigation was to provide a detailed analysis of the high intensity running activity completed by elite soccer players during match-play. A further aim of the study was to evaluate the importance of high intensity running activity to overall team success. Observations on individual match performance measures were undertaken on 563 outfield players (median of 8 games per player; range=1-57) competing in the English Premier League from 2003/2004 to 2005/2006 using a computerised tracking system (Prozone, Leeds, England). High intensity activities selected for analysis included total high intensity running distance (THIR), total sprint distance (TSD) and the number and type of sprints undertaken. Total high intensity running distance in possession and without possession of the ball was also analysed. The THIR was dependant upon playing position with wide midfield (1,049+/-106 m) and central defenders (681+/-128 m) completing the highest and lowest distance respectively (p<0.001). High intensity activity was also related to team success with teams finishing in the bottom five (919+/-128 m) and middle ten (917+/-143 m) league positions completing significantly more THIR compared with teams in the top five (885+/-113 m) (p=0.003). The THIR and TSD also significantly declined during the 2nd half with the greatest decrements observed in wide midfield and attacking players (p<0.05). Both positional differences in high intensity activity and the observed change in activity throughout the game were also influenced by team success (p<0.05). The results of the present study indicate that high intensity activity in elite soccer match-play is influenced by both playing position and previous activity in the game. These activity patterns are also dependant upon success of the team. This may indicate that overall technical and tactical effectiveness of the team rather than high levels of physical performance per se are more important in determining success in soccer.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Inglaterra , Fadiga , Humanos , Processamento de Imagem Assistida por Computador , Resistência Física/fisiologia
4.
J Sports Med Phys Fitness ; 48(4): 443-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18997646

RESUMO

AIM: The purpose of this study was to analyse the activities of a goalkeeper during a match and to identify the distances covered at different velocities between the first and second halves. METHODS: Sixty-two goalkeepers belonging to 28 teams in the English Premier League were monitored over 109 matches using the Prozone(R) system. All values are averages and standard deviations. Pearson product moment correlation was used to examine selected bivariate correlation. To analyze the differences in averages, the paired Student t-test was used. The analyses were performed using SPSS (v.13.0; SPSS, Inc. Chicago, IL). The significance level was set at P<0.05. RESULTS: Mean total distance covered by the goalkeeper during the match was 5 611+/-613 m. There were no differences between distances covered in the first and second halves. The distance covered at high-intensity was 56+/-34 m, while the distance covered sprinting was 11+/-12 m. The average number of high speed actions was 10+/-6, with a total range between 0 and 40. The goalkeeper walked during 73% of the match, while spending just 2% moving at high-intensity. CONCLUSION: The goalkeeper's physical activity was not as great as that of the field players, but the high-intensity actions carried out will be very decisive in the final result of the match.


Assuntos
Atividade Motora/fisiologia , Aptidão Física/fisiologia , Futebol/fisiologia , Desempenho Atlético/fisiologia , Humanos , Masculino , Reino Unido
5.
J Sports Med Phys Fitness ; 47(4): 422-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18091682

RESUMO

AIM: Oxaloacetic acid represents a fundamental intermediary in the metabolism of energy substrate. Asparagine and aspartate constitute precursor compounds of this substance. Therefore, they could affect tricarbossilic acids cycle. Besides, it was suggested that supplementation with aspartate and asparagine determines a muscular glycogen sparing during strenuous physical exercise, even if the real effectiveness remain controversial. The aim of the present pilot study was to evaluate the hypothesis that a supplementation with oxaloacetate precursors, precisely aspartate and asparagine, could improve sport performance during high intensity endurance exercise. METHODS: We recruited 15 male trained athletes, aged from 20 to 30 years (mean age: 24.13+/-3.87 years), practicing triathlon. We administered them placebo or aspartate (7 g) and asparagine (7 g) mixture, using a double blind technique, before performing an exhaustion stress test on cycloergometer carried out to 90% of each athlete's maximum oxygen consumption, previously determined. RESULTS: We evaluated lactatemia through earlobe punctures at the end of warming up, at the maximum effort and at recovery time (3 min, 5 min, 10 min, 15 min, 30 min). Furthermore, subjects were submitted to three blood samples from brachial artery in order to assess the glycemia (before the exercise, at the end of the exercise, and 30 min after the end of the exercise). CONCLUSION: The analysis of these parameters and the results of the ergometric tests after amino acids assumption indicate that acute supplementation with aspartate and asparagine do not significantly affect physical performance in athletes practicing high intensity exercises, and that acute administration of aspartate does not cause a sparing of muscle glycogen concentration.


Assuntos
Asparagina/administração & dosagem , Ácido Aspártico/administração & dosagem , Exercício Físico/fisiologia , Fadiga/induzido quimicamente , Adulto , Asparagina/metabolismo , Ácido Aspártico/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Humanos , Itália , Masculino , Aptidão Física , Placebos
6.
J Sports Med Phys Fitness ; 47(2): 191-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17557057

RESUMO

AIM: The aim of this study was to describe and evaluate physiological parameters as a control tool for the monitoring of training in a group of elite cyclists during one season of training. METHODS: The study is divided into two periods (winter or ''volume'' mesocycle and spring or ''intensity'' mesocycle) between the tests that they carried out in the laboratory, consisting of a ramp test to exhaustion (work load increases 25 W X min(-1)) and a maximal lactate steady state (MLSS) test on a cycle ergometer. Macronutrients and hematological variables were recorded during the test periods as were the volume and the intensity of training sessions during the whole period of the study. RESULTS: The physiological data were similar to those previously reported for professional cyclists (approximately 450 Watts, approximately 78 mL x kg(-1) x min(-1)) and the values for the MLSS also agree with previous studies (approximately 250 Watts). Subjects improved the first ventilatory threshold (VT(1)) (approximately 52% to approximately 60% VO(2max)) and the second ventilatory threshold (VT(2)) (approximately 82% to approximately 87% VO(2max)) after the first period of training even though its low intensity focused on the performance of VT(1) (77% training in ''zone 1'', under VT(1)). The MLSS improved after the first period (approximately 225 to approximately 250 Watts) and remained high in the second (approximately 255 Watts). High levels of creatine kinase (approximately 230 U x L(-1)) and urea (37 mg x L(-1)) were found, also a decrease in hemoglobin values (approximately 15.4 to approximately 14.7g x dL(-1)). CONCLUSION: The high level reached by the subjects after the first period of training suggests that two effort tests could be enough to plan training. On the other hand, the decrease in some red blood cell and nutrition parameters suggests that there should be greater control over them during the season.


Assuntos
Ciclismo/fisiologia , Educação Física e Treinamento/métodos , Adulto , Análise de Variância , Teste de Esforço , Hemoglobinas/análise , Humanos , Lactatos/sangue , Estudos Longitudinais , Masculino , Estado Nutricional , Consumo de Oxigênio/fisiologia , Ureia/sangue
7.
Int J Sports Med ; 28(3): 222-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17024626

RESUMO

The paper provides a large-scale study into the motion characteristics of top class soccer players, during match play, according to playing position. Three hundred top-class outfield soccer players were monitored during 20 Spanish Premier League and 10 Champions League games using a computerized match analysis system (Amisco Pro, Nice, France). Total distance covered in five selected categories of intensity, and the mean percentage of playing time spent in each activity were analyzed according to playing position. Midfield players covered a significantly greater total distance (p < 0.0001) than the groups of defenders and forwards did. Analyzing the different work rates showed significant differences (p < 0.5 - 0.0001) between the different playing positions. There were no significant differences between halves in the total distance covered, or in distances covered at submaximal and maximal intensities. However, significantly more distance was covered in the first half compared to the second in medium intensities (11.1 - 19 km/h). The current findings provide a detailed description of the demands placed on elite soccer players, according to their positional role at different work intensities, which may be helpful in the development of individualized training programs.


Assuntos
Papel (figurativo) , Futebol , Estudos de Tempo e Movimento , Humanos , Gravação em Vídeo
8.
J Sports Med Phys Fitness ; 46(4): 598-604, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17119526

RESUMO

AIM: Power spectral analysis of heart rate variability has been used to assess the time course of neurovegetative adaptations to training. This study was undertaken: 1) to evaluate whether and which indicator(s) of autonomic cardiac regulation and psychophysical stress can identify successful athletes during a training season culminating with the Olympic Games and 2) to evaluate the feasibility of a quasi-on-line assessment of autonomic cardiac regulation from training field, by a telematic approach. METHODS: This study was conducted on the group of male athletes composing the Italian national team of rowing (n=34), in the season preceding the 2004 Olympic Games. Complete results are from 18 subjects (age 25.3+/-0.5 years), who were selected to participate to the Athens' Olympic games. Athletes were studied while partially detrained, at mid-training season and close to the games. The RR interval was obtained through a miniature transtelephonic-ECG recorder in the supine and standing posture, thus allowing the evaluation of cardiovascular responses to a sympathetic challenge. Data were downloaded through a telephone line, to the referral center where RR-interval variability data were analyzed with the autoregressive method. Also, in each study sessions, athletes filled a self-administered questionnaire of stress perception and somatic symptoms (4S-Q). RESULTS: All ECG recordings were transmitted successfully by phone to the referral center. No significant difference was detected in any marker of autonomic cardiac regulation between athletes who won a medal at the Olympic Games and those who did not. However, respiratory rate was faster in medal winners (P=0.02), while the questionnaire addressing stress (4S-Q) provided greater scores in the group that did not win a medal (F=5.55, P<0.022) at mid-training season and close to the Olympic Games. CONCLUSIONS: The results of this study would suggest the possibility of an early detection of psychosomatic symptoms resulting from long duration and elevated stress of preparing for top level competitions, whose better handling might identify the most successful athletes. In addition, it indicates the feasibility of a quasi-on-line assessment of autonomic cardiac adaptations to strenuous training directly from field to be possibly used for improving individual training programs, allowing athletes evaluation in their natural environment.


Assuntos
Adaptação Fisiológica/fisiologia , Adaptação Psicológica/fisiologia , Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/fisiologia , Esportes/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Eletrocardiografia , Humanos , Masculino , Aptidão Física/fisiologia , Estresse Psicológico , Telecomunicações
9.
Br J Sports Med ; 39(8): 527-31, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16046336

RESUMO

BACKGROUND: The effectiveness of cardiovascular screening in minimising the risk of athletic field deaths in master athletes is not known. OBJECTIVE: To evaluate the prevalence and clinical significance of ST segment depression during a stress test in asymptomatic apparently healthy elderly athletes. METHODS: A total of 113 male subjects aged over 60 were studied (79 trained and 34 sedentary); 88 of them (62 trained and 26 sedentary) were followed up for four years (mean 2.16 years for athletes, 1.26 years for sedentary subjects), with a resting 12 lead electrocardiogram (ECG), symptom limited exercise ECG on a cycle ergometer, echocardiography, and 24 hour ECG Holter monitoring. RESULTS: A significant ST segment depression at peak exercise was detected in one athlete at the first evaluation. A further case was seen during the follow up period in a previously "negative" athlete. Both were asymptomatic, and single photon emission tomography and/or stress echocardiography were negative for myocardial ischaemia. The athletes remained symptom-free during the period of the study. One athlete died during the follow up for coronary artery disease: he showed polymorphous ventricular tachycardia during both the exercise test and Holter monitoring, but no significant ST segment depression. CONCLUSIONS: The finding of false positive ST segment depression in elderly athletes, although still not fully understood, may be related to the physiological cardiac remodelling induced by regular training. Thus athletes with exercise induced ST segment depression, with no associated symptoms and/or complex ventricular arrhythmias, and no adverse findings at second level cardiological testing, should be considered free from coronary disease and safe to continue athletic training.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Ecocardiografia sob Estresse/métodos , Esportes/fisiologia , Fatores Etários , Doenças Cardiovasculares/mortalidade , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/prevenção & controle , Eletrocardiografia/métodos , Eletrocardiografia Ambulatorial/métodos , Teste de Esforço/métodos , Seguimentos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/prevenção & controle
10.
J Sports Med Phys Fitness ; 44(1): 92-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15181396

RESUMO

AIM: Physical activity, when vigorous, is not devoided of arrhythmic risk. Since the risk of developing arrhythmias increase as an otherwise healthy person ages, the question arises as to whether high intensity physical activity could be dangerous in the elderly person. The present study addressed the incidence of arrhythmias in elderly athletes in comparison to age-matched control subjects. METHODS: We studied 49 male athletes engaged in various sport disciplines, mean age 62.3+/-2.3 and 24 sedentary or moderately physically active healthy males, mean age 62.9+/-1.7 years (Controls). All subjects underwent 2-D, M-mode and Doppler echocardiographic examination, resting ECG and exercise stress test followed by 24-hour electrocardiographic monitoring. RESULTS: No pathological findings were detected in both experimental groups at echocardiographic examination. Exercise performance was greater in athletes than controls (206.9+/-5.2 vs 156.3+/-12 watt, p<0.01). During exercise test, no significant between-groups difference was detected in the incidence of ventricular arrhythmias, that is multiple premature ventricular contractions (MPVC), polymorphous premature ventricular contractions (PPVC) and repetitive premature ventricular contractions (RPVC). No subject featured horizontal or downsloping ST segment depression in both groups. At 24-hour electrocardiographic monitoring the incidence of the overall number of premature ventricular contractions was significantly greater in controls than athletes (87.0% vs 63.3%, p<0.05), whereas no significant difference were detected in the incidence of discrete ventricular arrhythmias between athletes (4.1% MPVC, 14.3% PPVC, 8.2% couplets) and controls (0.5% MPVC, 16.7% PPVC, 12.5% couplets). CONCLUSION: These finding indicate that in elderly, otherwise healthy, athletes vigorous training even to competition does not result in a greater incidence of ventricular arrhythmias, although caution should be made for a careful preparticipation evaluation.


Assuntos
Arritmias Cardíacas/epidemiologia , Exercício Físico/fisiologia , Ventrículos do Coração/fisiopatologia , Fatores Etários , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiologia , Ecocardiografia , Eletrocardiografia Ambulatorial , Teste de Esforço , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Esportes/fisiologia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/etiologia
11.
J Sports Med Phys Fitness ; 44(3): 288-93, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15756168

RESUMO

AIM: The goal of this prospective randomized study was to compare the isokinetic recovery of thigh strength after anterior cruciate ligament (ACL) reconstruction by using patellar or quadriceps tendon as graft at the 6th month follow-up. METHODS: The authors evaluated 48 patients who underwent arthroscopic ACL reconstruction using patellar tendon (PT group) or quadriceps tendon (QT group) as autograft after a 6 months follow-up undergoing the following tests: the Ergojump Bosco System springboard and Universal's FITNET computerized isokinetic system. RESULTS: The counter movement jump (CMJ) test showed a 24% (p<0.01) strength deficit in patients operated with patellar tendon and 11% in the quadriceps tendon group. Also in the leg press test the greater differences in strength (p<0.05) were verified in the patellar tendon group, above all the peak torque (PT) test carried out at 3 repetitions (15%). CONCLUSIONS: The strength deficit found in the subjects operated with quadriceps tendon were statistically lower in comparison to that verified in the patellar tendon group. A good recovery in thigh strength after 6 months in patients operated with quadriceps tendon could encourage the use of this kind of graft in order to achieve an easier rehabilitation and a faster release of the patient to daily and sports activity.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Músculo Esquelético/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Transferência Tendinosa/métodos , Tendões/transplante , Adulto , Lesões do Ligamento Cruzado Anterior , Artroscopia , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Estudos Prospectivos
12.
J Sports Med Phys Fitness ; 43(4): 535-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14767417

RESUMO

AIM: The present study was carried out to investigate whether oral theophylline supplementation exerts an ergogenic effect during intermittent high-intensity exercise. METHODS: Ten healthy subjects undertook intermittent exercise (1 min cycling at 120% of VO(2max) with 3 min of recovery until exhaustion). The exercise test was repeated twice, 1 week apart. On each occasion, the subject ingested, in a double blind setting, either theophylline (4.5 mg/kg) or placebo 90 min before commencing the exercise test. RESULTS: Three subjects could not complete both trials due to nausea and dizziness after theophylline had been administered. Time to exhaustion in the remaining subjects was slightly increased after theophylline administration (55.9+/-6 min vs 59.3+/-5.9 min; p<0.05). CONCLUSION: Present data indicate that oral theophylline supplementation delays fatigue onset during intermittent high-intensity exercise. The effect, although statistically significant, does not appear to be marked. The possibility of occurrence of negative side effects and the evidence for its ergogenic potential suggests the necessity to include theophylline in the International Olympic Committee (IOC) World Antidoping Agency (WADA) list as a banned or restricted substance.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Tolerância ao Exercício/efeitos dos fármacos , Teofilina/farmacologia , Administração Oral , Adulto , Método Duplo-Cego , Teste de Esforço , Humanos , Masculino
13.
J Sports Med Phys Fitness ; 43(4): 539-45, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14767418

RESUMO

AIM: Stressful situations affect autonomic nervous system activity and hormonal responses. This study aimed to investigate the effects of the stress of sports competition on both endocrine system functioning and neurovegetative control of heart rate (HR) in elite athletes. METHODS: In 7 top-level pentathletes salivary cortisol levels and autoregressive power spectral analysis of HR variability (HRV) were assessed in the morning and in the afternoon on a regular training day (control) and on the day of a competitive selection trial, held 4 weeks apart. RESULTS: HR, as well as low (LF) and high (HF) frequency components of HRV did not differ significantly both between and within the control and the trial days. On the selection day, morning cortisol levels were significant and markedly greater than on the control day and increased further in the afternoon in contrast to the control day, when cortisol levels decreased in the afternoon as expected from the normal diurnal variation. CONCLUSION: These results would indicate a dissociation of the neural and hypothalamic-pituitary-adrenal axis functioning in response to the stress of competition in elite athletes, and the considerable extent to which competition may alter selectively the physiology of stress-related hormones while sparing autonomic cardiac regulation.


Assuntos
Homeostase , Hidrocortisona/metabolismo , Esportes/psicologia , Estresse Psicológico/metabolismo , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Esportes/fisiologia , Estresse Psicológico/fisiopatologia
14.
J Sports Med Phys Fitness ; 42(2): 214-6, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12032418

RESUMO

People practising regular physical activity usually drink hydrosaline beverages. In this study is reported the case of a young football player suffering from premature ventricular beats. He used to take regularly an hydrosaline supplementation which gave him a daily intake of potassium of about 5 g. A stress test on a cycle ergometer showed many monomorphus premature ventricular beats which disappeared when the heart rate was higher than 110 beats/min. Moreover, 3629 polimorphus premature ventricular beats were recorded during a 24 hr ECG monitoring. At the time of the first examination, the plasma potassium concentration was 7,8 mEq x l(-1). The football player was then suspended from practicing sport and he was asked to stop his intake of potassium. The clinical examination was repeated after 3 and 6 months and no ventricular arrhythmias were observed during the stress test as well as during the 24 hours ECG monitoring. The plasma potassium concentration was normal again. The present case report is an example of how the misuse of saline supplementations could result in hyperkalemia and how this condition may lead to ventricular arrhythmias.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Bebidas/efeitos adversos , Futebol Americano , Hiperpotassemia/complicações , Potássio/efeitos adversos , Adolescente , Humanos , Hiperpotassemia/induzido quimicamente , Masculino
15.
Int J Sports Med ; 22(4): 250-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11414665

RESUMO

An Olympic gold medalist in a 20 km competitive walking race and his identical twin brother, also an Olympic athlete in the same event but with inferior performance, were tested in order to obtain some further insight into the relative importance of genetic factors in modulating athletic excellence. Both twins had undergone the same strenuous, long-term training for 19 years since the age of 15 under the guidance of the same coach. An assessment of their bio-behavioural profiles at 40 years of age, i. e. 7 years after they ceased training, revealed that intrapair differences were negligible in physiological attributes but divergent in personality traits measured. Respective values for the Olympic winner and his identical counterpart were as follows: Body mass index 23.2 and 22.7, cardiac mass index 85.4 and 84.4 g x m2, squatjumping 25.3 and 27.3 cm, VO2 at running speed 9 km x h(-1) 33.1 and 33.6 ml x kg(-1) x min(-1), VO2 max 57.1 and 58.6 ml x kg(-1) x min(-1) (72.5ml x kg(-1) x min(-1) for the Olympic winner at age 22 yrs), reaction to anger 97 and 9 and anger expression 2 and 76 in percentile of the State-Trait Anger Expression Inventory. Findings suggest that although genetic constitution and years of physical training are prerequisites for making an Olympic athlete, success may be largely influenced by personality traits.


Assuntos
Personalidade/fisiologia , Gêmeos/genética , Gêmeos/psicologia , Caminhada/fisiologia , Adulto , Análise de Variância , Comportamento Competitivo/fisiologia , Humanos , Masculino , Análise e Desempenho de Tarefas
16.
J Sports Med Phys Fitness ; 41(1): 101-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11317156

RESUMO

BACKGROUND: The aim of this study was to investigate the effects of exercise training on autonomic regulation of heart rate under daily life conditions. METHODS: Twenty-six healthy female athletes (age 24.5 +/- 1.9 yrs) involved in regular physical activity were recruited during a period of yearly rest and randomly assigned to a five-week aerobic exercise training program (n = 13) or to a non-exercise control group (n = 13). MEASURES: Before and after the five-week training, all subjects underwent a bycicle ergometer stress test and a 24-hour dynamic ECG monitoring. Autonomic regulation of heart rate has been investigated by means of both time and frequency domain analyses of heart rate variability (HRV). Spectral analysis of R-R interval variability (autoregressive algorithm) provided markers of sympathetic (low frequency, LF, 0.10 Hz) and parasympathetic (high frequency, HF, 0.25 Hz) modulation of the sinus node. RESULTS: Trained subjects showed a reduced heart rate response to submaximal workload. Before training there was no significant difference between the two groups. After training resting heart rate did not significantly differ between trained and untrained subjects. No significant differences were observed in the different time domain indexes of heart rate variability. The day-night difference in SD and SDRR were significantly less in the trained as compared to the untrained group. Normalized LF and HF components did not significantly differ between trained and untrained subjects, during the awake period. The decrease in the LF and the increase in the HF component during nighttime were significantly less in the trained group. The LF/HF ratio was significantly decreased during the night in the untrained group whereas it was not significantly different from the awake state in the trained group. CONCLUSIONS: These findings of the relative night-time increase in LF and the decrease in the day-night difference in time domain indexes of heart rate variability suggest that, in young female athletes, exercise training is able to induce an increase in the sympathetic modulation of the sinus node which may coexist with signs of relatively reduced, or unaffected, vagal modulation.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Adulto , Eletrocardiografia Ambulatorial , Ergometria , Feminino , Humanos
17.
J Sports Med Phys Fitness ; 40(4): 356-61, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11297007

RESUMO

BACKGROUND: To evaluate the efficacy of extracorporeal shockwaves therapy (ESWT) in patients with chronic painful shoulder. EXPERIMENTAL DESIGN: a prospective design was used with a short term follow-up. SETTING: data were collected at the Service of Physioterapy in Villa Stuart Clinic-Rome. PATIENTS: 72 patients of both sexes with an average age of 38 years (range 18 to 69) affected by chronic painful shoulder, whose symptoms lasted more than 6 months. INTERVENTIONS: all patients received on average, 2,000 impulses of ESWT at level 5 energy (0.21 mJ/mm2) according to Dornier Epos equipment one session per week for 8 weeks. MEASURES: all cases underwent an instrumental examination with X-ray conventional imaging and clinical assessment of pain (visual analogue scale) and functional limitation of the shoulder, two weeks before the treatment and at one month follow-up. RESULTS: 53% of patient scored excellent results, 14% good, 13% fair and 20% poor. In the group of calcifying tendinitis we had a reduction in 37% and no changes in 63%. CONCLUSIONS: Even with a limited number of cases our early results show the efficacy and safety of ESWT in the treatment of chronic painful shoulder resistant to other conservative approaches.


Assuntos
Ondas de Choque de Alta Energia , Dor de Ombro/terapia , Adolescente , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Lesões do Manguito Rotador , Resultado do Tratamento
18.
J Sports Med Phys Fitness ; 38(4): 294-7, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9973771

RESUMO

BACKGROUND: The aim of this study was to evaluate the relative effectiveness of an individualized training programme for football players according to their positions in the team, by comparing it with a programme which did not differentiate roles, but utilized the same means for training. METHODS: Forty-four young top level football players divided equally into an experimental and a control group were submitted to two different training programmes for an 8-month period. Each group consisted of 5 forwards, 6 midfielders, 4 fullbacks, 4 centerbacks and 3 goalkeepers. The two groups had almost the same average age (17.8 +/- 0.6 and 17.7 +/- 0.6 yrs respectively), weight (72.6 +/- 4.7 and 72.8 +/- 3.7 kg) and height (181.3 +/- 4.4 and 180.3 +/- 4.0 cm). The following measurements were taken before and after the training period in order to evaluate the aerobic and anaerobic (lactacid and alactacid) power as well as explosive and elastic power which are related to football performance: running tests of 30, 50, 300 and 1,000 meters, squat jump (SJ), counter movement jump (CMJ) and repetition counter movement jump (test 15"). RESULTS: A percent improvement observed for forwards and centerbacks was significant, in comparison with the control group, in all tests but the 30 and 1,000 meters run, on the contrary fullbacks and midfielders demonstrated a significant improvement only in the 1000 m run test (p < 0.01). In addition, a significant increase (14%, p < 0.01) was observed in CMJ of goalkeepers in the experimental group, in comparison with the control group. CONCLUSIONS: It is concluded that individualized training developed in accordance with the real model of football performance and the different mechanisms of bioenergetic processes, is a superior method of training and can optimise the performance of all player in the team.


Assuntos
Metabolismo Energético , Futebol/fisiologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Educação Física e Treinamento
19.
Orthopedics ; 20(6): 505-9, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9195633

RESUMO

In the past 10 years, snowboarding has become a popular winter sport among young people, and the number of accidents has increased proportionately. The incidence of traumas from snowboarding is shown to be 4 to 6 for every 1000 medical examinations, which is similar to that of downhill skiing. However, other important statistical differences exist between the two sports. This study of 106 snowboarding-related injury cases analyzes the epidemiology of these injuries in Italy. Results found that 45.1% of injuries are located in the upper limbs and that significant advantages are obtained with the introduction of guards to protect the upper limbs during descent. Serious ligament injuries to the knee are more rare in snowboarding than in downhill skiing. In both sports, injuries are more common with rigid boots, which lead to a higher incidence of injury to the upper limbs. Finally, a high percentage of injury to beginners was found in this study. Training courses for those who are considering taking up the sport of snowboarding could significantly lower their risk of trauma.


Assuntos
Traumatismos em Atletas/epidemiologia , Esqui/lesões , Adolescente , Adulto , Traumatismos do Braço/epidemiologia , Traumatismos do Braço/etiologia , Traumatismos em Atletas/etiologia , Equipamentos e Provisões , Feminino , Humanos , Incidência , Itália/epidemiologia , Traumatismos da Perna/epidemiologia , Traumatismos da Perna/etiologia , Masculino , Aptidão Física , Neve
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA