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1.
Int Marit Health ; 75(2): 79-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38949220

RESUMO

BACKGROUND: In confined waters, ships run a high risk of groundings, contact, sinkings and near misses. In such waters the maritime traffic is dense, the waterway is narrow, the depth is limited, and tides and currents are constantly changing. MATERIALS AND METHODS: From 2009-2019, 75 accidents were investigated in the estuary of the Seine. Weather conditions and perceived fatigue were studied. From May to June 2020, 114 seafarers, 34 pilots and 80 captains, responded to a questionnaire focusing on the use of Pilot Portable Units (PPU) and Electronic Chart Display Information Systems (ECDIS). RESULTS: The 75 accidents corresponded to an average of 6.8 ± 3.2 accidents per year. Groundings were the most frequent accidents (35%, n = 26) followed by contact accidents with the quayside (25%, n = 19), between ships or tugs while manoeuvring (8%, n = 6) or while sailing (1%, n = 1). There was no loss of vessels nor fatalities of crew members. In poor weather conditions, there were 76% more accidents than in normal conditions (4.4 ± 2.5 accidents/10,000 movements versus 2.5 ± 1.9 accidents/10,000 movements, p < 0.03). Almost all the accidents (96%) were related to human errors of judgment (81%), or negligence (53%), or both (39). Perceived fatigue was probably in cause in 6 accidents. Only 3 accidents were related to mechanical causes. Through the questionnaires, 69% of the pilots complained of difficulties in mastering the devices and software. They felt distracted by alarms which affected their attention while navigating. They requested training on a simulator. Concerning ship captains, 83% felt comfortable with ECDIS devices yet only 20% were able to configure the ECDIS correctly. CONCLUSIONS: In the Seine estuary, 75 accidents occurred within the 11 year-study. Risk factors were poor weather conditions and human error. PPU and ECDIS were considered as useful tools in the prevention of accidents. However, pilots and captains requested more thorough training in their use.


Assuntos
Acidentes de Trabalho , Navios , Humanos , Acidentes de Trabalho/estatística & dados numéricos , França/epidemiologia , Adulto , Inquéritos e Questionários , Tempo (Meteorologia) , Masculino , Estuários , Pilotos/estatística & dados numéricos , Medicina Naval , Fadiga/epidemiologia , Feminino , Pessoa de Meia-Idade
2.
Int Marit Health ; 72(3): 155-162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604983

RESUMO

BACKGROUND: During cruises, the management of coronavirus disease 2019 (COVID-19) infections poses serious organizational problems such as those encountered in 2020 by the Zaandam, the aircraft carrier Charles de Gaulle or the Diamond Princess. In French Polynesia, the mixed cargo ship Aranui 5 transports both tourists and freight to the Marquesas Islands. The purpose of this article is to show how COVID-19 infections were diagnosed and contained before and after passengers boarded a cruise. MATERIALS AND METHODS: On October 15, 2020, 161 passengers including 80 crew members embarked for a 13-day voyage from Papeete to the Marquesas Islands. Prior to boarding, all passengers underwent a reverse transcriptase-polymerase chain reaction (RT-PCR) test; the tests results were all negative. On Day 0, 3, 5, 8 and 11, Biosynex® rapid antigen diagnostic tests were carried out on all or some of the crew members and tourists who may have had contact with new positive cases. Each day, forehead or temporal temperatures were measured using an infrared thermometer and questions were asked concerning the subjects' health status. When a subject was positive, the person and their contacts were isolated in individual cabins. The infected person then left the vessel to be received in a communal reception centre on the nearest island. RESULTS: A total of 9 positive cases were observed, including two before departure (a tourist and a crew member). During the trip, 7 crew members tested positive. The patients and their contacts were isolated and then disembarked at the earliest opportunity. At the time of sampling, the subjects were asymptomatic. The patients and their contacts all became symptomatic within 24 to 48 hours after sampling. CONCLUSIONS: In total, the voyage could be completed without any transmission on board among the tourists and with a minimum transmission among the crew members, thus maintaining the tourist and economic activity of the islands during the times of COVID-19 pandemic.


Assuntos
COVID-19/diagnóstico , COVID-19/prevenção & controle , Medicina Naval/métodos , Temperatura Corporal , COVID-19/epidemiologia , Teste para COVID-19 , Busca de Comunicante/métodos , Humanos , Exposição Ocupacional , Polinésia , Quarentena/métodos , SARS-CoV-2 , Navios , Viagem
3.
J Am Heart Assoc ; 9(9): e015017, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32336214

RESUMO

BACKGROUND In New Caledonia, a South Pacific archipelago whose inhabitants comprise Melanesians, Europeans/whites, Wallisians, Futunans, Polynesians, and Asians, the prevalence of rheumatic heart disease (RHD) is 0.9% to 1% at ages 9 and 10. It could be higher at the age of 16, but this remains to be verified. METHODS AND RESULTS A total of 1530 Melanesian, Métis, white, Wallisian, Futunan, Polynesian, and Asian adolescents benefited from a transthoracic echocardiogram. Definite or borderline RHD, nonrheumatic valve lesions, congenital heart defects, family and personal history of acute rheumatic fever, and socioeconomic factors were collected. The prevalence of cardiac abnormalities was 8.1%, made up of 4.1% RHD including 2.4% definite and 1.7% borderline RHD, 1.7% nonrheumatic valve lesions, and 2.3% congenital anomalies. In whites and Asians, there were no cases of RHD. RHD was higher in the Wallisian, Futunan, and Polynesian group (7.6%) when compared with Melanesians (5.3%) and Métis (2.9%). The number of nonrheumatic valve lesions was not statistically different in the different ethnicities. The prevalence of RHD was higher in adolescents with a personal history of acute rheumatic fever, in those living in overcrowded conditions, and in those whose parents were unemployed or had low-income occupations, such as the farmers or manual workers. CONCLUSIONS RHD was 4 times higher in adolescents at age 16 than at ages 9 and 10 (4.1% versus 0.9%-1%). No cases of RHD were observed in whites and Asians. The determining factors were history of acute rheumatic fever and socioeconomic factors.


Assuntos
Havaiano Nativo ou Outro Ilhéu do Pacífico , Cardiopatia Reumática/etnologia , Adolescente , Fatores Etários , Ecocardiografia Doppler em Cores , Feminino , Humanos , Masculino , Nova Caledônia/epidemiologia , Prevalência , Estudos Prospectivos , Fatores Raciais , Cardiopatia Reumática/diagnóstico por imagem , Medição de Risco , Fatores de Risco , Determinantes Sociais da Saúde , Fatores Socioeconômicos
4.
Int J Cardiol ; 278: 273-279, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30579721

RESUMO

BACKGROUND: Pre-participation cardiovascular evaluation (PPE) aims to detect cardiac disease with sudden cardiac death (SCD) risk. No study has focused on Pacific Island athletes. METHODS: A total of 2281 Pacific Island athletes were studied with (i) a questionnaire on family, personal history and symptoms, (ii) a physical examination and (iii) a 12-lead ECG. RESULTS: 85% presented a normal history and examination. A positive family history was 1.4-1.9 fold higher in Melanesians, Polynesians and Métis than in Caucasians, while a positive personal history, abnormal symptoms and abnormal examination was 1.3 fold higher in Melanesians and Métis than in others. Neither gender nor training level had a bearing on these results. Melanesians had higher T wave inversions (TWIs) in V2-V4 leads but had no CV abnormalities. Lateral or infero-lateral TWIs were found in 6 male and in 5 highly trained athletes and cardiomyopathies were diagnosed in 3/6 athletes. Overall, 3.9% athletes were found to have a CV abnormality and 0.8% had a risk of SCD. Polynesians and males were more at risk than the others while the level of training made no difference. In athletes at risk of SCD, the main detected CV diseases were cardiomyopathies, Wolff-Parkinson-White (WPW) and severe valve lesions of rheumatoid origin. CONCLUSIONS: PPE revealed that 3.9% presented CV abnormalities. A risk of SCD was found in 0.8% with cardiomyopathies, WPW, and severe valve lesions of rheumatoid origin. Melanesians, Polynesians and male of high level of training were more at risk than others.


Assuntos
Atletas , Doenças Cardiovasculares/etnologia , Morte Súbita Cardíaca/etnologia , Exercício Físico/fisiologia , Participação do Paciente/métodos , Adolescente , Adulto , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Criança , Eletrocardiografia/métodos , Feminino , Seguimentos , Humanos , Masculino , Ilhas do Pacífico/etnologia , Exame Físico/métodos , Adulto Jovem
5.
Int J Cardiol ; 257: 16-23, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29506688

RESUMO

BACKGROUND: The importance of exercise electrocardiogram (ECG) has been controversial in the prevention of cardiac events among sportsmen. The aim of this study was to determine the frequency of silent myocardial ischemia (SMI) from an exercise ECG and its relationship with induced coronary angiographic assessment and potentially preventable cardiac events. METHODS: This prospective cohort study included leisure time asymptomatic sportsmen over 35years old, referred from 2011 to 2014 in the Sports Medicine Unit of the University Hospital of Saint-Etienne. RESULTS: Of the cohort of 1500 sportsmen (1205 men; mean age 50.7±9.4years; physical activity level 32.8±26.8MET-h/week), 951 (63%) had at least one cardiovascular disease (CVD) risk factor. Family history, medical examination and standard resting 12-lead were collected. A total of 163 exercise ECGs (10.9%) were defined as positive, most of them due to SMI (n=129, 8.6%). SMI was an indication for coronary angiography in 23 cases, leading to 17 documented SMIs (1.1%), including 11 significant stenoses requiring revascularization. In multivariate logistic regression analysis, a high risk of CVD (OR=2.65 [CI 95%: 1.33-5.27], p=0.005) and an age >50years (OR=2.71 [CI 95%: 1.65-4.44], p<0.0001) were independently associated with confirmed SMI. CONCLUSIONS: The association of positive exercise ECG with significant coronary stenosis was stronger among sportsmen with CVD risk factors and older than 50years. Screening by exercise ECG can lower the risk of cardiac events in middle-aged and older sportsmen. One hundred tests would be enough to detect one silent myocardial ischemia at risk for cardiac event.


Assuntos
Eletrocardiografia/métodos , Teste de Esforço/métodos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Medicina Esportiva/métodos , Esportes/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Eletrocardiografia/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Esportes/tendências , Medicina Esportiva/tendências
6.
JMIR Res Protoc ; 6(4): e58, 2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28408363

RESUMO

BACKGROUND: Morbidity before retirement has a huge cost, burdening both public health and workplace finances. Multiple factors increase morbidity such as stress at work, sedentary behavior or low physical activity, and poor nutrition practices. Nowadays, the digital world offers infinite opportunities to interact with workers. The WittyFit software was designed to understand holistic issues of workers by promoting individualized behavior changes at the workplace. OBJECTIVE: The shorter term feasibility objective is to demonstrate that effective use of WittyFit will increase well-being and improve health-related behaviors. The mid-term objective is to demonstrate that WittyFit improves economic data of the companies such as productivity and benefits. The ultimate objective is to increase life expectancy of workers. METHODS: This is an exploratory interventional cohort study in an ecological situation. Three groups of participants will be purposefully sampled: employees, middle managers, and executive managers. Four levels of engagement are planned for employees: commencing with baseline health profiling from validated questionnaires; individualized feedback based on evidence-based medicine; support for behavioral change; and formal evaluation of changes in knowledge, practices, and health outcomes over time. Middle managers will also receive anonymous feedback on problems encountered by employees, and executive top managers will have indicators by division, location, department, age, seniority, gender and occupational position. Managers will be able to introduce specific initiatives in the workplace. WittyFit is based on two databases: behavioral data (WittyFit) and medical data (WittyFit Research). Statistical analyses will incorporate morbidity and well-being data. When a worker leaves a workplace, the company documents one of three major explanations: retirement, relocation to another company, or premature death. Therefore, WittyFit will have the ability to include mortality as an outcome. WittyFit will evolve with the waves of connected objects further increasing its data accuracy. Ethical approval was obtained from the ethics committee of the University Hospital of Clermont-Ferrand, France. RESULTS: WittyFit recruitment and enrollment started in January 2016. First publications are expected to be available at the beginning of 2017. CONCLUSIONS: The name WittyFit came from Witty and Fitness. The concept of WittyFit reflects the concept of health from the World Health Organization: being spiritually and physically healthy. WittyFit is a health-monitoring, health-promoting tool that may improve the health of workers and health of companies. WittyFit will evolve with the waves of connected objects further increasing its data accuracy with objective measures. WittyFit may constitute a powerful epidemiological database. Finally, the WittyFit concept may extend healthy living into the general population. TRIAL REGISTRATION: Clinicaltrials.gov: NCT02596737; https://www.clinicaltrials.gov/ct2/show/NCT02596737 (Archived by WebCite at http://www.webcitation.org/6pM5toQ7Y).

7.
Br J Sports Med ; 49(19): 1262-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26238869

RESUMO

BACKGROUND: The health benefits of 150 min a week of moderate-to-vigorous-intensity physical activity (MVPA) in older adults, as currently recommended, are well established, but the suggested dose in older adults is often not reached. OBJECTIVES: We aimed to determine whether a lower dose of MVPA was effective in reducing mortality, in participants older than 60 years. METHODS: The PubMed and Embase databases were searched from inception to February 2015. Only prospective cohorts were included. Risk ratios of death were established into four doses based on weekly Metabolic Equivalent of Task (MET)-minutes, defined as inactive (reference), low (1-499), medium (500-999) or high (≥1000). Data were pooled and analysed through a random effects model using comprehensive meta-analysis software. RESULTS: Of the 835 reports screened, nine cohort studies remained, totalling 122 417 participants, with a mean follow-up of 9.8±2.7 years and 18 122 reported deaths (14.8%). A low dose of MVPA resulted in a 22% reduction in mortality risk (RR=0.78 (95% CI 0.71 to 0.87) p<0.0001). MVPA beyond this threshold brought further benefits, reaching a 28% reduction in all-cause mortality in older adults who followed the current recommendations (RR=0.72 (95% CI 0.65 to 0.80) p<0.0001) and a 35% reduction beyond 1000 MET-min per week (RR=0.65 (95% CI 0.61 to 0.70) p<0.0001). CONCLUSIONS: A dose of MVPA below current recommendations reduced mortality by 22% in older adults. A further increase in physical activity dose improved these benefits in a linear fashion. Older adults should be encouraged to include even low doses of MVPA in their daily lives.


Assuntos
Exercício Físico/fisiologia , Mortalidade , Idoso , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
9.
J Strength Cond Res ; 24(8): 2026-31, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20634753

RESUMO

The accuracy of a simple field test, the 3-minute, 30-second endurance capacity test (3'30'' ECT), was evaluated in 12 moderately trained athletes. It consisted of 10 3-minute running bouts, separated by 30-second passive recoveries. The first 5 bouts were performed at 75% of maximal aerobic speed (MAS, which was previously determined), and the last 5 were at a self-selected speed. The result of this test is a speed called Vend, expressed in km.h and calculated as the mean speed for the last 5 bouts. The critical velocity (CV) and the individual anaerobic threshold (IAT) were also determined. Another 17 moderately trained athletes then participated in a test-retest procedure to assess the reproducibility of the 3'30'' ECT. The results showed that Vend was correlated with all studied parameters (p < 0.05). Vend and CV did not differ relative to MAS (Vend: 82.8 +/- 3.3% of MAS; CV 82.5 +/- 3.3% of MAS; p > 0.05). The test-retest procedure indicated a coefficient of variation of 1.99 +/- 1.88%. Vend is thus an interesting indicator because (a) it is based on a noninvasive single-visit protocol, (b) its application is in the heavy exercise domain, and (c) it is highly reproducible. The 3'30'' ECT thus seems to be an adequate test to determine endurance capacity in moderately trained subjects.


Assuntos
Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Frequência Cardíaca/fisiologia , Humanos , Lactatos/sangue , Masculino , Esforço Físico/fisiologia
10.
J Sports Sci Med ; 8(2): 190-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-24149525

RESUMO

We examined the leptin response and related hormones during and after two sub-maximal exercise protocols in trained and untrained subjects. During this study, plasma concentrations of leptin [Lep], insulin [I], cortisol [C], growth hormone [GH], glucose [G] and lactate [La] were measured. 7 elite volleyball trained players (TR) and 7 untrained (UTR) subjects (percent body fat: 13.2 ± 1.8 versus 15.7 ± 1.0, p < 0.01, respectively) were examined after short and prolonged sub-maximal cycling exercise protocols (SP and PP). Venous blood samples were collected before each protocol, during, at the end, and after 2 and 24 h of recovery. SP and PP energy expenditures ranged from 470 ± 60 to 740 ± 90 kcal for TR and from 450 ± 60 to 710 ± 90 kcal for UTR, respectively. [Lep] was related to body fat percentage and body fat mass in TR (r = 0. 84, p < 0.05 and r = 0.93, p < 0.01) and in UTR (r = 0.89, p < 0.01 and r = 0.92, p < 0. 01, respectively). [Lep] did not change significantly during both protocols for both groups but was lower (p < 0.05) in all sampling in TR when compared to UTR. Plasma [I] decreased (p < 0.01) and [GH] increased (p < 0.01) significantly during both SP and PP and these hormones remained lower (I: p < 0.01) and higher (GH: p < 0.01) than pre-exercise levels after a 2-h recovery period, returning to base-line at 24-h recovery. Plasma [La] increased (p < 0.01) during both protocols for TR and UTR. There was no significant change in [C] and [G] during and after both protocols for all subjects. It is concluded that 1) leptin is not sensitive to acute short or prolonged sub-maximal exercises (with energy expenditure under 800 kcal) in volleyball/ anaerobically trained athletes as in untrained subjects, 2) volleyball athletes showed significantly lower resting and exercise leptin response with respect to untrained subjects and 3) it appears that in these anaerobically trained athletes leptin response to exercise is more sensitive to the level of energy expenditure than hormonal or metabolic modifications induced by acute exercise. Key pointsTrials concerning acute exercise and leptin indicated discrepant results.Acute exercise with energy expenditure higher than 800 kcal can decrease leptinemia.Elite volleyball players presented decreased leptin levels than untrained subjects.

11.
Med Sci Sports Exerc ; 40(6): 1149-54, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18460989

RESUMO

PURPOSE: To investigate the effect of fastskin suits on 25- to 800-m performances, drag, and energy cost of swimming. METHODS: The performances, stroke rate and distance per stroke, were measured for 14 competitive swimmers in a 25-m pool, when wearing a normal suit (N) and when wearing a full-body suit (FB) or a waist-to-ankle suit (L). Passive drag, oxygen uptake, blood lactate, and the perceived exertion were measured in a flume. RESULTS: There was a 3.2% +/- 2.4% performance benefit for all subjects over the six distances covered at maximal speed wearing FB and L when compared with N. When wearing L, the gain was significantly lower (1.8% +/- 2.5%, P < 0.01) than when wearing FB compared with N. The exercise perception was significantly lower when wearing FB than N, whereas there was no statistical difference when wearing L. The distance per stroke was significantly higher when wearing FB and L, whereas the differences in stroke rate were not statistically significant. There was a significant reduction in drag when wearing FB and L of 6.2% +/- 7.9% and 4.7% +/- 4.4%, respectively (P < 0.01), whereas the energy cost of swimming was significantly reduced when wearing FB and L by 4.5% +/- 5.4% and 5.5% +/- 3.1%, respectively (P < 0.01). However, the differences between FB and L were not statistically significant for drag and oxygen uptake. CONCLUSION: FB and L significantly reduced passive drag, and this was associated with a decreased energy cost of submaximal swimming and an increased distance per stroke, at the same stroke rates, and reduced freestyle performance time.


Assuntos
Desempenho Atlético/fisiologia , Metabolismo Energético/fisiologia , Equipamentos Esportivos , Natação/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Med Sci Sports Exerc ; 39(10): 1784-93, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17909406

RESUMO

PURPOSE: This study analyzed kinematic changes during a 100-m front crawl to investigate the effects of performance level and gender, comparing 12 high-speed males, 8 medium-speed males, 8 low-speed males, and 8 high-speed females. METHODS: Assessments were made throughout the race in a 25-m pool divided into five zones of 5 m. Velocity (V), stroke rate (SR), and stroke length (SL) were calculated for each 25-m length (L1 to L4) and for each 5-m zone. Four stroke phases were identified by video analysis, and the index of coordination (IdC) was calculated. Three modes of arm coordination were identified: catch-up, opposition, and superposition. The leg kick was also analyzed. RESULTS: The high-speed male swimmers were distinguished by higher V (1.89 m.s(-1)), SR (0.78 Hz), SL (2.16 m per stroke), propulsive phase (54%), and IdC (3.8%) (P < 0.05), and by the stability of these values throughout the race. The medium- and low-speed males had an opposition coordination (-1% < IdC < 1%) during the third length of the 100 m. Because of fatigue in length 4, they spent more time with the hand in the push phase (possibly because of a decrease in hand velocity) and changed to superposition coordination (medium-speed males: IdC = 2.78%; low-speed males: IdC = 1.12%) (P < 0.05). This change was ineffective, however, as SL continued to decrease throughout the 100 m (P < 0.05). The main gender findings were the greater SL of the males versus the females (1.81 m per stroke) (P < 0.05) and the similar IdC of both high-speed groups (females: 4.4%). CONCLUSION: The high-speed swimmers were characterized by higher and more stable SL and IdC. The principal gender effect was greater SL in the males than in the females.


Assuntos
Comportamento Competitivo/fisiologia , Desempenho Psicomotor/fisiologia , Natação/fisiologia , Adolescente , Adulto , Braço , Fenômenos Biomecânicos , Feminino , França , Lateralidade Funcional/fisiologia , Humanos , Perna (Membro) , Masculino , Fatores Sexuais , Análise e Desempenho de Tarefas
13.
J Strength Cond Res ; 21(2): 431-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17530954

RESUMO

The present study investigated the influence of a 12-week electromyostimulation (EMS) training program performed by elite rugby players. Twenty-five rugby players participated in the study, 15 in an electrostimulated group and the remaining 10 in a control group. EMS was conducted on the knee extensor, plantar flexor, and gluteus muscles. During the first 6 weeks, training sessions were carried out 3 times a week and during the last 6 weeks, once a week. Isokinetic torque of the knee extensors was determined at different eccentric and concentric angular velocities ranging from -120 to 360 degrees .s(-1). Scrummaging and full squat strength, vertical jump height and sprint-running times were also evaluated. After the first 6 weeks of EMS, only the squat strength was significantly improved (+8.3 +/- 6.5%; p < 0.01). After the 12th week, the -120 degrees .s(-1) maximal eccentric, 120 and 240 degrees .s(-1) maximal concentric torque (p < 0.05), squat strength (+15.0 +/- 8.0%; p < 0.001), squat jump (+10.0 +/- 9.5%; p < 0.01), and drop jump from a 40-cm height (+6.6 +/- 6.1%; p < 0.05) were significantly improved. No significant change was observed for the control group. A 12-week EMS training program demonstrated beneficial effects on muscle strength and power in elite rugby players on particular tests. However, rugby skills such as scrummaging and sprinting were not enhanced.


Assuntos
Estimulação Elétrica/métodos , Futebol Americano/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Educação Física e Treinamento/métodos , Adaptação Fisiológica/fisiologia , Adulto , Análise de Variância , Humanos , Masculino , Análise e Desempenho de Tarefas , Torque
14.
J Strength Cond Res ; 21(2): 599-605, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17530963

RESUMO

This study was undertaken to compare the effects of dry-land strength training with a combined in-water resisted- and assisted-sprint program in swimmer athletes. Twenty-one swimmers from regional to national level participated in this study. They were randomly assigned to 3 groups: the strength (S) group that was involved in a dry-land strength training program where barbells were used, the resisted- and assisted-sprint (RAS) group that got involved in a specific water training program where elastic tubes were used to generate resistance and assistance while swimming, and the control (C) group which was involved in an aerobic cycling program. During 12 weeks, the athletes performed 6 training sessions per week on separate days. All of them combined the same aerobic dominant work for their basic training in swimming and running with their specific training. Athletes were evaluated 3 times: before the training program started, after 6 weeks of training, and at the end of the training program. The outcome values were the strength of the elbow flexors and extensors evaluated using an isokinetic dynamometer, and the speed, stroke rate, stroke length, and stroke depth observed during a 50-meter sprint. No changes were observed after 6 weeks of training. At the end of the training period, we observed significant increases in swimming velocity, and strength of elbow flexors and extensors both in the S and RAS groups. However, stroke depth decreased both in the S and RAS groups. Stroke rate increased in the RAS but not in the S group. However, no significant differences in the swimming performances between the S and RAS groups were observed. No significant changes occurred in C. Altogether, programs combining swimming with dry-land strength or with in-water resisted- and assisted-sprint exercises led to a similar gain in sprint performance and are more efficient than traditional swimming training methods alone.


Assuntos
Educação Física e Treinamento/métodos , Natação/fisiologia , Adaptação Fisiológica , Adolescente , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Dinamômetro de Força Muscular
15.
J Strength Cond Res ; 20(3): 547-54, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16937967

RESUMO

This study was undertaken to determine whether the resisted-sprint in overstrength (OSt) or the assisted-sprint in overspeed (OSp) could be efficient training methods to increase 100-m front crawl performance. Thirty-seven (16 men, 21 women) competition-level swimmers (mean +/- SD: age 17.5 +/- 3.5 years, height 173 +/- 14 cm, weight 63 +/- 14 kg) were randomly divided into 3 groups: OSt, OSp, and control (C). All swimmers trained 6 days per week for 3 weeks, including 3 resisted or assisted training sessions per week for the groups OSt and OSp respectively. Elastic tubes were used to generate swimming overstrength and overspeed. Three 100-m events were performed before, during, and after the training period. Before each 100-m event, strength of the elbow flexors and extensors was measured with an isokinetic dynamometer. Stroke rate and stroke length were evaluated using the video-recorded 100-m events. In the OSt group, elbow extensor strength, swimming velocity, and stroke rate significantly increased (p < 0.05), while stroke length remained unchanged after the 3-week training period. In the OSp group, stroke rate significantly increased (p < 0.05) and stroke length significantly decreased (p < 0.05) without changes in swimming velocity. No significant variations in the C group were observed. Both OSt and OSp proved to be more efficient than the traditional training program. However, the OSt training program had a larger impact on muscle strength, swimming performance, and stroke technique than the OSp program.


Assuntos
Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Natação/fisiologia , Adaptação Fisiológica , Adolescente , Feminino , Humanos , Masculino , Contração Muscular/fisiologia , Dinamômetro de Força Muscular , Fatores Sexuais , Extremidade Superior/fisiologia
16.
J Sports Sci ; 24(5): 509-20, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16608765

RESUMO

The aim of this study was to carry out a statistical analysis of the Banister model to verify how useful it is in monitoring the training programmes of elite swimmers. The accuracy, the ill-conditioning and the stability of this model were thus investigated. The training loads of nine elite swimmers, measured over one season, were related to performances with the Banister model. First, to assess accuracy, the 95% bootstrap confidence interval (95% CI) of parameter estimates and modelled performances were calculated. Second, to study ill-conditioning, the correlation matrix of parameter estimates was computed. Finally, to analyse stability, iterative computation was performed with the same data but minus one performance, chosen at random. Performances were related to training loads for all participants (R(2) = 0.79 +/- 0.13, P < 0.05) and the estimation procedure seemed to be stable. Nevertheless, the range of 95% CI values of the most useful parameters for monitoring training was wide: t(a) = 38 (17, 59), t(f) = 19 (6, 32), t(n) = 19 (7, 35), t(g) = 43 (25, 61). Furthermore, some parameters were highly correlated, making their interpretation worthless. We suggest possible ways to deal with these problems and review alternative methods to model the training-performance relationships.


Assuntos
Modelos Biológicos , Educação Física e Treinamento , Aptidão Física/fisiologia , Natação/fisiologia , Adulto , Feminino , Humanos , Masculino , Educação Física e Treinamento/métodos , Descanso/fisiologia , Análise e Desempenho de Tarefas
17.
Med Sci Sports Exerc ; 37(3): 455-60, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15741845

RESUMO

PURPOSE: The aim of this study was to examine the influence of a short-term electromyostimulation (EMS) training program on the strength of knee extensors, skating, and vertical jump performance of a group of ice hockey players. METHODS: Seventeen ice hockey players participated in this study, with nine in the electrostimulated group (ES) and the remaining height as controls (C). EMS sessions consisted of 30 contractions (4-s duration, 85 Hz) and were carried out 3x wk for 3 wk. Isokinetic strength of the knee extensor muscles was determined with a Biodex dynamometer at different eccentric and concentric angular velocities (angular velocities ranging from -120 to 300 degrees .s). Jumping ability was evaluated during squat jump (SJ), countermovement jump (CMJ), drop jump (DJ), and 15 consecutive CMJ (15J). Sprint times for 10- and 30-m skates in specific conditions were measured using an infrared photoelectric system. RESULTS: After 3 wk of EMS training, isokinetic torque increased significantly (P<0.05) for ES group in eccentric (-120 and -60 degrees .s) and concentric conditions (60 and 300 degrees .s), whereas vertical jump height decreased significantly (P<0.05) for SJ (-2.9+/-2.4 cm), CMJ (-2.1+/-2.0 cm), and DJ (-1.3+/-1.1 cm). The 10-m skating performance was significantly improved (from 2.18+/-0.20 to 2.07+/-0.09 s, before and after the 3-wk EMS period, respectively; P<0.05). CONCLUSION: It was demonstrated that an EMS program of the knee extensors significantly enhanced isokinetic strength (eccentric and for two concentric velocities) and short skating performance of a group of ice hockey players.


Assuntos
Estimulação Elétrica/métodos , Hóquei/fisiologia , Músculo Esquelético/fisiologia , Educação Física e Treinamento/métodos , Análise e Desempenho de Tarefas , Adaptação Fisiológica/fisiologia , Adulto , Humanos , Torque
18.
J Strength Cond Res ; 19(1): 67-75, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15705048

RESUMO

The aim of this study was to model the residual effects of training on the swimming performance and to compare a model that includes threshold saturation (MM) with the Banister model (BM). Seven Olympic swimmers were studied over a period of 4 +/- 2 years. For 3 training loads (low-intensity w(LIT), high-intensity w(HIT), and strength training w(ST)), 3 residual training effects were determined: short-term (STE) during the taper phase (i.e., 3 weeks before the performance [weeks 0, 1, and 2]), intermediate-term (ITE) during the intensity phase (weeks 3, 4, and 5), and long-term (LTE) during the volume phase (weeks 6, 7, and 8). ITE and LTE were positive for w(HIT) and w(LIT), respectively (p < 0.05). Low-intensity training load during taper was related to performances by a parabolic relationship (p < 0.05). Different quality measures indicated that MM compares favorably with BM. Identifying individual training thresholds may help individualize the distribution of training loads.


Assuntos
Modelos Biológicos , Educação Física e Treinamento/métodos , Resistência Física/fisiologia , Natação/fisiologia , Adulto , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Análise de Regressão
20.
Med Sci Sports Exerc ; 36(2): 218-24, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14767243

RESUMO

PURPOSE: The effect of training variations on 24-h urinary cortisol/cortisone (C/Cn) ratio was investigated in highly trained swimmers to determine whether it could be a good marker of training stress and performance. METHODS: Fourteen swimmers (five female and nine male) were tested after 4 wk of intense training (IT), 3 wk of reduced training (RT), and 5 wk of moderate training (MT). At the end of each period, the swimmers performed in their best event at an official competition. Individual performances were expressed as a percentage of the previous season's best performance. The fatigue state was evaluated with a questionnaire. RESULTS: The C/Cn ratio was statistically different for the three periods (IT: 1.10 +/- 0.7, RT: 0.64 +/- 0.3, and MT: 0.57 +/- 0.2). The differences in the C/Cn ratio between two consecutive performances were related to the differences in performance (r = -0.52, P < 0.01), and the C/Cn ratio was significantly related to the total training (r = 0.32, P < 0.05) and total score of fatigue (TSF) (r = 0.35, P < 0.03) over the follow-up period. Cn levels were related to the dryland training (r = -0.46; P < 0.01) and TSF (r = -0.40; P < 0.02). During IT, variations in the C/Cn ratio were related to the changes in the mean intensity (r = -0.67; P < 0.02) and to TSF (r = 0.69; P < 0.01). CONCLUSION: The 24-h C/Cn ratio was moderately related to both training and performance whereas Cn levels were only related to training. The C/Cn ratio could be a useful indicator for monitoring the overreaching state in elite swimmers.


Assuntos
Cortisona/urina , Hidrocortisona/urina , Educação Física e Treinamento/métodos , Medicina Esportiva/métodos , Natação/fisiologia , Adulto , Biomarcadores/urina , Fadiga/urina , Feminino , Humanos , Masculino , Estresse Fisiológico/urina , Análise e Desempenho de Tarefas
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