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1.
Ann Vasc Surg ; 70: 213-218, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32333951

RESUMO

BACKGROUND: Symptomatic peripheral artery disease of the lower extremity rarely affects young adults and, when present, typically has a nonatherosclerotic etiology. Anatomical variants have manifested as symptomatic foot ischemia in four cases in the literature. We describe the case of a 17-year-old girl presenting with foot pain upon plantar flexion due to dynamic dorsalis pedis (DP) artery entrapment by fibrous bands and the extensor hallucis brevis (EHB) tendon. METHODS: The patient was a 17-year-old girl who presented with right foot pain upon plantar flexion, which resolved upon returning to the neutral position. The potential site of compression was identified on MRI where the DP artery ran deep to the EHB tendon near the first and second tarsometatarsal joints. On diagnostic arteriogram, there was notching of the dorsalis pedis over the talus bone. The dorsalis pedis Doppler signal was obliterated upon plantar flexion. A longitudinal incision was made over the artery in the area of compression. The flexor retinaculum was incised. Abnormal fibrous bands were identified, which were lysed anterior to the artery. The EHB tendon was released and transferred distally to the extensor hallucis longus tendon. RESULTS: A completion angiogram showed a persistently patent dorsalis pedis artery with plantar flexion. She was discharged one day postoperatively without issues. On follow-up, the patient was ambulatory with complete resolution of her pain. Arterial duplex demonstrated normal velocities through the dorsalis pedis in all positions. CONCLUSIONS: Symptomatic peripheral artery disease is a rare presentation in young adults and is usually due to nonatherosclerotic pathophysiology. We present a rare case of dorsalis pedis artery entrapment syndrome. Given the mechanical nature of obstruction, surgical correction was an effective treatment.


Assuntos
Pé/irrigação sanguínea , Claudicação Intermitente/etiologia , Doença Arterial Periférica/etiologia , Corrida , Tendões/fisiopatologia , Adolescente , Fenômenos Biomecânicos , Descompressão Cirúrgica , Feminino , Humanos , Claudicação Intermitente/diagnóstico por imagem , Claudicação Intermitente/fisiopatologia , Claudicação Intermitente/cirurgia , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Doença Arterial Periférica/cirurgia , Resistência Física , Recuperação de Função Fisiológica , Transferência Tendinosa , Tendões/diagnóstico por imagem , Tendões/cirurgia , Tenotomia , Resultado do Tratamento
2.
Artigo em Inglês | MEDLINE | ID: mdl-33167485

RESUMO

This study determined the strength training (ST) habits of amateur endurance runners in Spain regarding athletic level. A sixteen-item online questionnaire comprised of (i) demographic information, (ii) performance, and (iii) training contents was completed by 1179 athletes. Five group levels were determined according to the personal best times of the athletes in a 10-km trial (LG1: level group 1, 50-55 min; LG2: level group 2, 45-50 min; LG3: level group 3, 40-45 min; LG4: level group 4, 35-40 min; LG5: level group 5, 30-35 min). Most athletes (n = 735, 62.3%) perceived ST as being a key component in their training program. Resistance training (RT) was reported as a ST type used by 63.4% of the athletes, 66.9% reported using bodyweight exercises, 46.8% reported using plyometric training, 65.6% reported using uphill runs, and 17.8% reported using resisted runs. The prevalence of runners who excluded ST from their training programs decreased as the athletic performance level increased (18.2% in lower-level athletes vs. 3.0% in higher-level), while the inclusion of RT, bodyweight exercises, plyometric training, and uphill and resisted runs was more frequent within higher-level groups. Most athletes included ST using low-to-moderate loads and high a number of repetitions/sets comprised of RT, plyometric training, resisted runs, and core, respiratory, and foot muscles training.


Assuntos
Exercício Pliométrico , Treinamento de Resistência , Corrida , Atletas , Hábitos , Humanos , Força Muscular , Resistência Física , Espanha
3.
Artigo em Inglês | MEDLINE | ID: mdl-33143006

RESUMO

This study evaluates the anatomical profiles, jump, sprint, power outputs, endurance, and peak blood lactate levels ([LA]peak) of handball players of two age groups-U17 (n = 77) and U19 (n = 46)-and analyses the role of training in their physical abilities. Vertical jump performance was determined by counter movement jump (CMJ) and counter movement jump with free arms (CMJFA) tests. A running-based anaerobic sprint test (RAST) determined the relative power output (watts/kg body weight) and absolute power output (watts) of the players. Sprint performance over 5 m, 10 m, and 30 m distances was evaluated. An incremental shuttle run test (40 m) was designed to determine aerobic threshold (AeT), anaerobic threshold (AnT), and [LA]peak. All parameters were measured for pivots, wingers, backs, and goalkeepers of each group. The U19 players were significantly heavier than the U17 group, but both the groups were nearly equal in height. The U19 group jumped higher than the U17 members, although the only significant difference (p = 0.032) was observed between the wingers of the groups in CMJ. Sprint performance varied marginally between the groups and only U19 pivots were found to be significantly (for distances of 5, 10, and 30 m: p = 0.047, p = 0.018, and p = 0.021, respectively) faster than U17 pivots. No difference in relative power output between the groups was noted, although the U19 players recorded higher absolute power outputs. Maximal velocity and velocities at the AeT and AnT were almost similar in the groups. Distance covered by the groups at the intensities of AeT and AnT varied only little. Higher [LA]peak was observed in the U19 players. U19 players failed to convert their superior power into speed and jump. The training pattern of the handball players needs to be revised so that U19 players may develop faster and be more enduring than the U17 group.


Assuntos
Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Resistência Física/fisiologia , Corrida/fisiologia , Adolescente , Limiar Anaeróbio , Feminino , Humanos , Ácido Láctico/sangue , Masculino , Movimento , Instituições Acadêmicas
4.
PLoS One ; 15(11): e0242439, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33186393

RESUMO

Sprint-interval training (SIT) is efficient at improving maximal aerobic capacity and anaerobic fitness at sea-level and may be a feasible training strategy at altitude. Here, it was evaluated if SIT intensity can be maintained in mild to moderate hypoxia. It was hypothesized that 6 x 30 s Wingate sprint performance with 2 min active rest between sprints can be performed in hypoxic conditions corresponding to ~3,000 m of altitude without reducing mean power output (MPO). In a single-blinded, randomized crossover design, ten highly-trained male endurance athletes with a maximal oxygen uptake ([Formula: see text]O2max) of 68 ± 5 mL O2 × min-1 × kg-1 completed 6 x 30 s all-out Wingate cycling sprints separated by two-minute active recovery on four separate days in a hypobaric chamber. The ambient pressure within the chamber on each experimental day was 772 mmHg (~0 m), 679 mmHg (~915 m), 585 mmHg (~ 2,150 m), and 522 mmHg (~3,050 m), respectively. MPO was not different at sea-level and up to ~2,150 m (~1% and ~3% non-significant decrements at ~915 and ~2,150 m, respectively), whereas MPO was ~5% lower (P<0.05) at ~3,050 m. Temporal differences between altitudes was not different for peak power output (PPO), despite a main effect of altitude. In conclusion, repeated Wingate exercise can be completed by highly-trained athletes at altitudes up to ~2,150 m without compromising MPO or PPO. In contrast, MPO was compromised in hypobaric hypoxia corresponding to ~3,050 m. Thus, SIT may be an efficient strategy for athletes sojourning to moderate altitude and aiming to maintain training quality.


Assuntos
Tolerância ao Exercício/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Consumo de Oxigênio/fisiologia , Adulto , Altitude , Atletas , Estudos Cross-Over , Exercício Físico/fisiologia , Humanos , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Masculino , Condicionamento Físico Humano/métodos , Resistência Física/fisiologia , Aptidão Física/fisiologia , Distribuição Aleatória , Corrida/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-33143175

RESUMO

This review aimed to synthesize evidence regarding interventions based on heart rate variability (HRV)-guided training for VO2max improvements in endurance athletes and address the issues that impact this performance enhancement. The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL Complete, the Web of Science Core Collection, Global Health, Current Contents Connect, and the SciELO citation index were searched. Inclusion criteria were: randomized controlled trials; studies with trained athletes enrolled in any regular endurance training; studies that recruited men, women, and both sexes combined; studies on endurance training controlled by HRV; studies that measured performance with VO2max. A random-effects meta-analysis calculating the effect size (ES) was used. Moderator analyses (according to the athlete's level and gender) and metaregression (according to the number of participants in each group) were undertaken to examine differences in ES. HRV-guided training and control training enhanced the athletes' VO2max (p < 0.0001), but the ES for the HRV-guided training group was significantly higher (p < 0.0001; ESHRVG-CG = 0.187). The amateur level and female subgroup reported better and significant results (p < 0.0001) for VO2max. HRV-guided training had a small (ES = 0.402) but positive effect on endurance athlete performance (VO2max), conditioned by the athlete's level and sex.


Assuntos
Desempenho Atlético , Treinamento Intervalado de Alta Intensidade , Consumo de Oxigênio , Resistência Física , Atletas , Feminino , Frequência Cardíaca , Humanos , Masculino
6.
Artigo em Inglês | MEDLINE | ID: mdl-33076438

RESUMO

A challenge for law enforcement agencies is the many positions that need filling. Agencies may modify their applicant test battery (ATB; multilevelled testing including fitness, background checks, psychological evaluations) to increase the hiring pool of potential recruits by augmenting the utility of testing. This study determined fitness differences of law enforcement recruits hired under two different ATB protocols. Retrospective analysis was conducted on seven academy classes (442 males, 84 females) hired under an older ATB, and one class (45 males, 13 females) hired under a newer ATB. Recruits completed the following before academy: 60 s push-ups and sit-ups (muscular endurance); vertical jump (lower-body power); medicine ball throw (upper-body power); 75 yard pursuit run (75PR; change-of-direction speed); and 20 m multistage fitness test (20MSFT; aerobic fitness). Independent sample t-tests (p ≤ 0.001) and effect sizes (d) evaluated between-group fitness differences for recruits hired under the different ATB protocols (combined sexes, males, and females). There were no significant differences between the ATB groups. However, newer ATB female recruits completed 13% fewer 20MSFT shuttles than the older ATB group, which, although not significant (p = 0.007), did have a moderate effect (d = 0.62). Females hired under the newer ATB had lower aerobic fitness, which could impact physical training performance and graduation.


Assuntos
Teste de Esforço , Aplicação da Lei , Aptidão Física , Adulto , Feminino , Humanos , Masculino , Resistência Física , Polícia , Estudos Retrospectivos , Adulto Jovem
7.
Arq. bras. cardiol ; 115(3): 468-477, out. 2020. tab, graf
Artigo em Português | LILACS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1131324

RESUMO

Resumo Fundamento Os dados mais utilizados como referência de aptidão cardiorrespiratória (ACR) são os de Cooper, que utiliza valores calculados de captação máxima de oxigênio (VO2máx). Objetivo Desenvolver valores de ACR a partir do teste cardiopulmonar de exercício (TCPE) em uma população brasileira com alto nível socioeconômico e livre de cardiopatia estrutural. Os resultados dos testes de VO2max foram comparados aos dados de Cooper e do FRIEND Registry. Métodos Foram utilizados neste estudo dados de TCPE de indivíduos consecutivos entre 1º de janeiro de 2000 e 31 de maio de 2016. Os critérios de inclusão foram: VO2máx pré-definido. Foi construído um gráfico de ACR de acordo com os percentuais do VO2máx: muito ruim (≤20%), ruim (20-40%), regular (40-60%), boa (60-80%), excelente (80-90%), e superior (≥90%). A correlação Kappa foi usada para analisar nossos dados em comparação aos dados dos outros dois bancos de dados. Os testes estatísticos com p<0,005 foram considerados significativos. Resultados A coorte final incluiu 18.186 testes: 12.552 homens, 5.634 mulheres (7 a 84 anos). A resposta mais recorrente foi "boa" (20,2%). Houve diferença média de peso, altura, índice de massa corporal (IMC) e idade no gráfico da ACR. Houve correlação inversa entre VO2máx e idade, peso e IMC. Usando uma regressão linear e essas variáveis, uma equação preditiva foi desenvolvida para o VO2máx. Nossas descobertas diferiram das dos outros bancos de dados. Conclusão Desenvolvemos uma classificação para a ACR e encontramos valores mais altos em todas as faixas de classificação de capacidade funcional, em contraste com os dados de Cooper e do FRIEND Registry. Nossos achados oferecem uma interpretação mais precisa da ACR nessa grande amostra populacional brasileira, quando comparados aos padrões anteriores, com base no VO2máx estimado. (Arq Bras Cardiol. 2020; 115(3):468-477)


Abstract Background The most widely used data for cardiorespiratory fitness (CRF) referrals are from the Cooper Clinic, which uses calculated maximal oxygen uptake (VO2max) values. Objective To develop CRF values from cardiopulmonary exercise testing (CPX) in a Brazilian population with high socioeconomic level and free of structural heart disease. VO2max testing results were compared with the Cooper Clinic and FRIEND Registry data. Methods CPX data from consecutive individuals between January 1,2000, and May 31,2016 were used in this study. Inclusion criteria were: VO2max by a pre-specified definition. We built a CRF chart according to VO2max percentiles: very poor (≤20%), poor (20-40%), fair (40-60%), good (60-80%), excellent (80-90%), and superior (≥90%). Kappa correlation was used to analyze our data in comparison with that of the other two databases. Statistical tests with p<0.005 were considered significant. Results Final cohort included 18,186 tests: 12,552 men, 5,634 women (7-84 years). The most recurrent response was "good" (20.2%). There was a mean difference in weight, height, body mass index (BMI), and age in the CRF chart. An inverse correlation existed between VO2max and age, weight, and BMI. Using a linear regression and these variables, a predictive equation was developed for VO2max. Our findings differed from that of the other databases. Conclusion We developed a classification for CRF and found higher values in all classification ranges of functional capacity in contrast to the Cooper Clinic and FRIEND Registry. Our findings offer a more accurate interpretation of ACR in this large Brazilian population sample when compared to previous standards based on the estimated VO2max. (Arq Bras Cardiol. 2020; 115(3):468-477)


Assuntos
Exercício Físico , Aptidão Física , Resistência Física , Estilo de Vida Saudável , Treino Aeróbico , Atividade Motora
8.
Internist (Berl) ; 61(11): 1140-1150, 2020 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-33025125

RESUMO

BACKGROUND: Malignant diseases lead to a decline in physical performance in a large number of patients. This includes a reduction of the musculoskeletal system, restrictions in cardiovascular fitness and psychogenically influenced syndromes such as fatigue and asthenia. It is not yet clear to what extent physical training can counteract these limitations or undesirable side effects and how this training needs to be designed in the individual situation. AIM OF THIS ARTICLE: The aim of this article is to find out whether physical training can be performed in cancer patients, how this training should be designed and which physical disorders can be influenced favorably. MATERIALS AND METHODS: In this review, the currently available work on this topic was evaluated and classified with regard to its feasibility and effects in cancer patients. RESULTS AND DISCUSSION: Physical training can be performed without complications in most patients even under treatment for the underlying malignant disease. It has a positive effect on physical performance, cardiovascular function, the perception of one's own cancer and overall well-being. Ideally, physical training for cancer patients should include a mixture of strength and endurance training. It should be carried out regularly and its intensity should be slowly increased. The type of physical activity should be adapted to the individual needs of the patient, take into account the particularities of the malignant disease and exclude any risk to the patient. CONCLUSION: In summary, a physical training program to accompany cancer therapy should be offered to virtually all patients with malignant disease.


Assuntos
Antineoplásicos/efeitos adversos , Exercício Físico , Neoplasias/tratamento farmacológico , Aptidão Física , Esportes , Antineoplásicos/uso terapêutico , Sistema Cardiovascular , Humanos , Oncologia , Neoplasias/psicologia , Resistência Física/fisiologia , Qualidade de Vida
9.
Artigo em Inglês | MEDLINE | ID: mdl-33003530

RESUMO

There is limited research examining the physical tasks that Brazilian special policemen groups can perform in the line of duty. The aims of this study were to (a) identify the occupational tasks of specialist police personnel serving in the Rapid Response Group (GRR) and Tactical Operations Command (COT), and to profile the frequency, difficulty, and importance of these tasks, and (b) to explore the current physical training these special operations police units (SOPUs) officers undertake to maintain their operational fitness. Univariate analysis for numerical variables (mean and standard deviation (SD)), as well as the absolute and relative frequencies for categorical variables were performed. Two Brazilian SOPUs performed a questionnaire with demographic, performance, and physical training sections. A total of 78 respondents (24 of the GRR and 54 of the COT) completed the survey. "Standing and/or sitting with complete equipment for long periods in different climatic conditions", and "lifting/pushing/pulling heavier objects" were the most frequent and difficult occupational tasks of both SOPUs, respectively. "Shooting a long weapon" and "breaking a door" were the most important for GRR and COT, respectively. All officers undertook regular physical training (~9 h/week), in an unstructured manner, without supervision, and planning of physical training is carried out autonomously (COT) or a mixture of autonomously and directed (GRR), with the main objectives of developing aerobic endurance and muscle strength. It is important that SOPUs teams train their members' physical capabilities to perform the tasks identified in this study, as well as follow a structured, supervised, and planned physical training program.


Assuntos
Condicionamento Físico Humano , Educação Física e Treinamento/estatística & dados numéricos , Resistência Física , Aptidão Física , Polícia/estatística & dados numéricos , Adulto , Brasil , Estudos Transversais , Humanos , Internet , Autorrelato
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(9): 1433-1439, 2020 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-33076594

RESUMO

Objective: To analyze the association between the endurance quality and blood pressure levels in Han students aged 13-18 years in China. Methods: We used the data of Han students aged 13-18 years from 2014 Chinese National Survey on Students' Constitution and Health. Elevated blood pressure and its components, including isolated elevated SBP, isolated elevated DBP, and mix elevated blood pressure, were evaluated according to the reference of screening for elevated blood pressure among children and adolescents aged 7-18 years. The students' endurance quality was scored according to the National Standards for Students' Physical Health (2014 revision) and categorized based on their percentiles into four groups as follows: P(0)-, P(25)-, P(50)-, and P(75)-P(100). Trend χ(2) test was used to analyze the trend of the detection rates of elevated blood pressure and its components in different groups of endurance quality. Logistic regression model was used to estimate the odds ratio (OR) for elevated blood pressure and its components in different endurance quality groups and P(0)-group was set as reference group. Quantile regression model was used to analyze the association between different blood pressure levels and endurance quality. Results: The detection rate of elevated blood pressure in the students aged 13-18 years in China in 2014 was 9.2%. The detection rate of elevated blood pressure and its components decreased with the improvement of endurance quality (P<0.001). With the P(0)-endurance quality group as reference, the OR(95%CI) were 0.89(0.84-0.95), 0.81(0.76-0.86) and 0.79(0.74-0.84) respectively in P(25)-, P(50)- and P(75)-P(100) endurance quality groups respectively. The negative association existed between endurance quality and elevated blood pressure in overweight, obese and normal students, but not in malnourished students. The quantile regression analysis results showed that in overweight and obese students, the SBP levels at the P(10), P(25), P(50), P(75), P(9)0 and P(95) groups were negatively associated with the endurance quality, and the DBP levels at the P(25) and above group were negatively associated with the endurance quality. In malnourished and normal students, only some levels of DBP were negatively associated with the endurance quality. Conclusions: The negative association existed between endurance quality and elevated blood pressure in Han students aged 13-18 years in China. In overweight and obese students, the association between endurance quality and blood pressure level was stronger. Improving students' endurance quality may facilitate the prevention of elevated blood pressure.


Assuntos
Hipertensão , Resistência Física , Estudantes , Adolescente , Criança , China/epidemiologia , Humanos , Hipertensão/epidemiologia , Resistência Física/fisiologia , Estudantes/estatística & dados numéricos
11.
Nat Commun ; 11(1): 4936, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024098

RESUMO

Wearable exercise trackers provide data that encode information on individual running performance. These data hold great potential for enhancing our understanding of the complex interplay between training and performance. Here we demonstrate feasibility of this idea by applying a previously validated mathematical model to real-world running activities of  ≈ 14,000 individuals with ≈ 1.6 million exercise sessions containing duration and distance, with a total distance of ≈ 20 million km. Our model depends on two performance parameters: an aerobic power index and an endurance index. Inclusion of endurance, which describes the decline in sustainable power over duration, offers novel insights into performance: a highly accurate race time prediction and the identification of key parameters such as the lactate threshold, commonly used in exercise physiology. Correlations between performance indices and training volume and intensity are quantified, pointing to an optimal training. Our findings hint at new ways to quantify and predict athletic performance under real-world conditions.


Assuntos
Modelos Teóricos , Corrida/fisiologia , Atletas , Big Data , Exercício Físico/fisiologia , Humanos , Ácido Láctico/metabolismo , Consumo de Oxigênio , Resistência Física/fisiologia , Dispositivos Eletrônicos Vestíveis
12.
Artigo em Inglês | MEDLINE | ID: mdl-32992625

RESUMO

In recent years, there has been an increasing number of investigations analyzing the effects of sex, performance level, and age on pacing in various running disciplines. However, little is known about the impact of those factors on pacing strategies in ultramarathon trail running. This study investigated the effects of age, sex, and performance level on pacing in the UTMB® (Ultra-trail du Mont Blanc) and aimed to verify previous findings obtained in the research on other running disciplines and other ultramarathon races. Data from the UTMB® from 2008 to 2019 for 13,829 race results (12,681 men and 1148 women) were analyzed. A general linear model (two-way analysis of variance (ANOVA)) was applied to identify a sex, age group, and interaction effect in pace average and pace variation. A univariate model (one-way ANOVA) was used to identify a sex effect for age, pace average, and pace variation for the fastest men and women. In our study, pace average and a steadier pace were positively correlated. Even pacing throughout the UTMB® correlated with faster finishing times. The average pace depended significantly on sex and age group. When considering the top five athletes in each age group, sex and age group also had significant effects on pace variation. The fastest women were older than the fastest men, and the fastest men were faster than the fastest women. Women had a higher pace variation than men. In male competitors, younger age may be advantageous for a successful finish of the UTMB®. Faster male runners seemed to be younger in ultramarathon trail running with large changes in altitude when compared to other distances and terrains.


Assuntos
Resistência Física , Corrida , Análise de Variância , Atletas , Feminino , Humanos , Masculino
13.
Artigo em Inglês | MEDLINE | ID: mdl-32916939

RESUMO

The aim of this study was to determine the possible correlations between essential and toxic trace elements of plasma with several anthropometric and body composition parameters and performance in endurance runners. Sixty-five high-level middle and long-distance runners (21 ± 3 years; 1.77 ± 0.05 m; 64.97 ± 7.36 kg; VO2 max. 67.55 ± 4.11 mL/min/kg) participated in the present study. Abdominal, subscapular, iliac crest, triceps, front thigh and medial calf skinfold thicknesses and an incremental test until exhaustion were recorded. Body, fat, muscle and bone mass were estimated. Plasma trace elements were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). Correlations and simple linear regression were used to assess the relationship between trace elements and several variables. Different skinfolds, fat mass, muscle mass and bone mass correlated positively and negatively with trace elements such as copper, manganese, selenium, vanadium, zinc, lithium, rubidium, strontium, arsenic, beryllium and lead. Lithium was related with performance. In conclusion, endurance training causes changes in the body concentrations of several trace elements that trigger modifications in body composition that may be interesting, if confirmed in the future, for the control of metabolic diseases such as obesity.


Assuntos
Corrida , Selênio , Oligoelementos , Composição Corporal , Humanos , Resistência Física , Corrida/fisiologia , Pregas Cutâneas , Adulto Jovem , Zinco
14.
J Cardiovasc Magn Reson ; 22(1): 62, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32878630

RESUMO

BACKGROUND: Intensive endurance exercise may induce a broad spectrum of right ventricular (RV) adaptation/remodelling patterns. Late gadolinium enhancement (LGE) has also been described in cardiovascular magnetic resonance (CMR) of some endurance athletes and its clinical meaning remains controversial. Our aim was to characterize the features of contrast CMR and the observed patterns of the LGE distribution in a cohort of highly trained endurance athletes. METHODS: Ninety-three highly trained endurance athletes (> 12 h training/week at least during the last 5 years; 36 ± 6 years old; 53% male) and 72 age and gender-matched controls underwent a resting contrast CMR. In a subgroup of 28 athletes, T1 mapping was also performed. RESULTS: High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and a slight reduction of biventricular ejection fraction, as compared to controls in both genders (p < 0.05). Focal LGE was significantly more prevalent in athletes than in healthy subjects (37.6% vs 2.8%; p < 0.001), with a typical pattern in the RV insertion points. In T1 mapping, those athletes who had focal LGE had higher extracellular volume (ECV) at the remote myocardium than those without (27 ± 2.2% vs 25.2 ± 2.1%; p < 0.05). CONCLUSIONS: Highly trained endurance athletes showed a ten-fold increase in the prevalence of focal LGE as compared to control subjects, always confined to the hinge points. Additionally, those athletes with focal LGE demonstrated globally higher myocardial ECV values. This matrix remodelling and potential presence of myocardial fibrosis may be another feature of the athlete's heart, of which the clinical and prognostic significance remains to be determined.


Assuntos
Atletas , Cardiomegalia Induzida por Exercícios , Meios de Contraste/administração & dosagem , Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Resistência Física , Função Ventricular Direita , Remodelação Ventricular , Adaptação Fisiológica , Adulto , Estudos de Casos e Controles , Feminino , Fibrose , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
15.
Sci Rep ; 10(1): 15958, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994427

RESUMO

We investigated the extent to which an un-motorized, low-profile, elastic exosuit reduced the rate of fatigue for six lumbar extensor muscles during leaning. Six healthy subjects participated in an A-B-A (withdrawal design) study protocol, which involved leaning at 45º for up to 90 s without exosuit assistance (A1), then with assistance (B), then again without assistance (A2). The exosuit provided approximately 12-16 Nm of lumbar extension torque. We measured lumbar muscle activity (via surface electromyography) and assessed fatigue rate via median frequency slope. We found that five of the six subjects showed consistent reductions in fatigue rate (ranging from 26% to 87%) for a subset of lumbar muscles (ranging from one to all six lumbar muscles measured). These findings objectively demonstrate the ability of a low-profile elastic exosuit to reduce back muscle fatigue during leaning, which may improve endurance for various occupations.


Assuntos
Dor Lombar/terapia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Braquetes , Eletromiografia/métodos , Teste de Esforço , Exoesqueleto Energizado , Feminino , Humanos , Contração Isométrica/fisiologia , Vértebras Lombares , Região Lombossacral , Masculino , Resistência Física/fisiologia , Adulto Jovem
16.
Euro Surveill ; 25(36)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32914744

RESUMO

In March 2020, we observed an outbreak of COVID-19 among a relatively homogenous group of 199 young (median age 21 years; 87% men) Swiss recruits. By comparing physical endurance before and in median 45 days after the outbreak, we found a significant decrease in predicted maximal aerobic capacity in COVID-19 convalescent but not in asymptomatically infected and SARS-CoV-2 naive recruits. This finding might be indicative of lung injury after apparently mild COVID-19 in young adults.


Assuntos
Infecções por Coronavirus/diagnóstico , Coronavirus/isolamento & purificação , Exercício Físico/fisiologia , Lesão Pulmonar/etiologia , Consumo de Oxigênio , Resistência Física/fisiologia , Pneumonia Viral/diagnóstico , Ventilação Pulmonar/fisiologia , Adulto , Infecções Assintomáticas , Betacoronavirus , Convalescença , Coronavirus/genética , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Feminino , Humanos , Masculino , Militares , Pandemias , Resistência Física/imunologia , Aptidão Física , Pneumonia Viral/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Suíça/epidemiologia , Adulto Jovem
17.
Artigo em Inglês | MEDLINE | ID: mdl-32878259

RESUMO

The time to exhaustion (tlim) at the respiratory compensation point (RCP) and whether a physiological steady state is observed at this workload remains unknown. Thus, this study analyzed tlim at the power output eliciting the RCP (tlim at RCP), the oxygen uptake (VO2) response to this effort, and the influence of endurance fitness. Sixty male recreational cyclists (peak oxygen uptake [VO2peak] 40-60 mL∙kg∙min-1) performed an incremental test to determine the RCP, VO2peak, and maximal aerobic power (MAP). They also performed constant-load tests to determine the tlim at RCP and tlim at MAP. Participants were divided based on their VO2peak into a low-performance group (LP, n = 30) and a high-performance group (HP, n = 30). The tlim at RCP averaged 20 min 32 s ± 5 min 42 s, with a high between-subject variability (coefficient of variation 28%) but with no differences between groups (p = 0.788, effect size = 0.06). No consistent relationships were found between the tlim at RCP and the different fitness markers analyzed (RCP, power output (PO) at RCP, VO2peak, MAP, or tlim at MAP; all p > 0.05). VO2 remained steady overall during the tlim test, although a VO2 slow component (i.e., an increase in VO2 >200 mL·min-1 from the third min to the end of the tests) was present in 33% and 40% of the participants in HP and LP, respectively. In summary, the PO at RCP could be maintained for about 20 min. However, there was a high between-subject variability in both the tlim and in the VO2 response to this effort that seemed to be independent of fitness level, which raises concerns on the suitability of this test for fitness assessment.


Assuntos
Ciclismo , Consumo de Oxigênio , Resistência Física , Ciclismo/fisiologia , Teste de Esforço , Humanos , Masculino , Fatores de Tempo
18.
Artigo em Inglês | MEDLINE | ID: mdl-32899413

RESUMO

Background: Chronic low back pain (CLBP) is a serious problem in Military Police Officers (MPO), which accounts for up to 45% of the sick leave rates. It has been assumed that the strength and the endurance of trunk flexor and extensor muscles are CLPB key factors, but it is not known whether these attributes are related to pain intensity. It was aimed to determine whether the strength and endurance of trunk flexor and extensor muscles differ in MPO with no pain (CON; n = 24), moderate (MOD; n = 42), and severe (SEV; n = 37) nonspecific chronic low back pain (CLBP). Methods: The peak torque and endurance test of trunk flexor (PTF.BM-1) and extensor (PTE.BM-1) muscles were compared. A multiple regression analysis was used to identify pain intensity predictors in all groups (PAIN) and according to pain intensity (MOD and SEV). Results: The PTF.BM-1 was negatively related to pain and was a significant predictor, irrespective of pain intensity (PAIN). Conclusion: When pain intensity was considered the PTF.BM-1 and PTE.BM-1 explained the pain in the MOD, while the PTE.BM-1 and service time explained pain intensity in the SEV. Endurance of the flexor and extensor muscles was not related to pain intensity. These results indicated that training protocols must emphasize specific strengthening routines.


Assuntos
Dor Lombar , Militares , Resistência Física , Adulto , Antropometria , Humanos , Músculo Esquelético , Desempenho Físico Funcional , Polícia
19.
Artigo em Inglês | MEDLINE | ID: mdl-32927832

RESUMO

The aim of this study was to investigate how family life and marital status influence the motivations of ultramarathoners. Two-hundred-sixty-seven Polish athletes participated in the diagnostic survey during the Karkonosze Winter Ultramarathon. The Polish version of the Motivation of Marathoner Scale was used. The motivations of ultra-runners were investigated among the following groups of respondents: people in a relationship/marriage; singles; people with children vs. childless people; people who run alone and with a partner; people who parted with a partner because of lack of support for running. Research results can be useful for sport managers-e.g., findings show the relative importance of modern sport for singles in the second half of life. Research has also shown how people in relationships and people with children can be realized through demanding long-distance running. We also found that running ultramarathons can pose a threat to a relationship.


Assuntos
Relações Familiares/psicologia , Estado Civil , Motivação , Corrida , Criança , Humanos , Resistência Física , Polônia
20.
J Sports Sci Med ; 19(3): 478-488, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32874100

RESUMO

There is increasing evidence that cardiorespiratory endurance (CRE) is declining among Chinese children and youth. The 20-meter shuttle run test (20-m SRT) is considered the most effective and widely used field-based measurement of CRE for children and youth worldwide. However, there have been few attempts to set 20-m SRT norms for Chinese children and youth. We aimed to develop sex- and age-specific 20-m SRT norms for Chinese children and youth, and compare them with international standards. Participants were 69,960 healthy children and youth aged 9-17 years from six geographical areas of China, selected using a stratified cluster random sampling method. Sex- and age-specific 20-m SRT percentiles and curves were extracted for four common 20-m SRT metrics (laps, completed stages/minutes, speed at the last complete stage, estimated peak oxygen uptake). We also estimated the prevalence of healthy CRE according to the interim international cut-points (42 mL.kg-1min-1 for boys, 35 mL·kg·1min-1 for girls). Chinese boys consistently outperformed girls, while more girls (86.4%) exhibited healthy CRE than boys (67.1%). Younger children and youth were more likely to meet the standards compared with the older, regardless of sex. Chinese children and youth underperformed international norms by 0.85% for boys and 3.1% for girls. The performance indicator (z-score) of Chinese children and youth was -0.01, indicating that 20-m SRT performance was worse than the international mean. The sex differences were also higher for international than Chinese students. This study provided national sex- and age-specific 20-m SRT Chinese norms, offering a valuable tool for screening, monitoring and identifying target groups for future interventions and early prevention of cardiovascular risk factors.


Assuntos
Grupo com Ancestrais do Continente Asiático , Aptidão Cardiorrespiratória , Teste de Esforço/métodos , Resistência Física/fisiologia , Corrida/fisiologia , Adolescente , Fatores Etários , Criança , China , Estudos Transversais , Feminino , Humanos , Masculino , Consumo de Oxigênio , Valores de Referência , Fatores Sexuais
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