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1.
Work ; 63(2): 231-241, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156203

RESUMO

BACKGROUND: Obesity prevalence in the workforce is clearly increasing. Simultaneously, manual lifting/lowering loads, referred to as Vertical Handling Tasks (VHT) in this paper, are common in industries and services. Performing VHT exposes workers to physical overload, which can be measured using a psychophysical approach. Various risk factors can increase this overload, including individual factors such as workers' Body Mass Index (BMI). OBJECTIVE: To study the possible effects of workers' BMI and some task conditions on physical overload during VHT. METHODS: Psychophysical data were collected from 51 participants having different body constitutions (including non-obese, overweight and obese). The participants performed 6 VHT (3 different loads ×2 workstation configurations), during which they lifted and lowered a test-box between their knees and shoulders. For each task, they reported their perceived exertion using the Borg Category Ratio-10 (CR-10) scale. RESULTS: The results showed that the CR-10 scale is sensitive to the variation of the task conditions tested. However, the psychophysical data pointed to a tendency to decrease the perception of physical overload as workers' BMI increases. CONCLUSIONS: This may compromise the validity of the application of psychophysical data as an ergonomic approach for Work-Related Musculoskeletal Disorders (WRMSD) prevention in obese workers.


Assuntos
Índice de Massa Corporal , Percepção , Esforço Físico/fisiologia , Adulto , Ergonomia/instrumentação , Ergonomia/métodos , Feminino , Humanos , Remoção/efeitos adversos , Masculino , Projetos Piloto , Psicofísica/métodos , Psicofísica/tendências , Fatores de Risco , Trabalho/fisiologia , Trabalho/psicologia
2.
Work ; 63(2): 253-259, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156206

RESUMO

BACKGROUND: Carrying a backpack and pulling a school trolley have been previously related to changes in spatiotemporal gait parameters. OBJECTIVE: Analyze gait asymmetry and rating of perceived exertion carrying a backpack and pulling a trolley with different loads. METHODS: Fifteen students from an elementary school (aged 10.1 ±â€Š1.7 years) participated in this study. The participants walked with no bag, and carrying a backpack or pulling a trolley, both with 10%, 15% and 20% of the participant's body weight (BW). A 3D motion capture system was used to analyze the spatiotemporal gait variables. Then, the ratios, symmetry angles and gait asymmetry of the step length, swing time, and stance time were analyzed. Furthermore, the rating of perceived exertion was recorded. RESULTS: None of the asymmetry parameters were significantly different between those who carried a backpack and those who pulled a trolley. In the backpack condition, the ratings of perceived exertion were higher among participants in the 20% BW (2.07 ±â€Š2.09, p = 0.003) and 10% BW (0.27 ±â€Š0.59, p = 0.004) conditions compared to those in the control condition (0.07 + 0.26). Pulling a trolley did not significantly increase the perceived exertion ratings. CONCLUSIONS: Carrying a backpack and pulling a trolley from 10% - 20% BW did not induce gait asymmetry in children. The use of the school trolley required less subjective effort than carrying a backpack with the same loads.


Assuntos
Marcha/fisiologia , Remoção , Percepção , Esforço Físico/fisiologia , Análise de Variância , Fenômenos Biomecânicos , Criança , Feminino , Análise da Marcha , Humanos , Masculino
3.
Wiad Lek ; 72(5 cz 1): 946-949, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31175802

RESUMO

OBJECTIVE: Introduction: In certain situations the constituents of food can serve as a catalysator for the formation of such a pathology as peptic ulcer. Not the last role in the formation of ulcerous defects under certain conditions play physical excertion, which is accompanied by sharp rhythmic contraction of the muscles of the anterior abdominal wall. The aim: To analyze the case of formation of "kissing" ulcers of the duodenal bulb of the 25-year-old patient. PATIENTS AND METHODS: Materials and methods: The patient took comprehensive examination: step-by-step рН-metry, esophagogastroduodenoscopy, helicobacter infection test (НР) (helicobacter urease test and microscopic examination of stained smears), histological investigations of the gastric stump mucous, HELIC - test. RESULTS: Case report: It was found that on the eve of the ulcer in the patient's diet during breakfast there was a salad of fresh white cabbage, fresh cucumbers, tomato and radishes and at lunch the patient was subjected to prolonged physical exercise. The level of gastric juice corresponded to the basal normacidity total; endoscopic diagnosis: «Kissing¼ ulcers duodenal bulb in an active stage. Chronic gastritis type B ¼. Testing for HP infection revealed a high concentration of the active form of bacteria, the HELIC -test showed a high concentration of ammonia in the stomach cavity. CONCLUSION: Conclusions: An abrupt stimulation of secretion by cabbage juice and the presence of urea in vegetables, of which the salad was cooked, led to the formation of a large level of "residual ammonia" in the cavity of the stomach. Physical strain finally formed the mechanism of ulcer formation.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Adulto , Mucosa Gástrica , Humanos , Esforço Físico , Úlcera , Verduras
4.
Int J Sports Med ; 40(7): 440-446, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31189189

RESUMO

This study aimed to evaluate the influence of physical activity on incidence of acute mountain sickness (AMS) by continuous activity monitoring in a free-living sample of South Pole workers over the initial 72 h at altitude exposure of 2,840 m (9,318 ft). Body Media activity monitors were worn by 47 healthy participants. AMS was defined by the Lake Louise symptom questionnaire. Venous blood samples were taken at sea level and approximately 48 h after high altitude exposure. AMS incidence was 34% (n=16/47) over the first 48 h and 40% (n=19/47) over 72 h. On day 2 at high altitude, individuals with AMS demonstrated a significantly greater increase in the percent change in physical activity metrics from baseline: total energy expenditure 19±13 vs. 5±7%, total steps 65±51 vs. 10±18%, metabolic equivalent of tasks 21±13 vs. 7±13%, and time spent performing moderate to vigorous physical activity 114±79 vs. 26±27% for individuals with AMS vs. no AMS, respectively, p<0.05. In addition, erythropoietin and vascular endothelial growth factor were 1.69 and 1.75 times higher, respectively, in those with AMS. In conclusion, workers who engaged in increased physical activity and activity intensity during initial exposure to the South Pole were more susceptible to developing AMS.


Assuntos
Doença da Altitude/fisiopatologia , Exercício , Esforço Físico , Doença da Altitude/sangue , Doença da Altitude/epidemiologia , Regiões Antárticas/epidemiologia , Metabolismo Energético , Eritropoetina/sangue , Monitores de Aptidão Física , Humanos , Incidência , Fatores de Risco , Fator A de Crescimento do Endotélio Vascular/sangue
6.
Invest. educ. enferm ; 37(2): [E05], 15-06-2019. Diag 1, Tab 1, Tab 2
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1007512

RESUMO

Abstract Objective. This work sought to determine the effectiveness of an aerobic exercise program on the occupational stress of nurses. Methods. Prevention-type controlled clinical trial carried out with the participation of 60 nurses working in hospitals affiliated to Shahrekord University of Medical Sciences in Iran. Randomly, the nurses were assigned to the experimental group or to the control group. The intervention consisted in an aerobic exercise program lasting three months with three weekly sessions one hour each. The Health and Safety Executive (HSE) questionnaire measured occupational stress with 35 questions, each with five Likert-type response options, which can have a maximum score of 175 points; higher scores meant lower levels of occupational stress. The HSE was evaluated during three moments: upon registering, after finishing the exercise program (week 8), and two months after terminating the intervention (week 16). Results. The level of occupational stress was the same in the experimental and control groups during registration (86.2 vs. 86.3). Upon finishing the aerobic exercise program(week 8), the experimental group showed a higher score than the control group (119.7 vs. 86.2, p<0.01), with this score diminishing after two months of having ended the intervention (91.4 vs. 85.8, p=0.061). Conclusion. The aerobic exercise program was associated to decreased work stress of nurses in the experimental group compared to the control group at eight weeks, but this difference did not persist when the experimental group did not continue with the program.


Resumen Objetivo. Determinar la efectividad de un programa de ejercicio aeróbico en el estrés ocupacional de las enfermeras. Métodos. Ensayo clínico controlado de tipo preventivo que se llevó a cabo con la participación de 60 enfermeras que trabajaban en hospitales afiliados a Shahrekord University of Medical Sciences en Irán. Las enfermeras se asignaron aleatoriamente al grupo experimental o al grupo control. La intervención consistió en un programa de ejercicio aeróbico realizado durante dos meses con tres sesiones semanales de una hora de duración. El estrés ocupacional se midió con el cuestionario Health and Safety Executive (HSE) de 35 preguntas, con opciones de respuesta tipo Likert que van de 1 a 5; puede llegar a puntuar en 175 como máximo: a mayor puntaje, menor el nivel de estrés ocupacional. Se evaluó el HSE en tres momentos: en la inscripción, después de finalizar el programa de ejercicio (semana 8) y también dos meses después de terminada la intervención (semana 16). Resultados. Fue igual el nivel de estrés ocupacional en los grupos de intervención y de control en la inscripción (86.2 vs. 86.3), pero al finalizar el programa de ejercicios aeróbicos (semana 8) el grupo experimental mostró un puntaje mayor que el del grupo control (119.7 vs. 86.2, p<0.01), para luego disminuir este puntaje a los dos meses de haber finalizado la intervención, (91.4 vs. 85.8, p=0.061). Conclusión. El programa de ejercicio aeróbico se asoció a la disminución del estrés laboral de las enfermeras en el grupo de intervención en comparación con el grupo control a las ocho semanas, pero esta diferencia no se mantuvo cuando el grupo experimental no continuó con el programa.


Resumo Objetivo. Determinar a efetividade de um programa de exercício aeróbico sobre o estresse ocupacional das enfermeiras. Métodos. Ensaio clínico controlado de tipo preventivo que se levou a cabo com a participação de 60 enfermeiras que trabalhavam em hospitais afiliados a Shahrekord University of Medical Sciences no Irã. Em forma aleatorizada, as enfermeiras foram designadas ao grupo experimental ou ao grupo controle. A intervenção consistiu num programa de exercício aeróbico realizado durante dois meses com três sessões semanais de uma hora de duração. O estresse ocupacional se mediu com o questionário Health and Safety Executive (HSE) de 35 perguntas, que tem opções de resposta tipo Likert que vão de 1 a 5, pode chegar a pontuação de 175 como máximo; a maior pontuação, é menor o nível de estresse ocupacional. Se avaliou o HSE em três momentos: a inscrição, depois de finalizar o programa de exercício (semana 8) e também dois meses depois de terminada a intervenção (semana 16). Resultados. Foi igual o nível de estresse ocupacional nos grupos de intervenção e de controle na inscrição (86.2 vs. 86.3), mas ao finalizar o programa de exercícios aeróbicos (semana 8) o grupo experimental mostrou uma pontuação maior que o do grupo controle (119.7 vs. 86.2, p<0.01), para depois diminuir esta pontuação aos dois meses de haver finalizado a intervenção, (91.4 vs. 85.8, p=0.061). Conclusão. O programa de exercício aeróbico se associou à diminuição do estresse profissional das enfermeiras no grupo de intervenção em comparação com o grupo de controle às oito semanas, mas esta diferença não se manteve quando o grupo experimental não continuou com o programa.


Assuntos
Humanos , Grupos Controle , Esforço Físico , Estresse Ocupacional , Enfermeiros
7.
J Strength Cond Res ; 33(6): 1685-1691, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31125327

RESUMO

Mangan, S, Ryan, M, Shovlin, A, McGahan, J, Malone, S, O'Neill, C, Burns, C, and Collins, K. Seasonal changes in Gaelic football match-play running performance. J Strength Cond Res 33(6): 1686-1692, 2019-Time of season influences performance in many team sports; however, the anomaly has not yet been examined with regards to elite Gaelic football. Global positioning systems (4 Hz; VX Sport, Lower Hutt, New Zealand) were used to monitor 5 elite Gaelic football teams over a period of 5 years (2012-2016). In total, 95 matches equated to 780 full player data sets. Running performance was characterized by total distance (m) and high-speed distance (≥17 km·h; m). High-speed distance was further categorized into 4 match quarters. Time of season was determined by month of the year. Time of season had a significant effect on total distance (p ≤ 0.001 partial η = 0.148) and high-speed distance (p ≤ 0.001 partial η = 0.105). August and September were significantly different from every other month for total distance (p ≤ 0.001) and high-speed distance (p ≤ 0.002). Month of season and match quarter had a significant interaction with high-speed distance (p ≤ 0.001 partial η = 0.106). High-speed distances run in the fourth quarter in August (478 ± 237 m) and in September (500 ± 219 m) were higher than any other quarter in any other month. This is the first study to show that time of season influences running performance in Gaelic football. The findings have major implications for training practices in Gaelic football.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Adulto , Sistemas de Informação Geográfica , Humanos , Masculino , Esforço Físico , Esportes/fisiologia , Fatores de Tempo , Adulto Jovem
8.
Int J Mol Sci ; 20(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052157

RESUMO

Detecting microbial interactions is essential to the understanding of the structure and function of the gut microbiome. In this study, microbial co-occurrence patterns were inferred using a random matrix theory based approach in the gut microbiome of mice in response to chondroitin sulfate disaccharide (CSD) under healthy and stressed conditions. The exercise stress disrupted the network composition and microbial co-occurrence patterns. Thirty-four Operational Taxonomic Units (OTU) were identified as module hubs and connectors, likely acting as generalists in the microbial community. Mucispirillum schaedleri acted as a connector in the stressed network in response to CSD supplement and may play a key role in bridging intimate interactions between the host and its microbiome. Several modules correlated with physiological parameters were detected. For example, Modules M02 (under stress) and S05 (stress + CSD) were strongly correlated with blood urea nitrogen levels (r = 0.90 and -0.75, respectively). A positive correlation between node connectivity of the OTUs assigned to Proteobacteria with superoxide dismutase activities under stress (r = 0.57, p < 0.05) provided further evidence that Proteobacteria can be developed as a potential pathological marker. Our findings provided novel insights into gut microbial interactions and may facilitate future endeavor in microbial community engineering.


Assuntos
Microbioma Gastrointestinal , Estresse Fisiológico , Actinobacteria/efeitos dos fármacos , Actinobacteria/isolamento & purificação , Animais , Bacteroidetes/efeitos dos fármacos , Bacteroidetes/isolamento & purificação , Sulfatos de Condroitina/efeitos adversos , Camundongos , Camundongos Endogâmicos BALB C , Esforço Físico , Proteobactérias/efeitos dos fármacos , Proteobactérias/isolamento & purificação
9.
Behav Processes ; 164: 178-185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082477

RESUMO

Organisms must frequently make cost-benefit decisions based on time, risk, and effort in choosing rewards to pursue. Various tasks have been developed to assess effort-based choice in rats, and experimenters have found largely similar results across tasks and brain regions. In this review, we focus primarily on the convergence of different effort-based choice tasks where quality or quantity of reward are manipulated. In the former, the rat is typically presented with the option to work for a preferred reward or select a less preferred, but freely-available reward. In such paradigms, the rewards are of different identities but are confirmed to differ qualitatively in value by a food preference task when both are freely-available. In the latter task type, rats are required to select between higher magnitude versus lower magnitudes of the same reward, but each with a similar effort requirement. We discuss the strengths/limitations of these paradigms, and describe brain regions that have been probed that result in converging or equivocal findings. Results are also reviewed with reference to a need for future work, and the broader impacts and implications of studies probing the mechanisms of effort.


Assuntos
Comportamento de Escolha , Esforço Físico , Animais , Tomada de Decisões , Preferências Alimentares , Recompensa
10.
Kardiologiia ; 59(4S): 51-58, 2019 May 24.
Artigo em Russo | MEDLINE | ID: mdl-31131760

RESUMO

Actuality. In the basic therapy of CHF, drugs that reduce the pulse is one of the leading places. Target values of heart rate with sinus rhythm are established. Tere is still no consensus as to which heart rate is ideal in patients with CHF on the background of the rhythm of atrial fbrillation (AF). Te study of the prognosis in patients with CHF and AF depending on the achieved heart rate is relevant. OBJECTIVE: To analyze the overall mortality and establish the stratifcation risks of death in patients with CHF and AF depending on the form of AF, functional class of CHF and the presence of tachycardia. MATERIAL AND METHODS: A prospective cohort study was conducted in a group of patients with CHF who were observed at the City Center for CHF treatment (n = 591) during the year. Of these, 47.4% of patients had CHF and AF (n = 280) and 52.6% of patients with CHF without AF (n = 311). RESULTS: In a year, a permanent AF registered among patients with CHF and AF in 55.4%, persistent - in 36.4%, and paroxysmal - in 8.2% of cases. In 12.2% of patients, the diagnosis of AF was frst diagnosed. According to functional class of CHF, LVEF, assessment of clinical assessment scale, the group with a permanent AF was signifcantly heavier than without AF. Te mortality of patients with tachycardia signifcantly increased as a function of the increase in CHF from I-II to III-IV class: from 3.6% to 14.9% in the group without AF (p=0.04), and in the group with paroxysmal and persistent AF from 6.7% to 25.9% (p = 0.043). Te presence of tachycardia increases the risk of death by 61%, and the transition to a heavier functional class is 4.9 times. With each increase in the clinical assessment scale exponent by 1 point, the mortality rate in the sample is increased by 16%. CONCLUSION: Heart rate is not an independent predictor of death, but in combination with functional class III-IV CHF tachycardia signifcantly worsens the prognosis.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Doença Crônica , Hemodinâmica , Humanos , Esforço Físico , Prognóstico , Estudos Prospectivos
11.
Bull Cancer ; 106(6): 527-537, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31122656

RESUMO

BACKGROUND: The aim of this investigation was to study the effects of supervised combined intermittent aerobic, muscle strength and home-based walking training programs on cardiorespiratory fitness in women with breast cancer during adjuvant chemotherapy treatment. METHODS: Thirty-two women with breast cancer undertaking adjuvant chemotherapy participated in the study (trained group n=20 and control group n=12). The trained group carried out 6weeks of supervised intermittent cycling aerobic, muscle strength and home-based walking training programs. The self-selected walking speed (WS), walking distance covered (WD), heart rate (rHR), blood lactate ([La]b) concentration and rating of perceived exertion (RPE) were assessed in the two groups during the 6-min walking test before and after the training period. RESULTS: Compared to controls, a significant increase in the WS (P<0.01) and the WD (P<0.01) accompanied by a significant decrease in resting rHR (P<0.01), exercising HR6' (P<0.01), [La]b (P<0.05), HR6'/WS (P<0.01) and [La]b/WS ratios (P<0.01) was reported in the trained group. However, a significant decrease both in WD (P<0.01) and WS (P<0.01) has been observed in the controls. No significant difference was observed in resting HR, exercising HR6', [La]b, HR6'/WS, and [La]b/WS ratios were observed in the control group. A significant improvement was observed for RPE in training group (P<0.05). However, no difference was shown in controls. CONCLUSION: Combined training based on intermittent aerobic exercise, muscle strength and walking improve cardiorespiratory responses and reduce the perception of fatigue in women with breast cancer.


Assuntos
Neoplasias da Mama/reabilitação , Aptidão Cardiorrespiratória , Exercício , Treinamento de Resistência , Caminhada , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Docetaxel/administração & dosagem , Epirubicina/administração & dosagem , Teste de Esforço , Feminino , Fluoruracila/administração & dosagem , Frequência Cardíaca , Serviços de Assistência Domiciliar/organização & administração , Humanos , Lactatos/sangue , Pessoa de Meia-Idade , Esforço Físico , Avaliação de Programas e Projetos de Saúde
12.
R I Med J (2013) ; 102(4): 23-29, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31042340

RESUMO

OBJECTIVE: To assess the effect of a device-assisted out- of-hospital cardiac arrest (OHCA) resuscitation approach on provider performance during simulated transport. METHODS: BLS and ALS providers were randomized into control and experimental teams. Subjects were fitted with wireless heart rate (HR) monitors. Control teams simulated with standard protocols and equipment; experimental teams with resuscitation-automating devices and goal-directed protocols. Chest compression quality, pulmonary ventilation, defibrillation, and medication administration tasks were monitored; subjects' HR's were continuously recorded. RESULTS: Ten control and ten experimental teams completed the study (20 EMT-B's; 1 EMT-I, 8 EMT-C's, 11 EMT-P's) with similar resting HR's and age-predicted maximal HR's (mHR). All exhibited suboptimal in-transit resuscitation quality during initial simulations; HR did not differ significantly between the groups. Experimental teams exhibited improved chest compression and ventilation quality during transport along with lower subject HR. CONCLUSION: OHCA resuscitation automation improved the in-simulation quality of critical in-transit tasks and reduced provider exertion.


Assuntos
Reanimação Cardiopulmonar/instrumentação , Frequência Cardíaca , Parada Cardíaca Extra-Hospitalar/terapia , Esforço Físico , Treinamento por Simulação , Adulto , Reanimação Cardiopulmonar/educação , Reanimação Cardiopulmonar/métodos , Auxiliares de Emergência , Feminino , Humanos , Masculino , Adulto Jovem
13.
J Sport Exerc Psychol ; 41(2): 107-118, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31046538

RESUMO

The extent to and manner in which psychological states change as a function of physical effort and related physiological responses have been addressed separately in various theoretical frameworks. The authors explored a proposed conceptual scheme examining the relationships among perceived exertion, attentional allocation, and affective responses under different workload domains. Thirty male participants performed an incremental cycling test to assess the progression of rating of perceived exertion, attentional focus, affect, and felt arousal along a parallel increase in heart rate using ventilatory threshold as a reference point. Results revealed that ventilatory threshold acts as a metabolic landmark for the attentional shifts toward aversive sensory cues, sustained increases in perceived exertion, negative valence, and physiological activation. Monitoring the dynamics of perceived exertion, attention, and affect can complement physiological measures for an accurate control of training workloads during exercise prescription.


Assuntos
Atenção , Cognição , Exercício/fisiologia , Esforço Físico , Carga de Trabalho , Adulto , Afeto , Nível de Alerta , Teste de Esforço , Frequência Cardíaca , Humanos , Masculino , Adulto Jovem
14.
Nutrients ; 11(4)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934886

RESUMO

The ergogenicity of caffeine on several exercise and sport situations is well-established. However, the extent of the ergogenic response to acute caffeine ingestion might greatly vary among individuals despite using the same dosage and timing. The existence of one or several individuals that obtained minimal ergogenic effects or even slightly ergolytic effects after caffeine intake (i.e., non-responders) has been reported in several previous investigations. Nevertheless, the concept non-responding to caffeine, in terms of physical performance, relies on investigations based on the measurement of one performance variable obtained once. Recently it has been suggested that correct identification of the individual ergogenic effect induced by caffeine intake requires the repeated measurement of physical performance in identical caffeine⁻placebo comparisons. In this communication, we present data from an investigation where the ergogenic effect of acute caffeine intake (3 mg/kg) was measured eight times over a placebo in the same individuals and under the same conditions by an incremental cycling test to volitional fatigue and an adapted version of the Wingate cycling test. The ergogenic response to caffeine varied from 9% to 1% among individuals, but all participants increased both cycling power in the incremental test and Wingate mean power at least three to eight times out of eight the caffeine⁻placebo comparisons. These data expand the suggestion of a minimal occurrence of caffeine non-responders because it shows that all individuals responded to caffeine when caffeine is compared to a placebo on multiple and repeated testing sessions.


Assuntos
Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Resistência Física/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Adulto , Estudos Cross-Over , Fadiga , Humanos
15.
J Sports Sci ; 37(16): 1816-1823, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30931825

RESUMO

Research remains unclear on the impact of physiological load on perceptual-cognitive skills in sport. Moreover, no study has examined the training of perceptual-cognitive skills under physiological load. The current study comprised two phases. Firstly, we examined the impact of badminton-specific physiological load on anticipatory skills in expert badminton players (n = 13), including key underlying mechanisms, such as gaze behaviour. Under high physiological load, participants displayed less efficient visual search behaviour and showed a reduction in response accuracy. Secondly, we examined the effects of combining perceptual-cognitive simulation training with the high physiological load. Ten of the expert badminton players were assigned to a combined training group, where the simulation training and the physiological load intervention occurred simultaneously or an independent training group, whereby the two components were completed independently. The combined training group showed a positive change in the efficiency of their visual search behaviours compared to the independent training group, but no significant performance improvements were found. Overall, findings demonstrate that high physiological load is detrimental to experts' anticipatory skills. However, combining perceptual-cognitive simulation training with high physiological load can potentially negate these debilitating effects.


Assuntos
Antecipação Psicológica/fisiologia , Condicionamento Físico Humano/métodos , Esportes com Raquete/fisiologia , Esportes com Raquete/psicologia , Percepção Visual/fisiologia , Adulto , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Cognição/fisiologia , Fixação Ocular/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Percepção/fisiologia , Esforço Físico/fisiologia , Adulto Jovem
16.
J Sports Sci ; 37(16): 1824-1830, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30939987

RESUMO

The menstrual cycle (MC) phases carry to several psychophysiological alterations; however, no study has investigated the impact of MC phases on training load or technical training. In the present study, we investigated the effect of the follicular phase (FP), ovulatory phase (OP), and luteal phase (LP) on training load and technical training in young athletes. Twelve female athletes performed regular daily training sessions with the rating of perceived exertion (RPE) and duration being registered every session. Training impulse (TRIMP), monotony and strain were calculated. MC symptoms, RPE, and duration were also measured during technical training, which was carried out on a specific day during each phase. The TRIMP was not affected by MC phases during regular training (p > .05), but training monotony and strain were higher in FP compared to OP (p < .05). During the technical training, MC phases did not affect RPE (p > .05), but the session was longer in both FP and LP, compared to OP (p < .05). MC symptoms were exacerbated in FP compared to both OP and LP (p < .05). These findings suggest that MC disorders were elevated during FP, which indicate that monitoring MC phases might provide important feedbacks for programming training and expected results during competitions.


Assuntos
Ciclo Menstrual/fisiologia , Ciclo Menstrual/psicologia , Condicionamento Físico Humano/fisiologia , Condicionamento Físico Humano/psicologia , Atletismo/fisiologia , Atletismo/psicologia , Adolescente , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Frequência Cardíaca/fisiologia , Humanos , Hormônio Luteinizante/sangue , Percepção/fisiologia , Condicionamento Físico Humano/métodos , Esforço Físico/fisiologia , Progesterona/sangue , Estresse Psicológico , Fatores de Tempo
17.
J Sports Sci ; 37(16): 1857-1864, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30961440

RESUMO

The purpose was to examine changes in the perceptual responses to lifting a very low load (15% one repetition maximum (1RM)) with and without (15/0) different pressures [40% (15/40) and 80% (15/80) arterial occlusion pressure] and compare that to traditional high load (70/0) resistance exercise. Ratings of perceived exertion (RPE) and discomfort were measured following each set of exercise. In addition, resting arterial occlusion pressure was measured prior to exercise. Assessments were made in training sessions 1, 9, and 16 for the upper and lower body. Data are presented as means and 95% CI. There were changes in RPE in the upper body with condition 15/40 [-2.1 (-3.4, -0.850)] and 15/80 [-2.4 (-3.6, -1.1)] decreasing by the end of training. In the lower body, RPE decreased in condition 15/40 [-1.4 (-2.3, -0.431)] by the end of the training study. There was a main effect of time in the upper body with all conditions decreasing discomfort. In the lower body, all conditions decreased except for 15/80. For arterial occlusion pressure, there were differences across time in the 15/40 condition and the 15/80 condition in the upper body. Repeated exposure to blood flow restriction may dampen the perceptual responses over time.


Assuntos
Braço/irrigação sanguínea , Percepção/fisiologia , Esforço Físico/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Treinamento de Resistência/métodos , Coxa da Perna/irrigação sanguínea , Adaptação Fisiológica , Adolescente , Adulto , Artérias/fisiologia , Feminino , Humanos , Masculino , Músculo Esquelético/irrigação sanguínea , Adulto Jovem
18.
J Sports Sci ; 37(16): 1892-1898, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31002286

RESUMO

The aim of the study was to evaluate the effect of maximal specific physical effort on postural balance and rifle stability in biathletes in a standing shooting position. The study included 10 junior elite biathletes. The measurements were taken with the Vicon system and AMTI force platform. Postural balance and rifle stability characteristics were determined at rest as well as 1 and 5 min post maximal specific physical effort which was performed on a ski ergometer and continued until exhaustion. Maximal physical effort exerted a significant effect on all examined postural sway and rifle sway characteristics. The duration of the post-exercise changes was longer than 5 minutes. Higher post-effort rifle sway was observed in the vertical direction than in the across the shooting line direction. Post-effort postural balance impairment in the shooting line was much greater than in the across the shooting line direction. Moreover, a strong correlation was found between postural balance and rifle stability. Maximal physical effort influenced postural balance and rifle stability during aiming. Rifle sway during aiming in a standing shooting position seems to be coordinated with the postural sway of the biathlete's body. Thus, an increase in postural sway contributes to greater sway and lesser stability of the rifle.


Assuntos
Armas de Fogo , Fadiga Muscular/fisiologia , Esforço Físico/fisiologia , Equilíbrio Postural/fisiologia , Esportes/fisiologia , Posição Ortostática , Adolescente , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Esqui/fisiologia
19.
Nutrients ; 11(4)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987366

RESUMO

Intensive exercise can lead to oxidative stress, which can be particularly deleterious for lymphoid tissues. Hesperidin has demonstrated its antioxidant activity, but few studies focus on its influence on intensive training. The aim of this study was to assess the impact of hesperidin on the oxidant/antioxidant status of lymphoid tissues after an intensive training program. Wistar rats were trained for five weeks (five days per week), including two exhaustion tests plus three trainings per week. During this period, animals were orally administrated with 200 mg/kg of hesperidin or vehicle (three days per week). The oxidative status was determined before, immediately after and 24 h after an additional exhaustion test. The production of reactive oxygen species (ROS) by peritoneal macrophages, superoxide dismutase (SOD) and catalase activities in spleen, thymus and liver, and hepatic glutathione peroxidase activity (GPx) were assessed. Hesperidin prevented an increase in ROS production induced by the additional exhaustion test. Likewise, hesperidin avoided a decrease in SOD and catalase activities in the thymus and spleen that was found after the additional exhaustion test. The antioxidant effects of hesperidin were associated with a higher performance in the assessed training model. These results suggest that hesperidin, acting as an antioxidant, can prevent oxidative stress induced by exercise and improve exercise performance.


Assuntos
Antioxidantes/farmacologia , Tolerância ao Exercício/efeitos dos fármacos , Hesperidina/farmacologia , Tecido Linfoide/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal , Esforço Físico , Animais , Catalase/metabolismo , Células Cultivadas , Feminino , Glutationa Peroxidase/metabolismo , Tecido Linfoide/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo
20.
Artigo em Inglês | MEDLINE | ID: mdl-30978951

RESUMO

Manual material handling (MMH) tasks create a burden for workers which could result in musculoskeletal injuries. Assessments of the decrease of muscular strength and the maximum endurance time (MET) for MMH tasks are essential in studying the ergonomic risk of MMH tasks. A backpacking experiment was conducted for measuring the MET for MMH tasks. Human participants carried a load on their back and walked on a treadmill under various load, walking speed, and ramp angle conditions until they coud no longer do so. It was found that the participants were able to walk for approximately 15 min to two hours before they needed to have a pause. Their back and leg strengths declined moderately due to performing the tasks. These tasks resulted in an increase in heart rate and elevated perceived physical exertion. The rating of perceived exertion (RPE)/heart rate ratio in our backpacking tasks was 31% higher than that in the literature, implying the calibration of the RPE may be required for such tasks. A MET model incorporating the fMVC_back, body weight, walking speed, and ramp angle was established. This model may be used to determine the work/rest allowance for backpacking tasks under conditions similar to this study.


Assuntos
Treino Aeróbico/métodos , Frequência Cardíaca/fisiologia , Força Muscular/fisiologia , Resistência Física/fisiologia , Esforço Físico/fisiologia , Caminhada/fisiologia , Adulto , Teste de Esforço , Feminino , Humanos , Masculino
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