RESUMO

This study investigated the effectiveness of supplementing regular preseason soccer training with a supramaximal intermittent shuttle-run training (ISRT) model prescribed from Carminatti's Test peak speed (PST-CAR) in aerobic performance-related indices and sprinting speed in male junior soccer players. Twenty-three national-level soccer players (mean ± SD; age 18.07 ± 0.9 y, body height 1.76 ± 0.65 m, body mass 71.9 ± 8.7 kg) were assigned to either an experimental group (EG; n = 13) performing ISRT + soccer training or a control group (CG; n = 10) that followed regular preseason soccer training alone. The following tests were applied before and after the eight-week training intervention: (i) incremental treadmill tests (VO2max and lactate minimum speed - LMS); (ii) linear 30-m sprint test and Carminatti's Test (PST-CAR). Results indicated larger gains for the EG in LMS (Δ = 9.53% vs. 2.82%) and PST-CAR (Δ = 5.50% vs. 2.10%) than in the CG. Furthermore, changes in VO2max produced higher effect size (d) values for the EG (Δ = 6.67%; d = 0.59) than the CG (Δ = 1.88%; d = 0.18). Both groups improved (p = 0.002) their flying 20-m sprint speed (EG: Δ = 1.01%; CG: Δ = 1.56%). However, small decreases were observed for 10-m sprint speed in the CG (Δ = -2.19%; d = -0.44), while only trivial changes were noticed for the EG (Δ = -0.50%; d = -0.16). Our data support that additional supramaximal ISRT is an effective training stimulus to enhance aerobic performance-related indices and promote small improvements in maximal running speed without impairing the soccer players' acceleration capacity. This study also shows that PST-CAR can be useful for individualizing running intensity in supramaximal ISRT modes.

RESUMO

This study aimed to assess the predictive capability of different critical power (CP) models on cycling exercise tolerance in the severe- and extreme-intensity domains. Nineteen cyclists (age: 23.0 ± 2.7 y) performed several time-to-exhaustion tests (Tlim) to determine CP, finite work above CP (W'), and the highest constant work rate at which maximal oxygen consumption was attained (IHIGH). Hyperbolic power-time, linear power-inverse of time, and work-time models with three predictive trials were used to determine CP and W'. Modeling with two predictive trials of the CP work-time model was also used to determine CP and W'. Actual exercise tolerance of IHIGH and intensity 5% above IHIGH (IHIGH+5%) were compared to those predicted by all CP models. Actual IHIGH (155 ± 30 s) and IHIGH+5% (120 ± 26 s) performances were not different from those predicted by all models with three predictive trials. Modeling with two predictive trials overestimated Tlim at IHIGH+5% (129 ± 33 s; p = 0.04). Bland-Altman plots of IHIGH+5% presented significant heteroscedasticity by all CP predictions, but not for IHIGH. Exercise tolerance in the severe and extreme domains can be predicted by CP derived from three predictive trials. However, this ability is impaired within the extreme domain.

RESUMO

Background: The 6-minute rowing ergometer test (6-minRT) is valid and reliable for establishing maximal aerobic power (MAP) in amateur male rowers. However, ventilatory thresholds (VTs) have not yet been established with their mechanical correspondence in this test. Objective: The primary objective was to determine the VTs in the 6-minRT achieved by amateur male rowers, while the secondary objective was to determine the correspondence between ventilatory, mechanical, and heart rate (HR) outcomes of the 6-minRT. Methods: Sixteen amateur male rowers were part of the study. All participants were instructed to perform an incremental test (IT) and a 6-minRT. Determination of the ventilatory parameters for the first ventilatory threshold (VT1), the second ventilatory threshold (VT2), and 6minRTVO2max were performed by correlating the outcomes of VT1, VT2, and VO2max obtained in the IT, with the outcomes of 6-minRT. For these purposes, Pearson's test was used, with the following criteria: trivial, <0.1; small, 0.1-0.3; moderate, 0.3-0.5; high, 0.5-0.7; very high, 0.7-0.9; or practically perfect, >0.9. The significance level was p < 0.05. Results: The IT analysis determined that VT1 and VT2 correspond to 55 and 80% of VO2max, respectively. A high correlation was observed between IT outcomes in VT1, VT2, and VO2max, with the outcomes of 6-minRT (r > 0.6). Conclusion: Based on IT ventilatory parameters and concordance analysis, VT1 and VT2 of 6-minRT are determined at 55 and 80%, respectively, of both ventilatory parameters and their corresponding mechanical outcomes and HR.

Assuntos

Teste de Esforço , Esportes Aquáticos , Humanos , Masculino , Ergometria , Atletas

RESUMO

BACKGROUND: Post-menopausal women have impaired cardiorespiratory responses to exercise compared to young women. Exercise training may counterbalance impairments, but the time-dependent effects of exercise training remain unclear. The current study aims to investigate the effects of rowing training on maximal aerobic capacity and time-course cardiorespiratory adaptations in older women. METHODS: Female participants (n = 23) were randomly allocated to the experimental group (EXP; n = 23; 66 ± 5 years old) enrolled in rowing exercise training and control group (CON; n = 10; 64 ± 4 years old). The cardiopulmonary exercise test (CET) was performed in a cycle ergometer pre- and post-interventions. Oxygen uptake (VO2), stroke volume (SV), cardiac output (CO), and HR were recorded during CET and analyzed at the peak of the exercise. HR was monitored during exercise recovery, and the index of HRR was calculated by ΔHRR (HRpeak-HR one-minute recovery). Every two weeks, Rowing Stepwise Exercise (RSE) in a rowing machine was performed to track specific adaptations to the exercise modality. HR was continuously recorded during RSE and corrected for the average power of each step (HR/watts). The rowing training protocol consisted of three weekly sessions of 30 min at an intensity corresponding to 60-80% of peak HR for ten weeks. RESULTS: Rowing exercise training increased VO2, SV, and CO at the peak of the CET, and ΔHRR. Increased workload (W) and reduced HR response to a greater achieved workload (HR/W) during RSE were observed after six weeks of training. CONCLUSIONS: Rowing exercise training is a feasible method to improve cardiorespiratory performance, vagal reactivation and heart rate adjustments to exercise in older women.

Assuntos

Pós-Menopausa , Esportes Aquáticos , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Exercício Físico/fisiologia , Ergometria , Teste de Esforço , Frequência Cardíaca/fisiologia , Consumo de Oxigênio

RESUMO

Maximal oxygen consumption (V̇O2max), physiological thresholds, and hemoglobin mass are strong predictors of endurance performance. High values of V̇O2max, maximal aerobic power (MAP), and power output at anaerobic thresholds are key variables in elite rowers. Endurance athletes often use altitude training as a strategy to improve performance. However, no clear evidence exists that training at natural altitude enhances sea-level performance in elite rowers. This study aimed to evaluate the effect of altitude training on rowing-performance parameters at sea level. The study was conducted on eleven rowers (Six females, five males) from the Chilean National Team during a 3-week moderate altitude training (∼2,900 m. a.s.l.) under the live high-train high (LHTH) model. It included a rowing ergometer maximal incremental test and blood analysis (pre and post-altitude). Gas exchange analysis was performed to measure V̇O2max, ventilatory thresholds (VTs) and rowing economy/efficiency (ECR/GE%). LHTL training improves performance-related variables at sea level (V̇Emax: 3.3% (95% CI, 1.2-5.5); hemoglobin concentration ([Hb]): 4.3% (95% CI, 1.7-6.9); hematocrit (%): 4.5% (95% CI, 0.9-8.2); RBC (red blood cells) count: 5.3% (95% CI, 2.3-8.2); power at VT2: 6.9% (95% CI, 1.7-12.1), V̇EVT2: 6.4% (95% CI, 0.4-12.4); power at VT1: 7.3% (95% CI, 1.3-13.3), V̇EVT1: 8.7% (95% CI, 1.6-15.8)) and economy/efficiency-related variables (ECRVT2: 5.3% (95% CI, -0.6 to -10.0); GE(%): 5.8% (95% CI, 0.8-10.7)). The LHTH training decreased breathing economy at MAP (-2.8% (95% CI, 0.1-5.6)), pVT2 (-9.3% (95% CI, -5.9 to -12.7)), and pVT1 (-9.3% (95% CI, -4.1 to -14.4)). Non-significant changes were found for V̇O2max and MAP. This study describes the effects of a 3-week moderate altitude (LHTH training) on performance and economy/efficiency-related variables in elite rowers, suggesting that it is an excellent option to induce positive adaptations related to endurance performance.

RESUMO

The prediction of running performance at different competitive distances is a challenge, since it can be influenced by several physiological, morphological and biomechanical factors. In experienced male runners heterogeneous for maximal oxygen uptake (VO2max), endurance running performance can be well predicted by several key parameters of aerobic fitness such as VO2max and its respective velocity (vVO2max), running economy, blood lactate response to exercise, oxygen uptake kinetics and critical velocity. However, for a homogeneous group of well-trained endurance runners, the relationship between aerobic fitness parameters and endurance running performance seems to be influenced by the duration of the race (i.e., middle vs. long). Although middle-distance and ultramarathon runners present high aerobic fitness levels, there is no accumulating evidence showing that the aerobic key parameters influence both 800-m and ultramarathon performance in homogeneous group of well-trained runners. The vVO2max seems to be the best predictor of performance for 1500 m. For 3000 m, both vVO2max and blood lactate response to exercise are the main predictors of performance. Finally, for long distance events (5000 m, 10,000 m, marathon and ultramarathon), blood lactate response seems to be main predictor of performance. The different limiting/determinants factors and/or training-induced changes in aerobic parameters can help to explain this time- or distance-dependent pattern.

RESUMO

This study aimed to examine the acute physiological effect of shuttle-run-based high-intensity intermittent exercise (HIIE) performed at the same relative speed (i. e., 100% PST-CAR) on sand (SAND) and grass (GRASS) in male junior soccer players. Seven Under-23 Brazilian national league ("Série A") soccer players completed four testing sessions in either SAND or GRASS surface condition. The first two testing sessions consisted of performing a maximal progressive shuttle-run field protocol until volitional exhaustion (Carminatti's test, T-CAR), whereas the third and fourth sessions comprised a HIIE session on each ground surface. The HIIE session consisted of three 5-min bouts [12 s shuttle-run (with a direction change every 6 s)/12 s of passive rest] performed at 100% of T-CAR peak speed (PST-CAR) with 3 min of passive recovery between sets. Measurements of oxygen uptake (VO2), heart rate (HR), blood lactate concentration ([La]), and rating of perceived exertion (RPE) were performed during all conditions. The SAND condition elicited significantly higher %VO2peak (94.58 ± 2.73 vs. 87.45 ± 3.31%, p < 0.001, d = 2.35), %HRpeak (93.89 ± 2.63 vs. 90.31 ± 2.87%, p < 0.001, d = 1.30), RPE (8.00 ± 0.91 vs. 4.95 ± 1.23 a.u., p < 0.001, d = 2.82), and [La] (10.76 ± 2.37 vs. 5.48 ± 1.13 mmol/L, p < 0.010, d = 2.84). This study showed that higher internal workloads are experienced by the players during a single HIIE session performed on a softer surface as SAND, even when the exercise intensity was individualized based on 100%PST-CAR.

RESUMO

BACKGROUND: Some studies have been conducted to verify the effects of Pilates for individuals who are obese, but conclusive results are not yet available due to methodological concerns. The present study aims to verify and compare the effects of Pilates and aerobic training on cardiorespiratory fitness, isokinetic muscular strength, body composition, and functional task outcomes for individuals who are overweight/obese. METHODS: Of the sixty participants, seventeen were allocated to the control group, since the intervention protocol (Pilates or walking sessions) was during their working hours. The remaining 44 participants were randomly allocated to one of two experimental groups (Pilates (n = 22)) or aerobic groups (n = 21).The Pilates and aerobic groups attended 60-min exercise sessions, three times per week for 8 weeks. The aerobic group performed walking training at a heart rate corresponding to the ventilatory threshold. The Pilates group performed exercises on the floor, resistance apparatus, and 1-kg dumbbells. The control group received no intervention. All volunteers were evaluated at the beginning and end of the intervention. The following assessments were conducted: food intake, cardiorespiratory maximal treadmill test, isokinetic strength testing, body composition and anthropometry, abdominal endurance test, trunk extensor endurance test, flexibility test and functional (stair and chair) tests. RESULTS: There was no significant difference pre- and post-intervention in calorie intake [F(2, 57) = 0.02744, p = 0.97)]. A significant improvement in oxygen uptake at ventilatory threshold (p = 0.001; d = 0.60), respiratory compensation point (p = 0.01; d = 0.48), and maximum effort (p = 0.01; d = 0.33) was observed only in the Pilates group. Isokinetic peak torque for knee flexor and extensor muscles did not change for any groups. Lean mass (p = 0.0005; d = 0.19) and fat mass (p = 0.0001; d = 0.19) improved only in the Pilates group. Waist and hip circumference measurements decreased similarly in both experimental groups. Abdominal test performance improved more in the Pilates group (p = 0.0001; d = 1.69) than in the aerobic group (p = 0.003; d = 0.95). Trunk extensor endurance and flexibility improved only in the Pilates group (p = 0.0003; d = 0.80 and p = 0.0001; d = 0.41, respectively). The Pilates group showed greater improvement on the chair and stair tests (p = 0.0001; d = 1.48 and p = 0.003; d = 0.78, respectively) than the aerobic group (p = 0.005; d = 0.75 and p = 0.05; d = 0.41, respectively). CONCLUSION: Pilates can be used as an alternative physical training method for individuals who are overweight or obese since it promotes significant effects in cardiorespiratory fitness, body composition, and performance on functional tests.

RESUMO

Excess weight and obesity are major risk factors for many chronic diseases, and weight-loss interventions often include systematic exercise and nutritional supplements. The purpose of this study was to determine the independent/synergistic effects of Arthrospira (Spirulina) maxima supplementation (six weeks, 4.5 g·day-1) and a systematic physical exercise program (six weeks, twice weekly) on the body composition and cardiorespiratory fitness of overweight and obese subjects. To achieve this, 27 overweight and 25 obese sedentary male subjects were assigned to four interventions through a randomized double-blind, crossover controlled trial: A physical exercise program, with (SE) or without (Ex) Spirulina maxima; or no-exercise program, with (Sm) and without (C) Spirulina maxima. The body composition and cardiorespiratory fitness parameters were taken during a maximum intensity test. As compared to the C group, the body fat percentage of the SE, Sm and Ex groups was reduced (p < 0.05), while their maximal oxygen uptake improved (r = -0.40), and obese subjects benefited more significantly. Weight loss, the time to reach fatigue and the onset of blood lactate accumulation were improved in both of the Spirulina maxima supplemented groups, regardless of the subjects' body weight. Spirulina maxima supplementation synergistically improves the effects of systematic exercise on body composition and cardiorespiratory fitness parameters in overweight, but mostly in individuals with obesity. TRIAL REGISTRATION: Clinical Trials, NCT02837666. Registered 19 July 2016.

Assuntos

Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologia , Sobrepeso/tratamento farmacológico , Sobrepeso/fisiopatologia , Spirulina/química , Adulto , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Suplementos Nutricionais , Método Duplo-Cego , Terapia por Exercício/métodos , Humanos , Masculino , Obesidade/tratamento farmacológico , Obesidade/fisiopatologia , Redução de Peso/efeitos dos fármacos , Redução de Peso/fisiologia

RESUMO

Resumen: Introducción: La fibrosis quística (FQ) es una enfermedad multisistémica hereditaria y progresiva. Una mejor capacidad física puede retardar la progresión de la enfermedad, mejorando así el pronós tico y la supervivencia. El objetivo de esta investigación fue evaluar la capacidad física de los niños admitidos en el programa nacional de FQ de la Región Metropolitana, Chile. Pacientes y Método: Se utilizó un diseño de estudio transversal multicéntrico. Los criterios de inclusión fueron: niños de 6 a 12 años de edad, incluidos en el Programa Nacional de FQ, madurez sexual Tanner I, ausencia de exacerbaciones respiratorias en los últimos 30 días y ausencia de enfermedades musculoesqueléticas. La capacidad aeróbica máxima fue evaluada a través del consumo pico de oxígeno (VO2pico) y se determinó con un protocolo incremental en un cicloergómetro magnético conectado a un ergoespirómetro en el que paralelamente se analizaron los gases respiratorios: valores de consumo de oxí geno y producción de dióxido de carbono cada 30 segundos, umbral anaeróbico y carga máxima de trabajo. Además, se evaluaron los valores de capacidad vital forzada (CVF), volumen espiratorio al primer segundo (VEFj), relación VEFj/CVF y los flujos espiratorios forzados entre el 25 y 75% de la capacidad vital. Durante la prueba se registró: saturación arterial de oxígeno, frecuencia respiratoria, frecuencia cardíaca, presión arterial, volumen corriente y se consultó la percepción de fatiga de extre midades inferiores y disnea a través de la escala de Borg modificada. La duración aproximada del test fue alrededor de 10 minutos. Resultados: Se revisaron los registros clínicos de 43 niños, recogidos en seis centros de salud. Veintinueve niños cumplieron los criterios de inclusión siendo 23 reclutados. Dos niños no pudieron participar, reduciendo el grupo final de sujetos a 21 (13:8 varones:mujeres). La edad media fue de 8,8 ± 2 años; el peso fue de 30,5 ± 10,9 kg; la talla fue de 1,32 ± 0,11 m y el índice de masa corporal fue de 17,1 ± 3,5 (z-score 0,01 ± 1,34). Más de la mitad (61%) de los niños estaba eutrófico. El VO2pico obtenido fue de 43,7 ± 6,5 ml/min/kg (106,7 ± 19,8% de los valores teóricos de referencia). Sólo el 10% de los niños tenían valores inferiores a los valores teóricos esperados para población normal, ajustados por sexo y edad. No se encontraron correlaciones entre el VO2pico y las variables antropométricas y de función pulmonar. Conclusión: La mayoría de los niños evaluados (90%) tenían capacidad física similar a los valores teóricos de referencia para niños sanos ajustados por sexo y edad.

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Abstract: Introduction: Cystic fibrosis (CF) is an inherited, progressive, multisystem disease. Better physical capacity may slow disease progression, thus improving prognosis and survival. The objective of this research was to evaluate the physical capacity of children admitted to the National CF Pro gram of the Metropolitan Region, Chile. Patients and Method: A multicenter, cross-sectional stu dy design was used. The inclusion criteria were children aged 6 to 12 years enrolled in the National CF Program; Tanner sexual maturity stage I, no respiratory exacerbations in the last 30 days, and no musculoskeletal pathologies. The maximum aerobic capacity was assessed through the peak oxygen uptake (VO2peak) and determined with an incremental protocol in a magnetic cycle ergometer connected to an ergo-spirometer with which, at the same time, respiratory gases, oxygen consumption and carbon dioxide production values every 30 seconds, anaerobic threshold, and maximum workload were analyzed. The values of forced vital capacity (FVC), forced expiratory volume in 1 second (FEVj), FEVj/FVC ratio, and forced expiratory flows between 25% and 75% of vital capacity were assessed through ergo-spirometry. At the beginning of the ergo-spirometry, arterial oxygen saturation, respiratory rate, heart rate, blood pressure, tidal volume and the per ception of lower extremity fatigue and dyspnea were recorded using the modified Borg scale. The test lasted approximately 10 minutes. Results: The clinical records of 43 children collected from six health centers were reviewed. Out of these, 29 children met inclusion criteria, and 23 were re cruited. Two children were unable to participate, reducing the final subject group to 21 (13 males, 8 females). The mean age was 8.8 ± 2 years; weight 30.5 ± 10.9 kg; height 1.32 ± 0.11 m; and body mass index 17.1 ± 3.5 (z-score 0.01 ± 1.34). More than half of the children (61%) had normal weight. The obtained VO2peak was 43.7 ± 6.5 ml/min/kg (106.7 ± 19.8% of the predictive values). Only 10% of the children had values lower than those predicted by sex and age. No correlations were found between VO2peak and anthropometric and pulmonary function variables. Conclu sion: Most of the evaluated children (90%) had physical capacity similar to healthy subjects by sex and age.

Assuntos

Humanos , Masculino , Feminino , Criança , Aptidão Física/fisiologia , Fibrose Cística/fisiopatologia , Consumo de Oxigênio , Espirometria , Chile , Capacidade Vital , Volume Expiratório Forçado , Estudos Transversais , Teste de Esforço

RESUMO

BACKGROUND: Current therapies for heart failure (HF) are followed by strategies to improve quality of life and exercise tolerance, besides reducing morbidity and mortality. Some HF patients present changes in the musculoskeletal system and inspiratory muscle weakness, which may be restored by inspiratory muscle training, thus increasing respiratory muscle strength and endurance, maximal oxygen uptake (VO2), functional capacity, respiratory responses to exercise, and quality of life. Yoga therapies have been shown to improve quality of life, inflammatory markers, and peak VO2 mostly in HF patients with a reduced ejection fraction. However, the effect of different yoga breathing techniques in patients showing HF with a preserved ejection fraction (HFpEF) remain to be assessed. METHODS/DESIGN: A PROBE (prospective randomized open blinded end-point) parallel-group trial will be conducted at two specialized HF clinics. Adult patients previously diagnosed with HFpEF will be included. After signing informed consent and performing a pre-test intervention, patients will be randomized into three groups and provided with either (1) active yoga breathing techniques; (2) passive yoga breathing techniques (pranayama); or and (3) control (standard pharmacological treatment). Follow-up will last 8 weeks (16 sessions). The post-intervention tests will be performed at the end of the intervention period for analysis of outcomes. Interventions will occur continuously according to patients' enrollment. The main outcome is respiratory muscular resistance. A total of 33 enrolled patients are expected. The present protocol followed the SPIRIT guidelines and fulfilled the SPIRIT checklist. DISCUSSION: This trial is probably the first to assess the effects of a non-pharmacological intervention, namely yoga and specific breathing techniques, to improve cardiorespiratory function, autonomic system, and quality of life in patients with HFpEF. TRIAL REGISTRATION: REBEC Identifier: RBR-64mbnx (August 19, 2012). Clinical Trials Register: NCT03028168 . Registered on 16 January 2017).

Assuntos

Exercícios Respiratórios , Insuficiência Cardíaca/terapia , Pulmão/fisiopatologia , Volume Sistólico , Função Ventricular Esquerda , Yoga , Idoso , Brasil , Exercícios Respiratórios/efeitos adversos , Aptidão Cardiorrespiratória , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Consumo de Oxigênio , Estudos Prospectivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento

RESUMO

The aim of this study was to verify body composition, cardiorespiratory fitness, and biochemical markers of prepubertal overweight and obese boys to a 16-week futsal training program. Methods: Sixteen boys (age: 7-10 y, body mass index>thanat 95th percentileaccording to Center for Disease Control and Prevention; 35.5±7.4 percent fat) participated to futsal training program. The assessment of body composition was estimated using skinfold thickness, and the following variables were evaluated: total body mass, body mass index, body fat percentage, and lean body mass. Aerobic fitness measurementwas performed by gas exchange analysis in treadmill. In addition, an evaluation of the biochemical profile was conducted: triglycerides, total cholesterol, low density lipoprotein cholesterol, high-density lipoprotein cholesterol, plasma concentrations of glucose, and insulin. The futsal intervention included 60-min sessions performed two times/week. The mean intensity during training was between 57 to 88% of maximal heart rate of the age-predicted. Individual portable heart rate monitor controlled training intensity. Results: Significant increases in total body mass (4%), height (3%), lean body mass (8%), and significant 6%-decrease in body fat percentage was observed. Body mass index remained unchanged. Maximal oxygen uptake was elevated (p<0.018) by 11%. Biochemical markers were not modified after intervention. No association was found between body composition and metabolic variables. The effect size of futsal training on most variables was small (<0.5). Conclusion: Controlled intensity and adherence to this 16-week futsal training program were determinant to enhance body composition, and cardiorespiratory fitness in this group of prepubertal boys.(AU)

Assuntos

Humanos , Masculino , Criança , Consumo de Oxigênio/fisiologia , Futebol/fisiologia , Composição Corporal , Índice de Massa Corporal , Sobrepeso , Obesidade Infantil , Exercício Físico

RESUMO

OBJECTIVE: To determine running economy in a large sample of elite soccer and futsal players to obtain benchmarks in different positions. METHODS: Running Economy is the energy demand at a submaximal running velocity. Players were divided into 6 subgroups. Soccer: defenders, midfielders, and strikers; futsal: defenders, wingers, and pivots. Elite soccer players (n=129) and elite futsal players n=72 performed an incremental running test starting at 8.4 km.h-1 with increments of 1.2 km.h-1 every two minutes on a treadmill until exhaustion. Running Economy was determined by interpolation between ventilatory thresholds 1 and 2 (VT1 and VT2). RESULTS: Running Economy (measured as mL.kg-1.km-1) was compared between the playing positions in the two team sports. In soccer, running economy was 222.7 (defenders), 227.0 (midfielders), and 219.8 (strikers) mL.kg-1.km-1, respectively. In futsal, the corresponding values were 198.5 (defenders), 196.9 (wingers), and 190.5 (pivots) mL.kg-1.km-1, respectively. We no found significantly differences between the three positions in both sports. The Running Economy of futsal players was 12.5% better than that of soccer players. Running Economy correlated positively with oxygen uptake at VT2 in both sports and in all positions. CONCLUSION: Futsal players exhibited better Running Economy than soccer players; this should be considered as a factor in the athlete's training plan.

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OBJETIVO: Determinar a Economia de Corrida numa grande amostra de jogadores de futebol e futsal de elite em diferentes posições do campo. METODOS: Os jogadores foram subdivididos em três subgrupos: futebol (jogadores de defesa, meio-campistas e atacantes) e futsal (jogadores de defesa, alas e pivôs). Foram 129 jogadores de futebol e 72 jogadores de futsal, que competem nas respectivas primeiras divisões do Brasil. Os jogadores foram submetidos a teste de esforço em esteira (8,4 km-1.h+1,2km-1.h a cada dois minutos) até a exaustão. Consumo máximo de oxigênio, limiares ventilatórios e Economia de Corrida foram registrados por análise de troca gasosa respiratória. A Economia de Corrida foi determinada por interpolação utilizando as velocidades dos limiares ventilatórios 1 e 2 e o consume de oxigênio nas duas velocidades. RESULTADOS: Os valores de Economia de Corrida entre as posições nos dois esportes foram os seguintes: Futebol, jogadores de defesa (222,7±16,7mL.kg-1.km-1), meio-campistas (227±19,9mL.kg-1.km-1), e atacantes (219,8±17,2mL.kg-1.km-1). Futsal, jogadores de defesa (198,5±10,8mL.kg-1.km-1), alas (196,9±16,2mL.kg-1.km-1), e pivôs (190,5±11,8mL.kg-1.km-1). Não foram encontradas diferenças significativas entre as três posições em ambos os esportes. A Economia de Corrida dos jogadores de futsal foi 12,5% melhor do que dos jogadores de futebol. Neste estudo, os jogadores da posição pivô no futsal tiveram os melhores valores de Economia de Corrida (custo de oxigênio mais baixo). Embora o consumo máximo de oxigênio (VO2max) e o limiar ventilatório 2 (LV2) fosse maior nos jogadores de futebol, a Economia de Consumo foi pior. Esta correlacionou-se positivamente com o VO2 no LV2 em ambos os esportes e em todas as posições CONCLUSÃO: Futsal tem melhor Economia de Consumo do que futebol. O presente estudo aponta a importância dos índices Economia de Consumo no plano de treinamento físico dos atletas.

Assuntos

Humanos , Consumo de Oxigênio/fisiologia , Limiar Anaeróbio/fisiologia , Exercício Físico/fisiologia , Desempenho Atlético/fisiologia , Corrida , Futebol

RESUMO

OBJECTIVE: To verify the effect of an endurance exercise program in middle stages of Parkinson's disease. METHODS: The patients were two women and seven men with Parkinson's disease, aged 56 to 74 years, classified at Hoehn and Yahr stages 2 to 2.5. The study was designed as an open long-term pilot trial over three months of supervised treadmill exercise training. Cardiopulmonary exercise test evaluations were performed before the start of the study (test 1) and after three months (test 2). The main outcome measure was walking economy (i.e., the rate of oxygen consumption during gait) measured between VT1 and VT2 speeds and Oxygen consumption (VO2). RESULTS: No changes (p=0.551) were observed for maximal oxygen uptake (VO2max, 24.6 vs 23.6 mL.kg-1.min-1) between tests. The walking economy was 20% better (p<0.001) after three months of aerobic endurance training (266.7 vs 212.6 mL.kg-1.km-1, pre- vs. post-training); the Cohen's "d" effect size (ES) was 0.99, a very large effect. CONCLUSION: Evidence from this pilot study in individuals with Parkinson's disease suggests that gains in walking economy occurs with a treadmill-training program without gain in aerobic power, but which may positively reduce the energy expenditure of activities of daily living in these patients.

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OBJETIVO: Verificar o efeito de um programa de treinamento físico aeróbio em estágios intermediários da doença de Parkinson (PD). MÉTODOS: Os pacientes eram duas mulheres e sete homens com PD, com idade entre 56 e 74 anos, classificados como estágios Hoehn e Yahr 2 a 2,5. O estudo foi concebido como um ensaio piloto aberto de longo prazo durante três meses de treinamento supervisionado e realizado em esteira ergométrica. As avaliações da troca gasosa pelo teste de exercício cardiopulmonar foram realizadas antes do início do estudo (teste 1) e após três meses (teste 2). A determinação da economia de caminhada (taxa de consumo de oxigênio durante a marcha) foi medida entre as velocidades do primeiro e do segundo limiar (LV1 e LV2) e do consumo de oxigênio (VO2) entre as duas velocidades por interpolação. RESULTADOS: Não foram observadas alterações (P = 0,153) para o consumo máximo de oxigênio (VO2max: 26,7 vs. 24,2 mL.kg-1.min-1) após o período de intervenção. A economia de caminhada foi 23% maior (P <0,001) após três meses de treinamento físico aeróbio (273,4 vs. 209,4 mL.kg-1.km-1, ES = 0.99, muito alto). CONCLUSÃO: Evidências deste estudo piloto em indivíduos com DP sugerem que os ganhos na economia de caminhada podem ocorrer com um programa de treinamento de "endurance" aeróbica na esteira sem ganho na potência aeróbia, mas que positivamente pode reduzir o gasto de energia das atividades da vida diária nesses pacientes.

Assuntos

Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Doença de Parkinson/fisiopatologia , Caminhada/fisiologia , Treino Aeróbico , Consumo de Oxigênio , Calorimetria Indireta , Projetos Piloto , Estudos Longitudinais , Eletrocardiografia , Teste de Esforço , Frequência Cardíaca

RESUMO

NEW FINDINGS: What is the central question of this study? To the best of our knowledge, no studies have evaluated oxygen uptake, carbon dioxide production and exercise tolerance in rats that have undergone myocardial infarction classified by myocardial infarct (MI) size. What is the main finding and its importance? Oxygen uptake and exercise intolerance are MI size dependent, and classification based on MI size can distinguish rats with functional capacity impairment. Rats with a large MI (>40% of the left ventricle) might provide a good model for the testing of new therapies that have the potential to modify the variables of functional capacity. Oxygen uptake (V̇O2) and exercise tolerance in rats classified by myocardial infarct (MI) size are underexplored. The aim of this study was to evaluate V̇O2, carbon dioxide production (V̇CO2) and exercise tolerance in rats that had undergone myocardial infarction. Fourteen weeks after myocardial infarction or sham surgery, rats underwent an integrated approach to evaluation of left ventricular function and V̇O2/V̇O2V̇CO2V̇CO2, exercise tolerance and skeletal muscle weight. Based on determination of MI size, rats were assigned to sham-operated controls (Sham, n = 12), small myocardial infarction (SMI, n = 8) and large myocardial infarction (LMI, n = 5) groups. The LMI rats showed lower systolic (ejection fraction and fractional shortening) and diastolic (E/A ratio) left ventricular function compared with SMI. Maximal V̇O2 (∼24%, P < 0.05), V̇O2 reserve (∼30%, P < 0.05), time to exhaustion (∼36%, P < 0.05) and maximal velocity (∼30%, P < 0.05) were lower in LMI compared with sham-operated control animals, with no difference between SMI rats and sham-operated controls. Maximal V̇CO2 and respiratory exchange ratio showed no significant difference between MI rats and sham-operated control rats. The LMI rats demonstrated lower gastrocnemius weight (∼12%, P < 0.05) and soleus weight (∼19%, P = 0.07) compared with sham-operated control rats. Significant correlations between MI size, left ventricular end-diastolic pressure, right ventricle hypertrophy, pulmonary congestion, ejection fraction and fractional shortening with maximal V̇O2 and distance run were observed. Oxygen uptake and exercise intolerance are MI size dependent.

Assuntos

Tolerância ao Exercício , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/patologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Função Ventricular Esquerda , Animais , Dióxido de Carbono/metabolismo , Modelos Animais de Doenças , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Direita/etiologia , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/fisiopatologia , Masculino , Fadiga Muscular , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Consumo de Oxigênio , Edema Pulmonar/etiologia , Edema Pulmonar/patologia , Edema Pulmonar/fisiopatologia , Troca Gasosa Pulmonar , Ratos Wistar , Fatores de Tempo

RESUMO

This study was conducted to correlate and compare values for variables determined in indirect tests with the values determined directly in youth soccer players. The study subjects were 27 youth soccer players (age 16.77 ± 0.75 years; body mass 63.29 ± 7.37 kg; body height 174.14 ± 8.46 cm) playing in the basic categories of a first division team at the regional level of Brazilian soccer. Each subject was evaluated with the following tests: a) a treadmill test to directly determine values of VO2max and Vamax (Treadmill); b) an indirect Shuttle Run Test (SRT); c) an indirect Carminatti's test (TCar). VO2max showed significantly different values in the Treadmill and the SRT (59.21 ± 5.88 and 50.67 ± 3.58 ml⋅kg-1⋅min-1, respectively). Similarly, values obtained for VPeak in the treadmill test and for Vamax in TCar were different from values for SRT VPeak (15.01 ± 1.10, 14.92 ± 0.87 and 12.64 ± 0.62 km⋅h-1, respectively). A correlation analysis showed a moderate relationship between values for VPeak TCar and VO2max determined on a treadmill (r = 0.46) and Vamax determined on a treadmill (r = 0.54). The analysis also showed a high correlation between values of VO2max determined on the treadmill and VO2max evaluated in the SRT (r = 0.69), as well as VPeak determined in the SRT and VO2max tested on the treadmill (r = 0.71), as well as between VPeak determined in the SRT and VO2max evaluated on the treadmill (r = 0.77). We concluded that the SRT underestimated values of VO2max and Vamax. Additionally, VPeak TCar showed no difference compared to Vamax, although it did show a low correlation with it. In addition the SRT, even with high correlations, did not seem to be a great predictor of aerobic fitness in youth soccer players.

RESUMO

Background: Aim: To compare the concentration of secretory immunoglobulin-A (sIgA) in young adults with average or excellent aerobic capacity before and after a cardiopulmonary graded exercise test. Methods: Participants were nine apparently healthy physically active males (Mean age = 21.3 ± 2.1 yr.), randomly allocated in two groups based on their VO2max: a) average aerobic capacity (AEC, n = 5) or b) excellent aerobic capacity (EAC, n = 4). Participants performed the Bruce protocol to determine their aerobic capacity. The sIgA was measured before the test, immediately after the test and 60-, 120-, 240-, and 1440-min after the test. Results: Mixed factorial 2 x 6 ANOVA indicated no significant interactions between groups and measurements (p = 0.956), and main effect groups on sIgA (AEC = 85.4 ± 19.3 μg/mL vs. EAC = 79.2 ± 21.5 μg/mL, p = 0.836). Tukey's post hoc analysis revealed significant differences measurement obtained immediately after the test and between the initial measurement (p = 0.020), 60-min (p = 0.030), 240-min (p = 0.016), and 1440-min (p = 0.028) following the test. Conclusion: There is no change in sIgA kinetics depending on the aerobic capacity of the participants following an aerobic capacity cardiopulmonary graded exercise test.

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Introducción. Objetivo: Comparar la cinética en la concentración de inmunoglobulina A salival (IgAs) en adultos jóvenes con capacidad aeróbica promedio (n: 5) o excelente (n: 4) antes y después de una prueba de esfuerzo. Método: 9 adultos jóvenes (edad 21,3 ± 2,1), divididos de acuerdo su VO2máx, realizaron una prueba de esfuerzo mediante el protocolo de Bruce. La concentración de IgAs fue determinada mediante el Salimetrics IgA Kit®, evaluando inicial, inmediatamente finalizada la prueba, +60, +120, +240, +1.440 min. Resultados: La prueba ANOVA 2x6 mixta indicó que no existieron interacciones significativas entre grupos y mediciones (p = 0,956). Tampoco se encontró una diferencia significativa en la media de IgAs en los grupos (Promedio = 85,4 ± 19.3 μg/mL vs Excelente=79,2 ± 21.5 μg/mL, p = 0,836). Independientemente de las mediciones, el análisis post hoc de Tukey indicó que las diferencias se encontraron en la medición obtenida inmediatamente después de la prueba y entre la medición inicial (p: 0,020), la medición obtenida 60 min (p: 0,030), 240 min (p: 0,016) y 1.440 min (p = 0,028) posteriores a la prueba. Conclusión: Los datos encontrados sugieren que no hay un cambio en la concentración de IgAs a través del tiempo en función de la capacidad aeróbica de los participantes.

Assuntos

Humanos , Masculino , Adulto , Adulto Jovem , Resistência Física/fisiologia , Saliva/química , Imunoglobulina A Secretora/análise , Limiar Anaeróbio/fisiologia , Imunoglobulina A Secretora/metabolismo , Cinética , Distribuição Aleatória , Estudos Transversais , Teste de Esforço

RESUMO

This study analyzed the influence of a 4-week high-intensity interval training on the pacing strategy adopted by runners during a 5-km running trial. Sixteen male recreational long-distance runners were randomly assigned to a control group (CON, n=8) or a high-intensity interval training group (HIIT, n=8). The HIIT group performed high-intensity interval-training twice per week, while the CON group maintained their regular training program. Before and after the training period, the runners performed an incremental exercise test to exhaustion to measure the onset of blood lactate accumulation, maximal oxygen uptake (VO2max), and peak treadmill speed (PTS). A submaximal constant-speed test to measure the running economy (RE) and a 5-km running trial on an outdoor track to establish pacing strategy and performance were also done. During the 5-km running trial, the rating of perceived exertion (RPE) and time to cover the 5-km trial (T5) were registered. After the training period, there were significant improvements in the HIIT group of ∼7 and 5% for RE (P=0.012) and PTS (P=0.019), respectively. There was no significant difference between the groups for VO2max (P=0.495) or onset of blood lactate accumulation (P=0.101). No difference was found in the parameters measured during the 5-km trial before the training period between HIIT and CON (P>0.05). These findings suggest that 4 weeks of HIIT can improve some traditional physiological variables related to endurance performance (RE and PTS), but it does not alter the perception of effort, pacing strategy, or overall performance during a 5-km running trial.

Assuntos

Humanos , Masculino , Adulto , Adulto Jovem , Treinamento Intervalado de Alta Intensidade/métodos , Resistência Física/fisiologia , Esforço Físico/fisiologia , Corrida/fisiologia , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Ácido Láctico/sangue , Consumo de Oxigênio/fisiologia , Valores de Referência , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Fatores de Tempo

RESUMO

BACKGROUND AND OBJECTIVE: A simple, low-cost approach commonly used to objectively analyze the cardiorespiratory fitness of individuals with different health conditions is the six-minute walk test (6-MWT). Our objective was to develop peak aerobic power prediction using the six-minute walk test in healthy older men. METHODS: We measured body composition (body mass [BM], body mass index [BMI], fat percentage [FAT]) and peak aerobic power breath-by-breath during cardiopulmonary exercise testing (CPET [velocity, heart rate [HR] and VO2 at the anaerobic threshold and peak]) and a 6-MWT (distance [D], weight by distance [WxD], HR and oxygen consumption [VO2] at peak) in 76 healthy older men aged 65 to 80 years (69.1 ± 0.3 yrs-old). RESULTS: We observed significant correlations for VO2peak during the 6-MWT as a function of WxD (R = 0.75, P < 0.0005), BM (R = 0.56, P < 0.0005), D (R = 0.43, P = 0.0004) and maximum HR (R = 0.37, P = 0.001). Distance correlated significantly with FAT (R = -0.43, P = 0.005), BMI (R = -0.36, P = 0.021) and age (R = -0.31, P < 0.045), whereas WxD correlated with BM (R = 0.86, P<0.005).The inclusion of WxD increased the R2 from 0.65 to 0.74 and decreased the estimative error while yielding the following equation (R = 0.86, standard error of the estimate (SEE) = 182.1 mL•min-1, P < 0.0005) to predict VO2peak: VO2peak = 962.2 + (0.037 x WxD) + (8.565 x maximum HR). A non-exercise model was obtained by univariate regressions but not multiple regressions. The FAT (R = 0.43, SEE = 702.2 m, P < 0.005) yielded the best model for predicting distance, i.e., distance = 702.2 - (3.067 x FAT). CONCLUSION: Our prediction model seems to accurately estimate VO2peak in healthy older men primarily when WxD is considered.

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OBJETIVO: O teste de caminhada de seis minutos (TC6M) é uma estrategia simples e de baixo custo operacional que objetivamente mede a aptidão cardiorrespiratória de indivíduos com diferentes condições de saúde. Nosso objetivo foi desenvolver equações de predição da potência aeróbica em homens idosos saudáveis usando o TC6M. MÉTODOS: Foram medidos a composição corporal (massa corporal [MC], índice de massa corporal [BMI], porcentagem de gordura [%G]) e potência aeróbica de pico através de teste cardiopulmonar de exercício máximo (velocidade, frequência cardíaca [FC] e consumo de oxigênio [VO2] no limiar anaeróbico e no pico]) e através do TC6M (distancia [D], produto massa corporal x distância, FC e VO2de pico) em 76 idosos saudáveis com idade entre 65 e 80 anos (69.1 ± 0.3 anos). RESULTADOS: Foram observadas correlações significativas para VO2pico no TC6M em função do produto MCxD (R = 0,75, P < 0,0005), MC (R = 0,56, P < 0,0005), D (R = 0,43, P = 0,0004) e FC máxima (R = 0,37, P = 0,001). A correlacionou-se significativamente com %G (R = -0,43, P = 0,005), IMC (R = -0,36, P = 0,021) e idade (R = -0,31, P < 0,045), enquanto que a MCxD correlacionou-se com MC (R = 0,86, P < 0,005). A inclusão da MCxD aumentou o R 2 de 0,65 para 0,74 e diminuiu o erro padrão da estimativa (EPE) gerando a equação (R = 0,86, EPE = 182,1 mL·min-1, P < 0,0005) para a predição do VO2peak: VO2peak = 962,2 + (0,037 x MCxD) + (8,565 x FC máxima). Foi também gerado um modelo preditivo não dependente de exercício através de regressão univariada, mas não múltipla. A %G (R=0,43, EPE = 702,2 m, P < 0,005) gerou o melhor modelo para a predição da distancia, i.e., distancia = 702,2 - (3,067 x %G). CONCLUSÃO: Nossas modelos de predição parecem estimar precisamente o VO2pico de idosos saudáveis, especialmente quando a MCxD é considerada.

Assuntos

Humanos , Masculino , Idoso , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Teste de Caminhada/métodos , Aptidão Cardiorrespiratória/fisiologia

RESUMO

The syndrome of heart failure (HF) promotes central and peripheral dysfunctions that result in functional capacity decrease, leading to fatigue, dyspnea, and exercise intolerance. The use of light-emitting diode therapy (LEDT) has shown good results reducing fatigue and exercise intolerance, when applied on skeletal muscles before or after exercises. Thereby, the aim of this study was to compare the effects of LEDT on functional capacity, aerobic power, and hemodynamic function in HF rats. Male Wistar rats (230-260 g) were randomly allocated into three experimental groups: Sham (n = 6), Control-HF (n = 4), and LEDT-HF (n = 6). The animals were subjected to an exercise performance test (ET) with gas analysis coupled in a metabolic chamber for rats performed two times (6 and 14 weeks after myocardial infarction). On the day after the baseline aerobic capacity test, the animals were submitted during 8 weeks to the phototherapy protocol, five times/week, 60 s of irradiation, 6 J delivered per muscle group. Statistical analysis was performed by one- and two-way ANOVAs with repeated measures and Student-Newman-Keuls post hoc tests (p ≤ 0.05). Comparing the percentage difference (Δ) between baseline and the final ET, there was no significant difference for the VO2max variable considering all groups. However, Sham and LEDT-HF groups showed higher relative values than the Control-HF group, respectively, for distance covered (27.7 and 32.5 %), time of exercise test (17.7 and 20.5 %), and speed (13.6 and 12.2 %). In conclusion, LEDT was able to increase the functional capacity evaluated by distance covered, time, and speed of exercise in rats with HF.

Assuntos

Tolerância ao Exercício/efeitos da radiação , Insuficiência Cardíaca/radioterapia , Terapia com Luz de Baixa Intensidade/métodos , Músculo Esquelético/efeitos da radiação , Animais , Teste de Esforço , Masculino , Condicionamento Físico Animal , Distribuição Aleatória , Ratos , Ratos Wistar