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Respiratory muscle training (RMT) improves physical performance, although it is still debated whether this effect depends on the type of training. The purpose of this study was to compare the effects of two different types of RMT, i.e., voluntary isocapnic hyperpnea (VIH) and inspiratory threshold loading (ITL), on the deoxygenation of intercostal (ΔSmO2-m. intercostales) and vastus lateralis (ΔSmO2-m. vastus lateralis) muscles during exercise. Twenty-four participants performed eight weeks of RMT by: (i) VIH (3 days·week-1 for 12 min at 60% maximal voluntary ventilation) or (ii) ITL (5 sets·week-1 of 30 breaths·minute-1 at 60% maximal inspiratory pressure). Cardiopulmonary exercise testing (CPET) included ΔSmO2 (the change from baseline to end of test) of intercostal and vastus lateralis muscles. After RMT, both groups showed decreased ΔSmO2-m. intercostales (VIH = 12.8 ± 14.6%, p = 0.04 (effect size, ES = 0.59), and ITL = 8.4 ± 9.8%, p = 0.04 (ES = 0.48)), without a coincident change of ∆SmO2-m. vastus lateralis. ITL training induced higher VËO2-peak absolute values than VIH (mean Δ post-pre, ITL = 229 ± 254 mL·min-1 [95% CI 67-391] vs. VIH, 39 ± 153 mL·min-1 [95% CI -58-136.0], p = 0.01). In conclusion, both RMT improved the balance between supply and oxygen consumption levels of m. intercostales during CPET, with ITL also inducing an increase of aerobic capacity.
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We examined the effects of different small-sided games (SSG) configurations on heart rate (HR), rating of perceived exertion (RPE), and running demands in soccer players. Twelve male soccer players (U18) participated in this randomized cross-over study. Players performed three SSG in different "fixed" and "dynamic" pitch sizes (3v3 in large (SSGL) and small (SSGS) fixed area; or 3v3 in dynamic dimensions [SSGD]), with 4x4 minutes interspersed by 2 minutes of rest. HR measures (maximum [HRmax], average [HRavg], and percentage of maximum [%HRmax]), RPE, and running demands were collected across the SGG sessions. The following running activities were recorded: total distance covered (TD), distance covered (DC) at 6-12 km·h-1, ≥ 12-18 km·h-1, and >18 km·h-1, peak running speed, acceleration (ACC) and deceleration (DEC) at 1-2 m·s-2 and 2-3 m·s-2, player load, and high metabolic load distance (HMLD). SSGL displayed higher HRavg, %HRmax, and RPE values than SSGS (p < 0.05). SSGL resulted in higher TD, DC at 6-12 km·h-1, ≥ 12-18 km·h-1, > 18 km·h-1, and higher peak speed than SSGS and SSGD (p < 0.05). Moreover, SSGD presented higher TD and DC at 6-12 km·h-1 and ≥ 12-18 km·h-1 than SSGS (p < 0.05). In contrast, SSGD and SSGS showed higher number of ACC and DEC at 1-2 m·s-2 than SSGL (p < 0.05). In conclusion, the pitch size and playing area of the SSG can be manipulated to promote desired physiological and physical demands in young soccer players.HighlightsWe examined how fixed (small and large) or variable (dynamic) pitch sizes affected the psychophysiological and running demands of young soccer players during small-sided games.Small-sided games with larger pitch sizes and areas per player elicited greater psychophysiological and running demands than small areas.The pitch size designed in the current study does not appear to affect the number of acceleration and deceleration (> 2 m·s-2).Varying the pitch size during the small-sided games (i.e. dynamic condition) could be an interesting constraint to be considered by soccer coaches in order to enhance task variability.
Assuntos
Desempenho Atlético , Frequência Cardíaca , Esforço Físico , Corrida , Futebol , Humanos , Masculino , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Frequência Cardíaca/fisiologia , Esforço Físico/fisiologia , Corrida/fisiologia , Corrida/psicologia , Futebol/fisiologia , Futebol/psicologia , Estudos Cross-OverRESUMO
This investigation demonstrated a routine of evaluation and training of an athlete of the SL3 class of parabadminton for 2 days continuously monitored by a metabolic analyzer with measurements of oxygen consumption (VÌO2), carbon dioxide production, and heart rate (HR). The results showed HR and VÌO2 responses varying between 50% and 99.54% of HRmax (mean HR 80.92 bpm), and 6% and 104% (mean VÌO2 35.25 mL/kg/min) of VÌO2max, during the simulated game. The exercise test and the simulated training session showed significant changes in HR and VÌO2, reinforcing the need for considerable energy input to training and assessment.
Assuntos
Metabolismo Energético , Consumo de Oxigênio , Atletas , Metabolismo Energético/fisiologia , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Humanos , Oxigênio , Consumo de Oxigênio/fisiologiaRESUMO
Purpose: The aim of the study was to investigate the effect of linear and undulating strength-power training scheme on the repeated sprint ability (RSA) and lower body strength of soccer players. Method: Twenty soccer players (under-20 category) were split into 2 groups: the linear load (LL, n=10) and the undulating load (UL, n=10). In the commencement and at the end of the 6-week pre-season period, the RSA test (6 x 35m) and the 1RM parallel squat test (1RMsquat) were conducted. The LL and UL performed the same type and number of sessions. The training stimulus in the strength training was different between LL (Weeks 1 and 2 = Muscular Endurance; Weeks 3 and 4 = Strength; Weeks 5 and 6 = Power) and UL (daily load variation in the same week). Results: A improvement in RSAmean and 1RMsquat was detected in LL and in UL. No significant difference was noted between LL vs UL for all variables. Conclusion: Both groups improved maximal muscle strength in parallel back squat and RSA. UL induced a greater gain in RSA.(AU)
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Humanos , Masculino , Adolescente , Adulto , Futebol/fisiologia , Desempenho Atlético/fisiologia , /métodos , Corrida/fisiologia , Testes Respiratórios/métodos , Antropometria/métodos , Força Muscular/fisiologiaRESUMO
The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size.
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The aim of this study was to evaluate the acute effects of unilateral ankle plantar flexors static-stretching (SS) on the passive range of movement (ROM) of the stretched limb, surface electromyography (sEMG) and single-leg bounce drop jump (SBDJ) performance measures of the ipsilateral stretched and contralateral non-stretched lower limbs. Seventeen young men (24 ± 5 years) performed SBDJ before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch) unilateral ankle plantar flexor SS (6 sets of 45s/15s, 70-90% point of discomfort). SBDJ performance measures included jump height, impulse, time to reach peak force, contact time as well as the sEMG integral (IEMG) and pre-activation (IEMGpre-activation) of the gastrocnemius lateralis. Ankle dorsiflexion passive ROM increased in the stretched limb after the SS (pre-test: 21 ± 4° and post-test: 26.5 ± 5°, p < 0.001). Post-stretching decreases were observed with peak force (p = 0.029), IEMG (P<0.001), and IEMGpre-activation (p = 0.015) in the stretched limb; as well as impulse (p = 0.03), and jump height (p = 0.032) in the non-stretched limb. In conclusion, SS effectively increased passive ankle ROM of the stretched limb, and transiently (less than 10 minutes) decreased muscle peak force and pre-activation. The decrease of jump height and impulse for the non-stretched limb suggests a SS-induced central nervous system inhibitory effect. Key pointsWhen considering whether or not to SS prior to athletic activities, one must consider the potential positive effects of increased ankle dorsiflexion motion with the potential deleterious effects of power and muscle activity during a simple jumping task or as part of the rehabilitation process.Since decreased jump performance measures can persist for 10 minutes in the stretched leg, the timing of SS prior to performance must be taken into consideration.Athletes, fitness enthusiasts and therapists should also keep in mind that SS one limb has generalized effects upon contralateral limbs as well.
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The main goal of this study was to assess the appropriateness of both ergometric and modified hurdles tests for an annual cycle of hurdlers who were working on mastering the 400 m distance. Nine Polish hurdlers (personal best: 54.46±2.16 s, age: 20.67±1.87 years) were chosen as the research participants. In each of two mastering periods in the research, an ergometric test and a specific test were implemented during a hurdle run. In February, an interval ergometric test (5×6 s) and an interval hurdle test (IHT) were performed. Additionally, in May, a classic Wingate test and a 200 m hurdle run were introduced. With regard to the ergometric tests, we assessed the following measurements: maximum power (Pmax) and mean power (P×) reached in five repetitions as well as total work (Wtotal) performed in five attempts. The Mann-Whitney test was used to distinguish between the athletic test results obtained in the preparation period outlined above and those obtained in the first period. Lactate (LA) concentrations were assessed with the Chi-square test. Moreover, Spearman's rank correlation coefficients were used in the analysis. The achieved study results indicate the lack of significant differentiation of the ergometric test parameters (p≥ 0.05). The spatial structure of both specific tests (5×2 H v. 200 m H) was similar given that the first and the second parts of both hurdle races and the number of steps taken were similar. The basic parameters of the ergometric tests did not exhibit any relationship with the recommended record time achieved for the 400 m hurdle run.
O objetivo deste estudo foi avaliar a idoneidade de seleção dos testes ergométricos e testes modificados de corridas com barreiras ao longo do ciclo anual de treinamento dos atletas na distância de 400m. Participaram do estudo nove atletas poloneses (melhor resultado: 54,46±2,16s, idade: 20,67±1.87 anos). Em duas temporadas de treinamento foram realizados dois testes: ergométrico e especial (=na corrida com barreiras). Em fevereiro foi efetuado o teste ergonómico em intervalos (95x6s) e o teste com barreiras Rest com intervalos (IHT). Em maio foi efetuado o teste clássico de 30 s Wingate e uma corrida de 200m com barreiras (200mH). Nas corridas com barreiras foram considerados os parâmetros de tempo, potência máxima (Pmax), potência média (Px) e trabalho total (Wtotal). Para avaliar as diferenças entre os resultados dos testes numa temporada foi aplicado o teste de Mann-Whithney. As diferenças de concentração do lactato (LA) foram avaliadas com o teste Chi-square. Na análise foram considerados também os coeficientes de correlação de postos de Spearman. Os resultados dos estudos demostram a ausência de diferenças pertinentes nos parâmetros dos testes ergométricos (p ≥ 0,05). A estrutura espacial de ambos os testes especiais (5x2H vs. 200mH) foi semelhante: na primeira e segunda parte de ambas as corridas foi efetuado o número parecido dos passos. Os parâmetros essenciais dos testes ergométricos (Pmax, Px, Wtotal) não demostraram relações importantes com o resultado recorde na corrida de 400m com barreiras. A análise demostrou a possibilidade de utilização seletiva dos testes ergométricos na avaliação do grau de preparação dos atletas para a distância de 400m com barreiras.
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Este estudio tuvo como propósito intervenir en la conducta de evitación experiencial, evidenciada en tres tenistas de 16 y 17 años, a través de la Terapia de Aceptación y Compromiso. Se evaluó la evitación experiencial mediante dos instrumentos. El primero es el registro de dicha conducta exhibida por cada participante, el segundo es el Cuestionario de Aceptación - Acción adaptado al español y revisado por un filólogo. La intervención constó de cuatro sesiones. Para la medición por registros en el pretest y postest se programaron dos torneos en los cuales cada jugador compitió en tres ocasiones. Los resultados muestran un decremento en la frecuencia de la conducta de evitación experiencial, sin embargo, la disminución en los puntajes en el cuestionario no es proporcional entre los dos jugadores que participaron en la totalidad de la investigación.
The purpose of this study was to intervene in the behavior of experiential avoidance evidenced in three tennis players ages 16 and 17 by means of Acceptance and Commitment Therapy (ACT). The experiential avoidance was measured through two instruments. The first was through recognition of behavior exhibited by each participant, and the second was through the Acceptance Questionnaire - Action (AAQ) adapted to Spanish and revised by a philologist. The intervention consisted of four sessions. For measuring the registrations in the pretest and posttest, two tournaments were designed in which each player competed on three occasions. The results demonstrate a significant decrease in the frequency of the behavior of experiential avoidance. However, the decrease in the score of the AAQ is not proportional in the two tennis players that participed in the entirety of the investigation.