Relationship between Indirect Measures of Aerobic and Muscle Power with Frequency Speed of Kick Test Multiple Performance in Taekwondo Athletes.

This study aimed to determine the relationship between indirect measures of aerobic power and muscular power with Frequency Speed of Kick Test performance using multiple sets (FSKTmult) in high-level taekwondo athletes. We used a known-group method to test differences in FSKTmult performance between two groups designated as lower and higher performance in both aerobic power and muscular power. In total, 42 international or national taekwondo athletes of both sexes performed the FSKTmult, Progressive Specific Taekwondo Test (PSTT), and countermovement jump (CMJ). Our results showed that average of the three CMJ was moderately correlated with FSKTmult performance (r=0.44); whereas PSTT and FSKTmult were highly correlated (r=0.83). Moreover, the groups formed by lower and higher performance of time to exhaustion in PSTT, as well as the average of CMJ were able to discriminate performance in the FSKTmult (p ≤0.05). The present study thus suggests that aerobic and muscle power are important for FSKTmult performance.

Similar Muscular Adaptations in Resistance Training Performed Two Versus Three Days Per Week.

The purpose of the present study was to compare changes in muscle strength and hypertrophy between volume-equated resistance training (RT) performed 2 versus 3 times per week in trained men. Thirty-six resistance-trained men were randomly assigned to one of the two experimental groups: a split-body training routine (SPLIT) with muscle groups trained twice per week (n = 18) over four weekly sessions, or a total-body routine (TOTAL), with muscle groups being trained three times per week (n = 18) over three weekly sessions. The training intervention lasted 10 weeks. Testing was carried out pre- and post-study to assess maximal muscular strength in the back squat and bench press, and hypertrophic adaptations were assessed by measuring muscle thickness of the elbow flexors, elbow extensors, and quadriceps femoris. Twenty-eight subjects completed the study. Significant pre-to-post intervention increases in upper and lower-body muscular strength occurred in both groups with no significant between-group differences. Furthermore, significant pre-to-post intervention increases in muscle size of the elbow extensors and quadriceps femoris occurred in both groups with no significant between-group differences. No significant pre-to-post changes were observed for the muscle size of elbow flexors both in the SPLIT or TOTAL group. In conclusion, a training frequency of 2 versus 3 days per week produces similar increases in muscular adaptations in trained men over a 10-week training period. Nonetheless, effect size differences favored SPLIT for all hypertrophy measures, indicating a potential benefit for training two versus three days a week when the goal is to maximize gains in muscle mass.

Effects of different intensities of resistance training with equated volume load on muscle strength and hypertrophy.

The present study investigated the effects of different intensities of resistance training (RT) on elbow flexion and leg press one-repetition maximum (1RM) and muscle cross-sectional area (CSA). Thirty men volunteered to participate in an RT programme, performed twice a week for 12 weeks. The study employed a within-subject design, in which one leg and arm trained at 20% 1RM (G20) and the contralateral limb was randomly assigned to one of the three conditions: 40% (G40); 60% (G60), and 80% 1RM (G80). The G20 started RT session with three sets to failure. After G20 training, the number of sets was adjusted for the other contralateral limb conditions with volume-matched. CSA and 1RM were assessed at pre, post-6 weeks, and post-12 weeks. There was time effect for CSA for the vastus lateralis (VL) (8.9%, 20.5%, 20.4%, and 19.5%) and elbow flexors (EF) (11.4%, 25.3%, 25.1%, and 25%) in G20, G40, G60, and G80, respectively (p > .05). G80 showed higher CSA than G20 for VL (19.5% vs. 8.9%) and EF (25% vs. 11.4%) at post-12 weeks (p < .05). There was time effect for elbow flexion and unilateral leg press strength for all groups post-12 weeks (p < .05). However, the magnitude of increase was higher in G60 and G80. In conclusion, when low to high intensities of RT are performed with volume-matched, all intensities were effective for increasing muscle strength and size; however, 20% 1RM was suboptimal in this regard, and only the heavier RT intensity (80% 1RM) was shown superior for increasing strength and CSA compared to low intensities.

Efeito da ordem dos exercícios de força sobre o volume, o lactato e o desempenho / Effect of the order of strength exercises on volume, lactate and performance / Efecto de la orden de los ejercicios de fuerza en el volumen, lactato y rendimiento

RESUMO Introdução: A alternância entre segmentos corporais para prescrição do treinamento de força (TF) é amplamente utilizada, entretanto seus efeitos permanecem desconhecidos. Objetivo: Verificar o efeito agudo da manipulação da ordem dos exercícios do TF, alternando segmentos corporais, sobre a força dinâmica máxima (1 RM) de membros inferiores (MMII) e superiores (MMSS), a concentração de lactato sanguíneo [La], a percepção subjetiva de esforço (PSE) e o volume total de treino (VT). Métodos: Dezoito homens (23,1 ± 3,8 anos; 78,4 ± 8,6 kg; 1,72 ± 0,06 m) executaram três condições de TF: condição A (supino reto, desenvolvimento, rosca Scott, meio-agachamento, leg press, cadeira extensora); condição B (meio-agachamento, leg press, cadeira extensora, supino reto, desenvolvimento, rosca Scott) e condição C (supino reto, meio-agachamento, desenvolvimento, leg press, rosca Scott e cadeira extensora). Os exercícios foram executados com três séries de 10 RM. Os testes de 1 RM para MMII e MMSS foram realizados nas semanas iniciais e após as condições experimentais. As coletas de sangue foram feitas no repouso [T0], imediatamente após [IA], 3 [T3] e 5 minutos [T5] após cada condição. A PSE de MMSS, MMII e geral, e o VT foram mensurados ao final de cada condição. Resultados: A 1 RM foi reduzida depois da sessão em todas as condições tanto para MMSS (A = -19,4%; B = -23,0%; C = -22,8%) quanto para MMII (A = -16,2%; B = -15,3%; C = -16,1%) sem diferença entre condições. A PSE apresentou resultados similares entre as condições (Condição A = 8,4; Condição B = 8,7; Condição C = 8,7). Houve aumento significante no La no momento T3 da condição C comparado com as outras condições: (C = 7,29 mmol.L-1; A = 6,60 mmol.L -1; B = 6,51 mmol.L-1) (p < 0,0001). O VT na condição C (16.169,4 ± 2.562,5 kg) foi superior às condições A (13.222,2 ± 2.010,4 kg) e B (13.989,8 ± 2.223,4 kg) (p < 0,0001). Conclusão: Os resultados sugerem que somente o VT e a demanda metabólica foram mais afetados pela ordem dos exercícios.

ABSTRACT Introduction: The alternation between body segments for prescription of strength training (ST) is widely used; however, its effects remain unknown. Objective: To verify the acute effect of the manipulation of the order of ST exercises, alterna-ting body segments, on the maximum dynamic force (1 RM) of lower limbs (LL) and upper limbs (UL), blood lactate [La] concentration, subjective perception of effort (SPE) and the total training volume (TV). Methods: Eighteen men (23.1±3.8 years; 78.4±8.6 kg; 1.72±0.06 m) performed three ST conditions: condition A: (bench press, shoulder press, preacher arm curl, half squat, leg press, leg extension); condition B (half squat, leg press, leg extension, bench press, shoulder press, preacher arm curl) and condition C (bench press, half squat, shoulder press, leg press, preacher arm curl, leg extension). The exercises were performed in three sets of 10 RM. The 1 RM tests for LL and UL were performed in the initial weeks and after the experimental conditions. Blood samples were taken at rest [T0], immediately after [IA], 3 [T3], and 5 minutes [T5] after each condition. SPE of UL, LL, and general, and VT were measured at the end of each condition. Results: The 1 RM was reduced after the session in all conditions for both UL (A = -19.4%, B = -23.0%, C = -22.8%) and LL (A = -16.2 %, B = -15.3%, C = -16.1%) with no difference between conditions. The SPE presented similar results between the conditions (Condition A=8.4, Condition B=8.7, Condition C=8.7). There was a significant increase in La at time T3 of condition C compared to the other conditions: (C=7.29 mmol.L-1, A=6.60 mmol.L-1, B=6.51 mmol.L-1) (p<0.0001). The TV in condition C (16,169.4 ± 2,562.5 kg) was higher than conditions A (13,222.2 ± 2,010.4 kg) and B (13,989.8 ± 2223.4 kg) (p<0.0001). Conclusion: The results suggest that only TV and the metabolic demand were more affected by the order of exercises.

RESUMEN Introducción: La alternancia entre los segmentos del cuerpo para la prescripción de entrenamiento de fuerza (EF) es ampliamente utilizada, pero siguen desconocidos sus efectos. Objetivo: Evaluar el efecto agudo de la manipulación de la orden de los ejercicios de EF, alternando segmentos del cuerpo, en la fuerza máxima (1 RM) de las extremidades inferiores (EI) y superiores (ES), la concentración del lactato (La) en la sangre, la percepción subjetiva del esfuerzo (PSE) y el volumen de entrenamiento (VE). Métodos: Dieciocho hombres (23,1 ± 3,8 años; 78,4 ± 8,6 kg; 1,72 ± 0,06 m) realizaron tres condiciones de EF: Condición A (press de banca, press de hombros, rosca Scott, media sentadilla, prensa de piernas, extensión de la pierna); Condición B (media sentadilla, prensa de piernas, extensión de la pierna, press de banca, press de ombros, rosca Scott) y Condición C (press de banca, media sentadilla, press de hombros, prensa de piernas, rosca Scott, y extensión de la pierna). Los ejercicios se realizaron con tres series de 10 RM. Las pruebas de 1 RM de las EI y ES se llevaron a cabo en las primeras semanas y después de las condiciones experimentales. Las muestras de sangre fueron tomadas en reposo [T0] inmediatamente después [IA], 3 [T3] y 5 minutos [T5] después de cada condición. La PSE, de ES, EI y general y VE se midieron al final de cada condición. Resultados: La 1 RM se redujo después de la sesión en todas las condiciones para ES (A = -19,4%; B = -23,0%; C = -22,8%) y EI (A = -16,2%; B = -15,3%; C = -16,1%), sin diferencia entre las condiciones. La PSE mostró resultados similares entre las condiciones (Condición A = 8,4, Condición B = 8.7, Condición C = 8,7). Hubo un aumento significativo en La en el momento T3 de la condición C en comparación con las otras condiciones (C = 7,29 mmol.L-1; A = 6,60 mmol.L-1, B = 6,51 mmol.L-1) (p < 0,0001). El VE en la condición C (16.169,4 ± 2.562,5 kg) fue superior a las condiciones A (13.222,2 ± 2.010.4 kg) y B (13.989,8 ± 2.223,4 kg) (p < 0,0001). Conclusión: Los resultados sugieren que solamente el VE y las demandas metabólicas fueron afectados por el orden de los ejercicios.

Effects of different strength training frequencies during reduced training period on strength and muscle cross-sectional area.

This study investigated the effects of different reduced strength training (RST) frequencies on half-squat 1 RM and quadriceps cross-sectional area (QCSA). Thirty-three untrained males (24.7 ± 3.9 years; 1.73 ± 0.08 m; 74.6 ± 8.4 kg) underwent a 16-week experimental period (i.e. eight weeks of strength training [ST] followed by additional eight weeks of RST). During the ST period, the participants performed 3-4 sets of 6-12 RM, three sessions/week in half-squat and knee extension exercises. Following ST, the participants were randomly allocated to one of three groups: reduced strength training with one (RST1) or two sessions per week (RST2), and ceased training (CT). Both RST1 and RST2 groups had their training frequency and total training volume-load (i.e. RST1 = 50.3% and RST2 = 57.1%) reduced, while the CT group stopped training completely. Half-squat 1 RM (RST1 = 27.9%; RST2 = 26.7%; and CT = 28.4%) and QCSA (RST1 = 6.1%; RST2 = 6.9%; and CT = 5.8%) increased significantly (p < .05) in all groups after eight weeks of ST. No significant changes were observed in 1 RM and QCSA for RST1 and RST2 groups after the RST period, while the CT group demonstrated a decrease in half-squat 1 RM (22.6%) and QCSA (5.4%) when compared to the ST period (p < .05). In conclusion, different RST frequencies applied were able to maintain muscle mass and strength performance obtained over the regular ST period. Thus, it appears that RST frequency does not affect the maintenance of muscle mass and strength in untrained males, as long as volume-load is equated between frequencies.

DESEMPENHO DE INDIVÍDUOS COM DERMOPIGMENTAÇÃO SUBMETIDOS À PRÁTICA DE EXERCÍCIO FÍSICO / PERFORMANCE OF DERMAL PIGMENTED INDIVIDUALS SUBMITTED TO PHYSICAL EXERCISE / DESEMPEÑO DE INDIVIDUOS CON DERMOPIGMENTACIÓN SOMETIDOS A PRÁCTICA DE EJERCICIOS FÍSICOS

RESUMO Introdução: A duração e a intensidade dos exercícios provocam diferentes alterações no sistema imunológico, dentre elas a diminuição das respostas imunes, acarretando queda no desempenho físico. Sabe-se também que a dermopigmentação pode colaborar com tais alterações no comportamento deste sistema. Objetivo: Avaliar os efeitos da dermopigmentação sobre o desempenho no exercício físico. Método: Neste ensaio clínico participaram 12 sujeitos, dentre eles seis com dermopigmentação, idade (anos), peso (Kg), estatura (cm) e gordura corporal (%) de 16,5 ± 1,16; 68,10 ± 6,83; 176,29 ± 7,71; 11,49 ± 0,58 respectivamente, divididos em dois grupos, sendo submetidos a teste de esforço máximo com intensidade progressiva em esteira ergométrica para determinação do consumo máximo de oxigênio (VO2máx), limiares anaeróbios (LAns) e economia de corrida (EC 14km/h %), sendo realizadas coletas de lactato pré e 5 minutos pós-teste. Os dados foram tratados por "teste t" para variáveis independentes, tendo como nível de significância adotado α < 0,05. Resultados: Foram observadas diferenças significativas entre os grupos em relação à concentração sanguínea de lactato (CSL) pré-teste (4,6 ± 0,11 e 3,23 ± 0,88 para dermopigmentados e não dermopigmentados, respectivamente; p < 0,05) e 5 minutos pós-teste (5,65 ± 0,49 e 13,13 ± 2,20 para dermopigmentados e não dermopigmentados, respectivamente; p < 0,05). O tempo de teste também foi significativamente superior para o grupo não dermopigmentado em comparação ao grupo com dermopigmentação (8 min 47 seg ± 0,08 e 7 min 39 seg ± 0,03 respectivamente; p < 0,05), bem como análise do WURSS-21 (3,33 ± 3,14 e 2,00 ± 1,09, respectivamente; p > 0,05). Em relação às demais variáveis dependentes (VO2máx, segundo limiar anaeróbio e economia de corrida) não foram encontradas diferenças estatisticamente significativas. Conclusão: A dermopigmentação produziu rendimento inferior no teste de esforço máximo, influenciando o desempenho no exercício físico.

ABSTRACT Introduction: Duration and intensity of exercises cause different alterations in the immunity system, among them, reduction of immunity responses, causing decrease in physical performance. It is also known that dermal pigmentation can influence such alterations in the system's behavior. Objective: To evaluate the effects of dermal pigmentation on performance of physical exercise. Method: In this clinical essay, 12 subjects participated, among them, 6 with dermal pigmentation, being age (years), weight (kg), height (cm) and body fat (%) measured as 16.5 ± 1.16; 68.10 ± 6.83; 176.29 ± 7.71; 11.49 ± 0.58, respectively, divided in two groups. They were submitted to a maximum effort test with gradual intensity in treadmill to determine maximum oxygen consumption (VO2max), anaerobic thresholds (AnT) and running economy (RE 14km/h %), lactate being collected before and 5 minutes after test. Data has been analyzed by "t test" for independent variables, having a level of significance of α < 0.05. Results: Significant differences were observed between groups in relation to pre-test blood lactate concentration (BLC) (4.6 ± 0.11 and 3.23 ± 0.88 for the dermal pigmented and non-dermal pigmented groups, respectively; p <0.05) and 5 minutes post-test (5.65 ± 0.49 and 13.13 ± 2.20 for the dermal pigmented and non-dermal pigmented groups, respectively; p <0.05). The testing time was also significantly higher for the non-dermal pigmented group, compared to the dermal pigmented group (8 min 47 sec ± 0.08 and 7 min 39 sec ± 0.03 respectively; p < 0.05) and also analysis of WURSS-21 (3.33 ± 3.14 and 2.00 ± 1.09, respectively; p> 0.05). In relation to the other dependent variables (VO2max, second anaerobic threshold and running economy) no statistically significant differences were found. Conclusion: Dermal pigmentation produced lower performance in the maximum effort test, with an influence on performance of physical exercise.

RESUMEN Introducción: La duración e intensidad del ejercicio provocan diferentes cambios en el sistema inmunológico, entre ellos, la reducción de las respuestas inmunes, lo que resulta en disminución en el rendimiento físico. También se sabe que la dermopigmentación puede colaborar con tales cambios en el comportamiento de este sistema. Objetivo: Evaluar los efectos de dermopigmentación en el rendimiento del ejercicio físico. Método: En este ensayo clínico participaron 12 sujetos, entre ellos seis con dermopigmentación, con edad (años), peso (kg), altura (cm) y grasa corporal (%) de 16,5 ± 1,16; 68,10 ± 6,83; 176,29 ± 7,71; 11,49 ± 0,58, respectivamente, divididos en dos grupos. Estos se sometieron a la prueba de esfuerzo máximo con intensidad progresiva en una cinta ergométrica para determinar el consumo máximo de oxígeno (VO2máx), umbrales anaeróbicos (UA) y la economía de carrera (EC 14km/h %), con colecciones de lactato pre y 5 minutos después de la prueba. Los datos fueron analizados por "prueba t" para las variables independientes, teniendo un nivel de significación adoptado de α < 0,05. Resultados: Se observaron diferencias significativas entre los grupos con respecto a la concentración de lactato en sangre (CLS) pre-test (4,6 ± 0,11 y 3,23 ± 0,88 para dermopigmentados y no dermopigmentados, respectivamente; p < 0,05) y 5 minutos después de la prueba (5,65 ± 0,49 y 13,13 ± 2,20 para dermopigmentados no dermopigmentados, respectivamente; p < 0,05). El tiempo de prueba fue también significativamente mayor para el grupo no dermopigmentado en comparación con el grupo con dermopigmentación (8 min 47 seg ± 0,08 y 7 min 39 seg ± 0,03, respectivamente; p <0,05) y WURSS-21 análisis (3,33 ± 3,14 y 2,00 ± 1,09 respectivamente; p> 0,05). En cuanto las demás variables dependientes (VO2máx, segundo umbral anaeróbico y economía de carrera) no se encontraron diferencias estadísticamente significativas. Conclusión: La dermopigmentación produjo bajo rendimiento en la prueba de esfuerzo máximo, que influye en el rendimiento del ejercicio físico.

Influência do nível de força máxima na produção e manutenção da potência muscular / Influence of maximum strength on muscle power production and endurance

Indivíduos mais fortes (com nível mais elevado de força máxima, Fmax) demonstram menor resistência de força que indivíduos mais fracos (com nível mais baixo de Fmax) em uma mesma intensidade relativa. Como o nível de Fmax influencia a produção de potência, espera-se que sujeitos mais fortes também apresentem uma menor resistência de potência. O objetivo deste estudo foi avaliar a influência do nível de Fmax na produção e na resistência de potência durante repetições e séries múltiplas do exercício meio-agachamento. Quarenta e dois sujeitos foram classificados de acordo com o resultado no teste de força dinâmica máxima (1RM) e destes os 10 mais fortes e os 10 mais fracos foram selecionados para participar no estudo. Para avaliar a resistência de potência os dois grupos realizaram 10 séries de seis repetições a 40 por cento e a 60 por cento 1RM na maior velocidade possível. A potência absoluta (PA) e a potência relativa ao peso corporal (PR) desenvolvidas na fase concêntrica do exercício foram medidas. A análise de variância (ANOVA two-way) revelou que os sujeitos mais fortes diminuíram a PA a 60 por cento 1RM a partir da quarta repetição e a PR a partir da quinta repetição. Já os sujeitos mais fracos diminuíram a PA apenas na sexta repetição e mantiveram o rendimento na PR ao longo das 10 séries. Não houve efeito significante na intensidade de 40 por cento 1RM. Isso sugere que sujeitos mais fortes fadigam antes em maiores intensidades de carga. Essa fadiga precoce nos sujeitos mais fortes poderia estar ligada a diferentes fatores associados ao controle da homeostase orgânica como o comportamento da pressão arterial, da atividade eletromiográfica e a proporção de fibras musculares dos tipos I e II.

It seems that stronger subjects present less strength endurance compared to weaker subjects at the same relative intensity. Since the level of maximum strength affects power production, it is also expected that stronger subjects present lower power endurance. The aim of this study was to evaluate the effects of maximum strength on power production and endurance over multiple sets and repetitions of the half-squat exercise. Forty- two subjects were classified according to the result in the 1RM test and the 10 strongest and 10 weakest were selected to participate. In order to evaluate power endurance, both groups performed 10 sets of 6 repetitions at 40 percent and 60 percent 1RM as fast as possible. The absolute power (AP) and relative power (RP) (corrected by body weight) developed in half-squat concentric phase were measured. Analysis of variance for repeated measures (Two-Way ANOVA) revealed that the stronger subjects decreased AP from 4th repetition on and RP from 5th repetition on at 60 percent 1RM. The weakest subjects decreased AP from 6th repetition on and maintained RP production over the ten series. There was no significant effect on 40 percent 1RM. This result suggests that stronger subjects fatigue first at higher intensities. The early fatigue in stronger subjects could be associated with different factors related to body control of homeostasis such as blood pressure, motor units recruitment and proportion of types I and II muscle fibers.