Non-uniform excitation of pectoralis major induced by changes in bench press inclination leads to uneven variations in the cross-sectional area measured by panoramic ultrasonography.

This study combined surface electromyography with panoramic ultrasound imaging to investigate whether non-uniform excitation could lead to acute localized variations in cross-sectional area and muscle thickness of the clavicular and sternocostal heads of pectoralis major (PM). Bipolar surface electromyograms (EMGs) were acquired from both PM heads, while 13 men performed four sets of the flat and 45° inclined bench press exercises. Before and immediately after exercise, panoramic ultrasound images were collected transversely to the fibers. Normalized root mean square (RMS) amplitude and variations in the cross-sectional area and muscle thickness were calculated separately for each PM head. For all sets of the inclined bench press, the normalized RMS amplitude was greater for the clavicular head than the sternocostal head (P < 0.001), and the opposite was observed during the flat bench press (P < 0.001). Similarly, while greater increases in cross-sectional area were observed in the clavicular than in the sternocostal head after the inclined bench press (P < 0.001), greater increases were quantified in the sternocostal than in the clavicular head after the flat bench press exercise (P = 0.046). Therefore, our results suggest that the PM regional excitation induced by changes in bench press inclination leads to acute, uneven responses of muscle architecture following the exercise.

Cardiorespiratory fitness and muscular strength of deaf futsal players.

The present study compared the cardiopulmonary exercise capacity and peak torque of the knee extensor and flexor muscles in team players associated with the Gaucho Deaf Futsal Federation players to those of their hearing peers. In this cross-sectional study, 16 male athletes, eight futsal players with hearing impairment (deaf group, DG; 22.6±7.7 years), and eight futsal players with normal hearing (control group, CG; 22.5±2.9 years) underwent a cardiopulmonary test on a treadmill and isokinetic dynamometry at 60°/sec. All athletes were subjected to a cardiopulmonary test on a treadmill and isokinetic dynamometry at 60°/sec. The main results showed a reduction in the cardiorespiratory fitness of deaf athletes when compared to the control group maximal oxygen consumption (VO2max) (40.3±9.8 mL/kg/min vs. 50.7±4.7 mL/kg/min, P= 0.01), oxygen pulse (15.3±4.8 mL/bpm vs. 20.7±2.6 mL/bpm, P=0.01) and ventilation (70.1±22 L/min vs. 96.2±15 L/min, P=0.01), respectively. The relative torque peak of the dominant knee flexors was significantly lower in the deaf group when compared to the control (1.5±0.2 N.m/kg vs. 1.9±0.2 N.m/kg, P=0.004), respectively. There was a significant correlation between VO2max and peak torque of the dominant knee flexors (r s=0.83, P<0.001) and extensors (r s=0.65, P=0.006). When compared to players with normal hearing, deaf players showed lower cardiorespiratory fitness and decreased knee flexor strength. The performance of the thigh muscles was associated with aerobic capacity.

Comparison of epoc and recovery energy expenditure between hiit and continuous aerobic exercise training / Comparação do epoc e gasto energético de recuperação entre hiit e aeróbicos contínuos / Comparación del epoc y gasto energético de recuperación entre hiit y aeróbicos continuos

ABSTRACT Objectives: The objective of this study was to compare EPOC - excess post-exercise oxygen consumption and recovery energy expenditure between high intensity interval aerobic exercise (HIIT) and continuous aerobic exercise in adult amateur runners. Methods: The study included 10 runners, with a mean age of 35.7 ± 5.87 years, height 1.69 ± 0.11 m; body mass 74.13 ± 11.26 kg; fat percentage 19.31 ± 4.27% and maximal oxygen consumption (VO2max) of 3.50 ± 0.64 l/kg/min-1. The continuous aerobic exercise protocol consisted of 20 minutes of running with intensity of 70-75% HRmax. Two 20-second cycles of 8 sprints were performed for HIIT at the highest possible speed, with 10 seconds of rest and a 3-minute interval between cycles. The sample group performed the two protocols at least 48 hours and at most one week apart. EPOC was observed using ergospirometry after the running protocols, and mean consumption was analyzed between 25-30 minutes after exercise. Oxygen consumption at 9-10 minutes was used for resting consumption. The study has a cross-sectional experimental design. Results: Oxygen consumption of 0.57 ± 0.29l/kg/min1 and energy expenditure of 2.84 ± 1.44 kcal/min were observed for continuous aerobic exercise, with values of 0.61 ± 0.62 l/kg/min−1 and 3.06 ± 1.10 kcal/min respectively (p <0.05) for HIIT. Conclusion: The protocols performed did not show a statistically significant difference in terms of EPOC and energy expenditure, but the performance of HIIT increased lipid metabolism for exercise recovery, which may favor the weight loss process. Moreover, this activity model takes up less time. Level of evidence I, randomized clinical trial.

RESUMO Objetivos: O presente estudo teve como objetivo comparar o EPOC - consumo excessivo de oxigênio pós-exercício - e o gasto energético na recuperação entre o exercício aeróbico intervalado de alta intensidade (HIIT) e os aeróbicos contínuos em corredores amadores adultos. Métodos: Fizeram parte do estudo 10 corredores com idade média de 35,7 ± 5,87 anos, estatura 1,69 ± 0,11 m; massa corporal 74,13 ± 11,26 kg; percentual de gordura 19,31 ± 4,27% e consumo máximo de oxigênio (VO2máx.) de 3,50 ± 0,64 l/kg/min−1. O protocolo de exercício aeróbico contínuo consistiu em 20 minutos de corrida com intensidade de 70-75% FCM. Para HIIT foram realizados dois ciclos de 8 sprints de corrida na maior velocidade possível, com duração de 20 segundos/10 segundos de descanso e três minutos de intervalo entre os ciclos. A amostra realizou os dois protocolos com no mínimo 48 horas e no máximo uma semana de intervalo. Após os protocolos de corrida, observou-se o EPOC através da ergoespirometria e foi analisado o consumo médio entre 25-30 minutos após o exercício. Para o consumo em repouso, utilizou-se o consumo de oxigênio de 9-10 minutos. O estudo possui delineamento experimental do tipo transversal. Resultados: Observaram-se um consumo de oxigênio de 0,57 ± 0,29 l/kg/min−1 e um gasto energético de 2,84 ± 1,44 kcal/min para o exercício aeróbico contínuo, já para o HIIT 0,61 ± 0,62 l/kg/min−1 e 3,06 ± 1,10 kcal/min respectivamente (p<0,05). Conclusão: Os protocolos realizados não demonstraram diferença estatística significativa em relação ao EPOC e ao gasto energético, porém a realização do HIIT aumentou o metabolismo dos lipídeos para a recuperação do exercício, podendo favorecer o processo de emagrecimento, além de ser necessário um menor tempo para praticar esse modelo de atividade. Nível de evidência I, estudo clínico randomizado.

RESUMEN Objetivos: El presente estudio tuvo como objetivo comparar el EPOC - consumo excesivo de oxígeno post ejercicio - y el gasto energético en la recuperación entre el ejercicio aeróbico con intervalos de alta intensidad (HIIT) y los aeróbicos continuos en corredores amateurs adultos. Métodos: Formaron parte del estudio 10 corredores con edad promedio de 35,7 ± 5,87 años, estatura 1,69 ± 0,11 m; masa corporal 74,13 ± 11,26 kg; porcentual de grasa 19,31 ± 4,27% y consumo máximo de oxígeno (VO2máx.) de 3,50 ± 0,64 l/kg/min−1. El protocolo de ejercicio aeróbico continuo consistió en 20 minutos de carrera con intensidad de 70-75% FCM. Para HIIT fueron realizados dos ciclos de 8 sprints de carrera en la mayor velocidad posible, con duración de 20 segundos/10 segundos de descanso y tres minutos de intervalo entre los ciclos. La muestra realizó los dos protocolos con como mínimo 48 horas y como máximo una semana de intervalo. Después de los protocolos de carrera, se observó el EPOC a través de la ergoespirometría y fue analizado el consumo promedio entre 25-30 minutos después del ejercicio. Para el consumo en reposo, se utilizó el consumo de oxígeno de 9-10 minutos. El estudio posee delineación experimental del tipo transversal. Resultados: Se observó un consumo de oxígeno de 0,57 ± 0,29 l/kg/min−1 y un gasto energético de 2,84 ± 1,44 kcal/min para el ejercicio aeróbico continuo, ya para el HIIT 0,61 ± 0,62 l/kg/min−1 y 3,06 ± 1,10 kcal/min respectivamente (p<0,05). Conclusión: Los protocolos realizados no demostraron diferencia estadística significativa con relación al EPOC y al gasto energético, aunque la realización del HIIT aumentó el metabolismo de los lípidos para la recuperación del ejercicio, pudiendo favorecer el proceso de adelgazamiento, además de ser necesario un menor tiempo para practicar ese modelo de actividad. Nivel de evidencia I, estudio clínico aleatorizado.