Complex Network Model Reveals the Impact of Inspiratory Muscle Pre-Activation on Interactions among Physiological Responses and Muscle Oxygenation during Running and Passive Recovery.

Although several studies have focused on the adaptations provided by inspiratory muscle (IM) training on physical demands, the warm-up or pre-activation (PA) of these muscles alone appears to generate positive effects on physiological responses and performance. This study aimed to understand the effects of inspiratory muscle pre-activation (IMPA) on high-intensity running and passive recovery, as applied to active subjects. In an original and innovative investigation of the impacts of IMPA on high-intensity running, we proposed the identification of the interactions among physical characteristics, physiological responses and muscle oxygenation in more and less active muscle to a running exercise using a complex network model. For this, fifteen male subjects were submitted to all-out 30 s tethered running efforts preceded or not preceded by IMPA, composed of 2 × 15 repetitions (1 min interval between them) at 40% of the maximum individual inspiratory pressure using a respiratory exercise device. During running and recovery, we monitored the physiological responses (heart rate, blood lactate, oxygen saturation) and muscle oxygenation (in vastus lateralis and biceps brachii) by wearable near-infrared spectroscopy (NIRS). Thus, we investigated four scenarios: two in the tethered running exercise (with or without IMPA) and two built into the recovery process (after the all-out 30 s), under the same conditions. Undirected weighted graphs were constructed, and four centrality metrics were analyzed (Degree, Betweenness, Eigenvector, and Pagerank). The IMPA (40% of the maximum inspiratory pressure) was effective in increasing the peak and mean relative running power, and the analysis of the complex networks advanced the interpretation of the effects of physiological adjustments related to the IMPA on exercise and recovery. Centrality metrics highlighted the nodes related to muscle oxygenation responses (in more and less active muscles) as significant to all scenarios, and systemic physiological responses mediated this impact, especially after IMPA application. Our results suggest that this respiratory strategy enhances exercise, recovery and the multidimensional approach to understanding the effects of physiological adjustments on these conditions.

Acute Effects of Foam Rolling on Cycling Performance: A Randomized Cross-Over Study.

Acute foam rolling protocols may increase range of motion without a negative impact on muscle performance. The main purpose of the present study was to investigate the acute effects of foam rolling on cycling performance (mean power and maximal power), affect and perceived exertion. A secondary aim was to assess the effect of foam rolling on post-exercise muscle soreness. In a random order, ten recreationally trained cyclists (age: 26 ± 5 years; height 1.76 ± 0.06 m; total body mass 78.3 ± 19.8 kg; cycling experience: 5.6 ± 5.3 years; 4.1 ± 1.3 cycling sessions per week and 1.4 ± 1.4 strength sessions per week) were submitted to the following experimental conditions (separated by one week) before performing a three-minute, all-out cycling test: foam rolling or control. During foam rolling protocol, participants were instructed to roll back and forth on one leg and to place the opposite leg crossed over, from the proximal to the distal portion of the rectus femoris and vastus lateralis during one set of sixty seconds for each muscle group. Feeling scale (10 min pre and post-test), CR-10 scale of perceived exertion (ten-minute post-test), pressure pain threshold (pre and 24 h post-test) and mean/maximal power were assessed. No significant differences were observed between conditions for mean and maximal power, affect, perceived exertion, and pressure pain threshold (all p > 0.05). In conclusion, a pre-exercise acute session of self-myofascial release does not improve performance and post-exercise muscle soreness of recreationally trained cyclists.

Acute effect of speed test on the skin temperature of elite soccer players / Efeito agudo do teste de velocidade sobre a temperatura da pele de jogadoras de futebol de elite / Efecto agudo del test de velocidad sobre la temperatura de la piel de jugadoras de fútbol de élite

ABSTRACT Introduction Infrared thermography has been used in several areas, mainly in sports training, and specifically in soccer. Objectives The objectives of the study were to verify the acute effect of a displacement speed test on the skin temperature of elite female soccer players, to observe pre- and post-test thermal asymmetries, and to compare responses in the anterior and posterior regions of lower limbs. Methods Cross-sectional study that evaluated 17 soccer players of the 2018 Brazilian Championship. They were submitted to thermography before and 10 minutes after performing the displacement speed test. Thermographic images were collected using a FLIR® model 8 thermal imager and changes in skin temperature in the anterior and posterior regions of the lower limbs were analyzed, according to the areas of interest. Descriptive statistics were performed and mean and standard deviation of the temperatures of the areas of interest were analyzed. The normality of the data was verified, and then the Student's t test for normal paired and independent samples and the Mann-Whitney test for non-normal samples were conducted, with p <0.05 being adopted for significance level. Results It was possible to observe that after the test there was an increase in skin temperature in all the regions analyzed, both on the dominant and non-dominant sides (p <0.05). Regarding the analysis of the anterior region, it was possible to observe a higher temperature (p <0.05) in the region of the tibial muscles than in the region of the quadriceps muscles. Conclusion It is concluded that thermography helps to understand the thermal responses of lower limbs after applying the displacement speed test. The study shows that thermographic evaluation can guide the organization of the training session when motor tests have previously been applied, and in the detection of abnormal overloads, helping to prevent injuries. Level of evidence IV; Therapeutic studies - Investigation of treatment results.

RESUMO Introdução A termografia infravermelha tem sido empregada em diversas áreas, principalmente no treinamento esportivo e especificamente no futebol. Objetivos Os objetivos do estudo foram verificar o efeito agudo da aplicação de um teste de velocidade de deslocamento sobre a temperatura da pele de atletas de futebol feminino de elite, as assimetrias térmicas pré e pós-teste e comparar respostas nas regiões anterior e posterior de membros inferiores. Métodos Estudo de caráter transversal, que avaliou 17 jogadoras de futebol do Campeonato Brasileiro em 2018. Elas foram submetidas à termografia antes e 10 minutos depois da realização do teste de velocidade de deslocamento. Foram coletadas imagens termográficas por meio de um termovisor FLIR®, modelo E8, e analisadas as alterações da temperatura da pele, na região anterior e posterior dos membros inferiores, de acordo com as áreas de interesse. Foi realizada a estatística descritiva e para análise, foram usados média e desvio padrão da temperatura das áreas pretendidas. Verificou-se normalidade dos dados e, em seguida, o teste t de Student para amostras normais pareadas e independentes e o teste de Mann-Whitney, para amostras não normais, adotando-se p < 0,05 para nível de significância. Resultados Foi possível observar que depois do teste houve aumento da temperatura da pele em todas as regiões analisadas, tanto no lado dominante quanto no não dominante (p < 0,05). Com relação à análise da região anterior, foi possível observar maior temperatura (p < 0,05) na região dos músculos tibiais quando comparados com os músculos da região do quadríceps. Conclusão Conclui-se que a termografia auxilia o entendimento das respostas térmicas de membros inferiores depois da aplicação do teste de velocidade de deslocamento. O estudo demonstra que a avaliação termográfica pode orientar a organização da sessão de treinamento quando há aplicação prévia de testes motores e na detecção de sobrecargas anormais, auxiliando na prevenção de lesões. Nível de evidência IV; Estudos terapêuticos - Investigação dos resultados do tratamento.

RESUMEN Introducción La termografía infrarroja ha sido empleada en diversas áreas, principalmente en el entrenamiento deportivo y específicamente en el fútbol. Objetivos Los objetivos del estudio fueron verificar el efecto agudo de la aplicación de un test de velocidad de desplazamiento sobre la temperatura de la piel de atletas de fútbol femenino de élite, las asimetrías térmicas pre y post test y comparar respuestas en las regiones anterior y posterior de miembros inferiores. Métodos Estudio de carácter transversal, que evaluó a 17 jugadoras de fútbol del Campeonato Brasileño en 2018. Ellas fueron sometidas a termografía antes y 10 minutos después de la realización del test de velocidad de desplazamiento. Fueron colectadas imágenes termográficas por medio de un termovisor FLIR® - E8, modelo E8, y analizadas las alteraciones de la temperatura de la piel, en la región anterior y posterior de los miembros inferiores, de acuerdo con las áreas de interés. Fue realizada la estadística descriptiva y para el análisis, fueron usados promedio y desviación estándar de la temperatura de las áreas pretendidas. Se verificó normalidad de los datos y, a continuación, el test t de Student para muestras normales pareadas e independientes, y el test de Mann-Whitney, para muestras no normales, adoptándose p < 0,05 para nivel de significancia. Resultados Fue posible observar que después del test hubo aumento de la temperatura de la piel en todas las regiones analizadas, tanto en el lado dominante como en el no dominante (p <0,05). Con relación al análisis de la región anterior, fue posible observar mayor temperatura (p <0,05) en la región de los músculos tibiales cuando comparados con los músculos de la región del cuádriceps. Conclusión Se concluye que la termografía ayuda en el entendimiento de las respuestas térmicas de miembros inferiores, después de la aplicación del test de velocidad de desplazamiento. El estudio demuestra que la evaluación termográfica puede orientar la organización de la sesión de entrenamiento cuando hay aplicación previa de tests motores y en la detección de sobrecargas anormales, ayudando en la prevención de lesiones. Nivel de evidencia IV; Estudios terapéuticos - Investigación de los resultados del tratamiento.