Can Adipose Tissue Influence the Evaluation of Thermographic Images in Adolescents?

Infrared thermography (IRT) is a technology easy to use for clinical purposes as a pre-diagnostic tool for many health conditions. However, the analysis process of a thermographic image needs to be meticulous to make an appropriate decision. The adipose tissue is considered a potential influence factor in the skin temperature (Tsk) values obtained by IRT. This study aimed to verify the influence of body fat percentage (%BF) on Tsk measured by IRT in male adolescents. A total of 100 adolescents (16.79 ± 0.97 years old and body mass index of 18.41 ± 2.32 kg/m²) was divided into two groups through the results of a dual-energy X-ray absorptiometry analysis: obese (n = 50, %BF 30.21 ± 3.79) and non-obese (n = 50, %BF 11.33 ± 3.08). Thermograms were obtained by a FLIR T420 infrared camera and analyzed by ThermoHuman® software version 2.12, subdividing the body into seven regions of interest (ROI). The results showed that obese adolescents presented lower mean Tsk values than the non-obese for all ROIs (p < 0.05), with emphasis on the global Tsk (0.91 °C) and anterior (1.28 °C) and posterior trunk (1.18 °C), with "very large" effect size values. A negative correlation was observed in all the ROI (p < 0.01), mainly in the anterior (r = -0.71, p < 0.001) and posterior trunk (r = -0.65, p < 0.001). Tables of thermal normality were proposed for different ROIs according to the classification of obesity. In conclusion, the %BF affects the registered Tsk values in male Brazilian adolescents assessed by IRT.

Creatine improves anaerobic performance and promotes anthropometric changes in Brazilian college soccer players / La creatina mejora el rendimiento anaeróbico y promueve cambios antropométricos en futbolistas universitarios brasileños

Objective: This study aimed to evaluate the effects of creatine on the body composition and performance of college soccer players. Materials and method: Sixteen amateur soccer players were supplemented with creatine (n=8) or maltodextrin (placebo, n=8) for four weeks, using a loading protocol (20g/day in the first week, followed by 5g/day for the rest of the study period). Anthropometric measurements and three physical tests were performed before and after the intervention. Results: After the protocol, the Cr group showed increased body mass (pre 65.1 ± 8.2; post 66.4 ± 8.4; p=0.002), arm (pre 27.7 ± 4.3; post 28.3 ± 4.3; p=0.01), thigh (pre 49.9 ± 4.3; post 51.3 ± 4.6; p=0.012), and leg (pre 34.6 ± 2.3; post 34.8 ± 2.4; p=0.029) circumferences. For bangsbo repeat vertical jump test (BRVJ), there was an increase in maximum power (pre 2965.4 ± 691.8; post 3102.1 ± 818; p=0.034), maximum relative power (pre 44.5 ± 6.5; post 47.1 ± 6.5; p=0.045) and average power (pre 2757.6 ± 653.2; post 2937.7 ± 739.9; p=0.05) only in the Cr group. For running anaerobic sprint test (RAST), there was a significant improvement in average sprint and total times, and in the average power for both groups; however, only the Cr group showed significant improvement in maximum power (pre 517.93 ± 118.82; post 580.15 ± 119.06; p=0.01) and maximum relative power (pre 7.9 ± 1.2; post 8.5 ± 1.3; p<0.001). For wingate test (WIN), improvements were observed in maximum power (pre 456.4 ± 91.0; post 508 ± 79.7; p=0.003), maximum relative power (pre 7.0 ± 0.9; post 7.6 ± 0.6; p=0.012), average power (pre 354.8 ± 69.5; post 410 ± 71.5; p<0.001) and relative average power (pre 5.4 ± 0.6; post 6.1 ± 0.4; p=0.012) only in the Cr group.(AU)

Objetivo: Evaluar los efectos de la creatina en la composición corporal y el rendimiento anaeróbico en jugadores de fútbol universitario. Material y método: Dieciséis jugadores fueron suplementados con creatina (Cr) (n=8) o maltodextrina (placebo, n=8) durante cuatro semanas, utilizando un protocolo de carga (20g/día la primera semana, seguidos de 5g/día durante el resto del período de estudio), realizándose mediciones antropométricas y tres pruebas físicas anaeróbicas antes y después de la intervención. Resultados: El grupo Cr mostró un aumento en las circunferencias del brazo (antes 27,7 ± 4,3; después 28,3 ± 4,3; p=0,01), muslo (antes 49,9 ± 4,3; después 51,3 ± 4,6; p=0,012) y pierna (antes 34,6 ± 2,3; después 34,8 ± 2,4; p=0,029) y aumento en la masa corporal (antes 65,1 ± 8,2; después 66,4 ± 8,4; p=0,002). No se registraron cambios significativos en el grupo placebo. En la prueba de saltos verticales repetidos (Test de Bangsbo) hubo un aumento en la potencia máxima (antes 2965,4 ± 691,8; después 3102,1 ± 818; p=0,034), relativa máxima (antes 44,5 ± 6,5; después 47,1 ± 6,5; p=0,045) y media (antes 2757,6 ± 653,2; después 2937,7 ± 739,9; p=0.05) solo en el grupo Cr. En la prueba de carrera (RAST), hubo una mejora significativa en los tiempos de sprint total y promedio, y en la potencia promedio para ambos grupos; sin embargo, únicamente el grupo Cr mostró una mejora significativa en la potencia máxima (antes 517,93 ± 118,82; después 580,15 ± 119,06; p=0,01) y máxima relativa (antes 7,9 ± 1,2; después 8,5 ± 1,3; p<0,001). Para la prueba de Wingate en miembros superiores, se observaron mejoras en potencia máxima (antes 456,4 ± 91,0; después 508 ± 79,7; p=0,003), relativa máxima (antes 7,0 ± 0,9; después 7,6 ± 0,6; p=0,012), media (antes 354,8 ± 69,5; después 410 ± 71,5; p<0,001) y potencia relativa media (antes 5,4 ± 0,6; después 6,1 ± 0,4; p=0,012) solo en el grupo Cr.(AU)

Impact of airflow on body cooling in exercise: an exploratory study / Impacto del flujo de aire en el enfriamiento del cuerpo en el ejercicio: un estudio exploratorio

Objective: To analyze the body heat dissipation by thermography during indoor running treadmill with different airflowconditions.Materials and method: Nine male participants (23.0±2.5 years old) underwent three 45-minute moderate-intensity runningsessions (60-70% reserve heart rate) on a treadmill. At each session, a different experimental condition was applied in a cros-sover design: without airflow (NF), and with low (LF) and high airflow (HF) generated by a fun. Thermograms were obtainedwith a thermal camera before exercise, during (every 10 minutes), and after exercise. Skin temperature (Tsk) was measuredon regions of interest of the upper body: pectoral, brachial biceps, and upper back. A repeated measures ANOVA was usedto compare Tsk over time and between conditions, considering p<0.05 as statistically significant.Results: In pectoral and brachial biceps, LF and HF conditions provided greater reductions in Tsk at all moments when com-pared to the NF (p<0.05). There was a higher reduction in Tsk to the HF vs LF in biceps at 30, 40, and 45 min during exercise(p<0.05). In the upper back, Tsk remained below baseline at all moments during exercise only in the HF condition (p<0.05).In NF and LF conditions, Tsk returned to baseline at 30 min during exercise (p>0.05).Conclusion: The frontal wind flow enhances body heat dissipation during moderate-intensity running in the pectoral, brachialbiceps, and upper back, with a direct relationship of flow speed and Tsk reduction during exercise.(AU)

Objetivo: Analizar el disipación del calor corporal mediante termografía en ejercicio de carrera en tapiz con diferentescondiciones de flujo de aire.Material y método: Nueve hombres (23,0±2,5 años) se sometieron a tres sesiones de 45 minutos de carrera de intensidadmoderada (60-70% frecuencia cardíaca de reserva) en tapiz, bajo tres condiciones diferentes en un diseño cruzado: sin flujo deaire (NF) y con flujo de aire bajo (LF) y alto (HF) generado por un ventilador. Los termogramas se obtuvieron con una cámaratérmica antes del ejercicio, durante y después del ejercicio, midiéndose la temperatura de la piel (Tp) en las regiones de interésdel pectorales, bíceps braquiales y parte superior de la espalda. Se utilizó un ANOVA de medidas repetidas para comparar Tpen función del tiempo y entre condiciones, considerando p<0,05 como estadísticamente significativo.Resultados: En los pectorales y bíceps braquiales, las condiciones LF y HF redujeron en todo momento la Tp comparadas conNF (p<0,05). La reducción de Tp fue mayor con HF que con LF en bíceps a los 30, 40 y 45 min (p<0,05). En la espalda superior,la Tp se mantuvo siempre por debajo de la línea base durante el ejercicio solo en la condición HF (p<0,05). En condicionesde NF y LF la Tp volvió a valores de referencia a los 30 min de ejercicio (p>0,05).Conclusiones: El flujo de viento frontal mejora la disipación del calor corporal en pectorales, bíceps braquiales y parte superiorde la espalda durante la carrera de intensidad moderada, con una relación directa de la velocidad del flujo y la reducción dela Tp durante el ejercicio.(AU)

Global Active Stretching (SGA®) Practice for Judo Practitioners' Physical Performance Enhancement.

In order to analyze the Global Active Stretching (SGA®) practice on the physical performance enhancement in judo-practitioner competitors, 12 male athletes from Judo Federation of Sergipe (Federação Sergipana de Judô), were divided into two groups: Experimental Group (EG) and Control Group (CG). For 10 weeks, the EG practiced SGA® self-postures and the CG practiced assorted calisthenic exercises. All of them were submitted to a variety of tests (before and after): handgrip strength, flexibility, upper limbs' muscle power, isometric pull-up force, lower limbs' muscle power (squat-jump - SJ and countermovement jump - CMJ) and Tokui Waza test. Due to the small number of people in the sample, the data were considered non-parametric and then we applied the Wilcoxon test using the software R version 3.3.2 (R Development Core Team, Austria). The effect size was calculated and considered statistically significant the values p ≤ 0.05. Concerning the results, the EG statistical differences were highlighted in flexibility, upper limbs' muscle power and lower limbs' muscle power (CMJ), with a gain of 3.00 ± (1.09) cm, 0,42 ± (0,51) m and 2.49 ± (0.63) cm, respectively. The CG only presented statistical difference in the lower limbs' test (CMJ), with a gain of 0,55 ± 2,28 cm. Thus, the main results pointed out statistical differences before and after in the EG in the flexibility, upper limbs and lower limbs' muscle power (CMJ), with a gain of 3.00 ± 1.09 cm, 0.42 ± 0.51 m 2.49 ± 0.63 cm, respectively. On the other hand, the CG presented a statistical difference only the lower limbs' CMJ test, with a gain of 0.55 ± 2.28 cm. The regular 10-week practice of SGA® self-postures increased judoka practitioners' posterior chain flexibility and vertical jumping (CMJ) performance.