Background: To investigate the acute effects of a capsaicin analogue supplement on 10 km time-trial performance and physiological responses in amateur athletes. Methods: Twenty-one participants (age = 29.3 ± 5.5 years, weight 74.2 ± 11.3 kg, height 176.0 ± 0.0 cm, fat mass 12.7 ± 3.8%, V˙O2max 62.7 ± 8.4 mL·k−1·min−1), completed two randomized, double-blind trials: capsaicin analogue condition (Capsiate (CAP) = 24 mg) or a placebo (PLA) condition. The participants consumed two doses of 12 mg of CAP or PLA capsule 45 min before and immediately at the start of each trial. The time required to complete 10 km, lactate concentration, maximum heart rate (HRpeak), and rating of perceived exertion (RPE) were recorded. Results: The 10 km time-trial performance (CAP = 45.07 ± 6.41 min vs. PLA = 45.13 ± 6.73, p = 0.828) was not statistically significantly different between conditions. No statistically significant differences between conditions were detected for lactate concentration (p = 0.507), HRpeak (p = 0.897) and RPE (p = 0.517). Conclusion: Two doses of a 12 mg Capsaicin analogue supplement did not improve performance and physiological responses in a 10 km running time-trial in amateur athletes.

RESUMO: O objetivo do estudo foi analisar e comparar os ganhos de força e observar o comportamento da percepção subjetiva de dor (PSD) no período de oito semanas em mulheres sedentárias através de dois programas distintos de exercícios resistidos. O estudo foi composto de 16 mulheres (27,5 ± 4,8 anos; 57 ± 3,9 kg; 162,8 ± 3,3 cm; 21,4 ± 1, kg/m 2 ), aparentemente saudáveis e sedentárias. Elas foram separadas aleatoriamente em dois grupos distintos: Grupo 1 (G1) -os indivíduos nas duas primeiras semanas realizaram duas séries em 10 repetições com carga que variava de 40 a 60% do peso corporal. Entre a 3 a e a 4 a semana treinaram com três séries de 10 repetições a 80% de 1RM (repetição máxima). Entre a 5 a e a 8 a semana ocorreu aumento progressivo do número de séries para quatro, mantendo o número de repetições (10 repetições) e a mesma sobrecarga; Grupo 2 (G2) -foi realizado um programa de treinamento contínuo de três séries de 10 repetições nas duas primeiras semanas com uma carga que variava de 40 a 60% do peso corporal. Nas semanas subseqüentes o treinamento foi alterado para quatro séries de 10 repetições com uma carga equivalente a 80% de 1RM ao longo das oito semanas de treinamento. Para análise da força muscular foi utilizado o teste de 1RM no final da 2 a , 4 a , 6 a e 8 a semanas com intuito de verificar o comportamento da força muscular e otimizar a carga de treinamento. Os exercícios utilizados no protocolo de treinamento e no teste de 1RM foram: leg press 45°, extensão de joelho, flexão de joelho, puxada pela frente, flexão de cotovelo e extensão de cotovelo. A PSD foi apresentada a cada voluntário 48h pós a realização de cada teste de 1RM. A ANOVA Two Way seguida do teste post hoc de Bonferroni verificou que os resultados intra-grupos para G1 apresentaram diferença significativa para todos os exercícios em todos os testes. Contudo, em G2 a diferença significativa foi observada, em grande parte dos exercícios, somente do 3º e 4º teste em relação ao 1º teste. Para as análises inter-grupos o teste Mann-Whitney para amostras independentes verificou ganhos de força significativo do G1 em relação a G2 nos exercícios leg press 45°, rosca tríceps e rosca bíceps. Em relação a PSD foi observada uma queda significativa na escala analógica de G1 em relação a G2 (p<0,001). Em conclusão, a sobrecarga progressiva imposta ao G1 promoveu significativos ganhos de força muscular e menor PSD em relação ao G2.Descritores: Força Muscular. Exercício Físico. Dor Muscular Tardia.

Introduction: There is a high incidence of Anterior Cruciate Ligament (ACL) injuries in soccer and 37% of this happens during landing after a jumping event. The measure of valgus knee moment during landing of a Drop Jump (DJ) has been considered a gold standard test to predict the risk of ACL injury in young athletes. Furthermore, researchers have used 2D frontal angle of the knee trying to make a practical tool to evaluate this injury risk, however, to the best of our knowledge, there is no studies about the relationship between mechanical load and 2D dynamic knee valgus parameters. Purpose: To verify the relationship between kinetics and kinematics ACL injury risk factors: the GRF and the a) peak knee valgus; b) valgus knee displacement in soccer players wearing soccer boots landing on an official synthetic turf. Methods: Twenty Brazilian soccer players, 15-17 years old, with 176.6 ± 6.4 cm of height and 67.4 ± 8.1 kg of body mass participated in this study. Following familiarization, subjects performed the DJ from a height of 40 cm. They landed on two force plates synchronized with Vicon system for kinetic and kinematic analyses, respectively. Results: Only valgus knee displacement (-1.4 ± 7.0 °) and antero-posterior component of GRF (-0.402 ± 0.097 BW) presented a significant relationship (r = 0.353; p = 0.025). Conclusion: There is a significant correlation between knee valgus displacement and GRF antero-posterior component for soccer players in an official artificial turf using soccer boots.

Background: To investigate the acute effects of a capsaicin analogue supplement on 10-km time trial performance and physiological responses in amateur athletes. Methods: Twenty-one participants (age = 29.3 ± 5.5 years), completed two randomized, double-blind trials: capsaicin analogue condition [Capsiate (CAP) = 24 mg] or a placebo condition. The participants consumed two doses of 12 mg of capsaicin or placebo capsule 45 minutes before and immediately at the start of each trial. The time required to complete 10-km, lactate concentration, maximum heart rate (HRpeak), and rating of perceived exertion (RPE) were recorded. Results: 10-km time-trial performance (CAP = 45.07 ± 6.41 min vs. placebo = 45.13 ± 6.73, P = 0.828) was not statistically significant different between conditions. No statistically significant differences between conditions were detected for lactate concentration (P = 0.507), HRpeak (P = 0.897) and RPE (P = 0.517). Conclusion: Two doses of 12 mg Capsaicin analogue supplementation did not improve performance and physiological responses in a 10-km running time-trial in amateur athletes.

Background: To investigate the acute effect of capsaicin analog supplementation on 10-km time-trial running performance and physiological responses in amateur athletes. Methods: Twenty-one participants (age = 29.3 ± 5.5 years), completed two randomized, double-blind trials: capsaicin analog condition [Capsiate (CAP) = 24 mg] or a placebo condition. The participants consumed two doses of 12 mg of capsaicin or placebo capsule 45 minutes before and immediately at the start of each trial. The time required to complete 10-km in minutes, lactate concentration, maximum heart rate (HR), and rating of perceived exertion (RPE) were recorded. Results: 10-km time-trial performance (CAP= 44.4 ± 6.3 min vs placebo= 45.3 ± 6.8 min, P = 0.823) was not statistically significant different between conditions. No statistically significant differences between conditions were detected for lactate concentration (P = 0.507), HR (P = 0.897) and RPE (P = 0.517). Conclusion: Capsaicin analog supplementation did not improve performance and physiological responses in a 10-km running time-trial in amateur athletes.