Effect of photobiomodulation on maximal lactate production rate on swimmers: a randomized, crossover, double-blind and placebo-controlled study

Abstract Aim: This study aimed to verify the acute effect of photobiomodulation (PBM) on maximal lactate production rate (VLamax) in front crawl swimmers. Methods: Fifteen male swimmers (20.9 ± 2.4-year-old) participated in this study. Three sets of front crawls were performed at distances of 100-, 200- and 400-m under three experimental conditions: PBM (420 J), placebo (PLA) and control (C) in this randomized, crossover, double-blind and placebo-controlled study. PBM or PLA were applied or simulated before performance tests. One-way Anova for repeated measurements were used for statistical analyses. Results: The results showed that the prior PBM application did not affect VLamax in front crawl swimmers: VLamax 100-m (PBM = 0.20 ± 0.05 mmol·L-1·s-1; PLA = 0.20 ± 0.04 mmol·L-1·s-1 and C = 0.21 ± 0.04; mmol·L-1·s-1); 200-m (PBM = 0.09 ± 0.03 mmol·L-1·s-1; PLA = 0.08 ± 0.02 mmol·L-1·s-1 and C = 0.08 ± 0.02 mmol·L-1·s-1) and 400-m (PBM = 0.04 ± 0.01 mmol·L-1·s-1; PLA = 0.04 ± 0.01 mmol·L-1·s-1 and C = 0.03 ± 0.01 mmol·L-1·s-1). Nor effect swim time (ST) performance: ST 100 m (PBM = 65.5 ± 6.3 s; PLA = 65.2 ± 5.6 s; C = 66.0 ± 5.9 s); ST 200 m (PBM = 148.5 ± 17.9 s; PLA = 149.4 ± 16.4 s; C = 150.1 ± 17.9 s); ST 400 m (PBM = 327.7 ± 38.2 s; PLA = 321.6 ± 47.7 s; C = 329.5 ± 41.2 s). Conclusions: PBM application prior front crawl swimming tests did not significantly modify the VLamax on swimmers covering distances of 100-, 200- and 400-m.

Autoeficácia e nível de ansiedade em atletas jovens do atletismo paranaense / Self-efficacy and level of anxiety in young track and athletes from Paraná

Este estudo analisou a autoeficácia em relação ao nível de ansiedade de atletas do atletismo no Estado do Paraná. A amostra constituiu-se de 75 atletas de idade média de 16,76 anos e de ambos os sexos. Como instrumento foram utilizados o Inventário de Ansiedade Estado Competitiva (CSAI-2), e um questionário estruturado para identificar a autoeficácia. Para análise estatística, foram utilizados os testes Kolmogorov-Smirnov, Mann--Whitney e Kruskall-Wallis. Os resultados indicaram que não houve diferença significativa nos níveis de ansiedade quanto ao gênero; para as mulheres, não foram encontradas diferenças significativas entre expectativa de resultado e níveis de ansiedade; os homens que obtiveramresultado superior ao esperado apresentaram maior nível de ansiedade. Concluiu-se que os atletas com altas expectativas de resultado apresentaram níveis maiores de ansiedade cognitiva e somática e de autoconfiança.

This study analyzed self-efficacy in relation to anxiety level in young track and athletes from Paraná state. The sample consisted of 75 athletes of both genders with a mean age of 16.76 years. The Competitive State Anxiety Inventory (CSAI-2) was used to assess competitive state anxiety and a structured questionnaire was used to identify self efficacy. The Kolmogorov--Smirnov, Mann-Whitney, and Kruskal-Wallis tests were used for statistical analysis. The results showed no significant difference in anxiety levels between genders. For women, no significant differences were observed between outcome expectancy and anxiety level. Men who achieved a better result than expected presented a higher anxiety level. In conclusion, athletes with high outcome expectations show higher levels of cognitive and somatic anxiety and self-confidence.

Crianças e desempenho motor: um estudo associativo / Children and motor performance: the associate study

O estudo de caráter descritivo objetivou investigar a associação entre o desempenho motor, percepção de competência e índice de massa corporal de crianças de 8 a 10 anos. Foram sujeitos do estudo 75 crianças da rede de ensino publico. Os instrumentos utilizados foram: Test of Gross Motor Development 2 (TGMD-2), Ulrich (2000), Self Perception Profile de Harter (1985) e Índice de massa corporal (IMC). A Coleta de dados ocorreu individualmente. Para análise dos dados foi utilizado o Teste Kolmogorov–Smirnov e o teste Exato de Fisher para P≤ 0,05. Os resultados demonstraram que 97,22% das crianças apresentaram percepção de competência moderada e alta, 97,22% desempenho motor muito pobre/pobre e 83,34% IMC normal. Conclui-se assim, que não houve a associação entre as variáveis de desempenho motor, percepção de competência e IMC, os quais indicam uma tendência das crianças desta faixa etária a superestimarem suas competências não sendo precisas em suas percepções.

This descriptive study had as objective to investigate the association between motor performance, perceived competence and body mass index of 8 to 10 year old children. Participated on this study 75 children enrolled in the public network teaching. The instruments were: Test of Gross Motor Development 2 (TGMD-2), Ulrich (2000), Self Perception Profile by Harter (1985) and the Body mass index (BMI). Data were collected individually. Data analysis was performed by the Kolgoromov-Smirnov test and Fisher’s exact test with a significance of P≤ 0,05. The results showed that 97,22% of the children demonstrated high and moderate perceived competence, 97,22% of the children showed poor/very poor motor development and 83,33% showed normal BMI. It is concluded, therefore, that there was no association between motor performance variables, perceived competence and BMI, indicating that children in this age line tend to overestimate their competences, being inaccurate in their perceptions.