Effects of different voluntary forces of dynamic stretching on maximal dorsiflexion angle of the ankle joint and subjective fatigue / 体力科学

This study aimed to examine the effects of different voluntary forces of dynamic stretching (DS) on the maximal dorsiflexion angle of the ankle joint, passive torque, and subjective fatigue. Eleven healthy male participants were included in this study. Ankle angle and passive torque were measured before and after DS, which involved four sets of ankle plantarflexion-dorsiflexion performed for 30 s while sitting on an isokinetic machine with the knees fully extended. Although ankle plantarflexion was passively performed via an isokinetic machine, participants were instructed to perform the active ankle dorsiflexion under either of the following two conditions: with maximal voluntary contraction (MVC) (DSmax) or with submaximal voluntary contraction (DSsub). In DSsub, 80% MVC was set as the target voluntary force. Subjective fatigue during DS was measured using the visual analogue scale. In DSsub, participants actually demonstrated 87.0 ± 5.8% MVC. The maximal ankle dorsiflexion angle significantly increased after DS in both conditions. Subjective fatigue was significantly greater after two, three, and four sets of DSmax than after the corresponding repetitions of DSsub. Although passive torque at the maximal dorsiflexion angle tended to increase after stretching, no significant changes were observed in the passive torque from before to after DS. These results compared MVC with approximately 87% MVC, indicating that the voluntary force of DS did not influence the increment of the maximal dorsiflexion angle after DS. Our study findings also suggested that 80–90% MVC is recommended during DS to increase the maximal dorsiflexion angle without excessive subjective fatigue.

Comparação entre o efeito imediato e agudo de três protocolos de alongamento dos músculos isquiotibiais e paravertebrais / Comparison between the immediate and acute effect of three stretching protocols of hamstrings and paravertebral muscles

JUSTIFICATIVA E OBJETIVOS: Vários estudos apontam que o alongamento muscular aumenta a flexibilidade, mas poucas pesquisas comparam métodos no seu efeito imediato e agudo, principalmente com respeito ao chamado cinesioalongamento. O objetivo deste estudo foi comparar o efeito imediato e agudo de três protocolos de alongamento dos músculos isquiotibiais e paravertebrais, quanto à flexibilidade articular e a extensibilidade muscular. MÉTODO: Utilizou-se 41 voluntários, com extensibilidade de isquiotibiais limitada. Os participantes foram aleatorizados em três grupos: alongamento ativo estático (AE) (n = 14), facilitação neuromuscular proprioceptiva (FNP) (n = 14) e cinesioalongamento (CA) (n = 13). Realizaram-se três avaliações por prancha de goniometria e pelo banco de Wells; a primeira antes do protocolo de alongamento, a segunda imediatamente após e a terceira 24 horas após. Os alongamentos foram realizados em ambos os membros inferiores e sustentados por 32 segundos. Os dados foram analisados pela Análise de Variância, com nível de significância 5%. RESULTADOS: houve diferença significativa entre a primeirae a segunda avaliação para grupos AE e CA na prancha de goniometria. Todos os grupos apresentaram diferença significativa entre a segunda e terceira avaliação. Quando observados os resultados obtidos com a avaliação do banco de Wells, houve diferenças ignificativa em todos os grupos se comparado a primeira avaliação com a segunda. Quando se comparou a segunda e terceira avaliação, os grupos AE e FNP apresentaram diferença significativa. Não houve diferença significativa quando comparado os três protocolos de alongamento entre si, nos dois instrumentos. CONCLUSÃO: O efeito imediato do alongamento é o aumento da flexibilidade articular e da extensibilidade muscular. Já o efeito agudo mostrou que há uma perda dos ganhos obtidos, não sendos ignificativa no grupo CA.

BACKGROUND AND OBJECTIVES: Several studies show that muscle stretching increases flexibility, but little research comparing methods in your immediate and acute, especially with respect to the call kinesiostretching. To evaluate and compare acute and immediate effects of three protocols for stretching hamstrings and paravertebral muscles, as the joint flexibility and muscle extensibility. METHOD: We used 41 volunteers, with hamstrings limited extensibility.The participants were randomized into three groups:active static stretching - AS (n = 14), proprioceptive neuromuscularfacilitation - PNF (n = 14) and kinesiostretching - KS (n= 13). In total, three assessments by goniometry board and Wells bench, the first before the stretching protocol, immediately after the second and third after 24 hours. The stretches were performed in both legs and sustained for 32 seconds. The data were analyzed by ANOVA with significance level of 5%. RESULTS: The goniometry evaluation board there was significant difference between the first and second assessment for groups AE and KS. All groups showed significant difference between the second and third assessment. When observing results of the evaluation of the Wells bench was significant in all groups when compared to the first evaluation with the second. When comparingthe second and third assessment, the groups AE and PNF showed significant difference. There was no significant difference when comparing each stretching protocols among them selves. CONCLUSION: The immediate effect of stretching is to increase joint flexibility and extensibility of muscle. Since the acute effect showed that there are a loss of gain obtained, not beingsignificant in the KS.