Exercícios de alongamento e respostas cardiovasculares

Abstract

This dissertation was composed of three studies, aimed to (1) verify the acute effect of stretching exercises on the blood pressure of healthy subjects and discuss the possible physiologics mechanisms underlying these responses; (2) the effect of muscle stretching on heart rate variability (HRV), as well as discussing the possible mechanisms involved in these responses; (3) to verify the effect of the level of flexibility and the volume of stretching exercises on the HRV. In the first study, 254 and 86 healthy participants who performed proprioceptive neuromuscular (PNF) and static stretching stretches, respectively. In the second study a systematic review of 231 studies was carried out, of which 4 studies were selected. In the third study, an experiment was performed comparing four groups: low flexibility and low elongation volume (n = 12), low flexibility and high elongation volume (n = 13), great flexibility and low elongation volume A lot of flexibility and a high volume of stretching (n = 13). The results obtained in the meta-analysis showed that the performance of the PNF stretches increased systolic blood pressure (SBP) and diastolic blood pressure (DBP) with differences in mean and confidence interval differences of 12.26 (9.48-15.04) and 6.67 (-1.90-15.23) and P <0.00001 and P <0.00001 respectively and static elongation was not able to produce significant increases in SBP and DBP, with differences in mean and confidence interval of 7.62 (5.74-9.50) and 0.62 (-0.52-1.77) and P = 0.13 and P = 0.28 respectively. In the systematic review the existing results on stretching exercises and HRV are few and contradictory, pointing to a hypothesis of the level of flexibility and volume of stretching exercises that may cause differences in HRV. In the experimental study, the results showed that regardless of the level of flexibility, performing a session of muscle stretching with low or high volume is already capable of producing significant effects on HRV. Therefore, it was concluded that the execution of PNF stretches causes a significant increase of SBP and DBP and static stretching does not generate significant increases in SBP and DBP, which despite the few contradictory studies based on the review studies, seems that the level of flexibility of the individuals and the volume of the stimulus can directly influence the HRV and after the experimental study, that the passive static stretching exercises are able to modify the HRV significantly. Given that, the level of flexibility and the volume of exercises are not able to influence these responses