The acute improvement of performance after photobiomodulation therapy (PBMT) has been reported in different types of exercise. However, the effect on high-intensity and intermittent exercises that are relevant for team sports is unknown. Thus, we evaluated the effect of prior acute application of PBMT on high-intensity and intermittent exercise performance, muscle oxygenation, and physiological/perceptual indicators in amateur female futsal players. Thirteen players (24.1 ± 3.7 years) performed a testing battery (countermovement jump (CMJ), Illinois agility and YoYo intermittent recovery test level 1 (YYIR1)) preceded by 15 min of PBMT (1 min 30 s each muscular point; five muscular points in each lower limbs) or 15 min of placebo (SHAM), in a counterbalanced randomized cross-over design (one-week in-between PBMT/SHAM). All test performance did not differ (p > 0.05) between PBMT and SHAM, as well as blood lactate, rating of perceived exertion, heart rate, and muscle oxygenation (via near infrared spectroscopy) responses. The acute application of PBMT prior to a physical testing battery does not influence high-intensity and intermittent exercises performance, neither physiological nor perceptual responses in amateur female futsal players.

Background: Alterations in the structure of resistance vessels contribute to elevated systemic vascular resistance in hypertension and are linked to sympathetic hyperactivity and related lesions in target organs. Objective: To assess the effects of exercise training on hemodynamic and autonomic parameters, as well as splenic arteriolar damages in male Wistar Kyoto (WKY) and Spontaneously Hypertensive Rats (SHR). Methods: Normotensive sedentary (WKYS) and trained (WKYT) rats, and hypertensive sedentary (SHRS) and trained (SHRT) rats were included in this study. After 9 weeks of experimental protocol (swimming training or sedentary control), arterial pressure (AP) and heart rate (HR) were recorded in freely moving rats. We assessed the autonomic control of the heart by sympathetic and vagal autonomic blockade. Morphometric analyses of arterioles were performed in spleen tissues. The statistical significance level was set at p < 0.05. Results: Resting bradycardia was observed in both trained groups (WKYT: 328.0 +/- 7.3 bpm; SHRT: 337.0 +/- 5.2 bpm) compared with their respective sedentary groups (WKYS: 353.2 +/- 8.5 bpm; SHRS: 412.1 +/- 10.4 bpm; p < 0.001). Exercise training attenuated mean AP only in SHRT (125.9 +/- 6.2 mmHg) vs. SHRS (182.5 +/- 4.2 mmHg, p < 0.001). The WKYT showed a higher vagal effect (Delta HR: 79.0 +/- 2.3 bpm) compared with WKYS (Delta HR: 67.4 +/- 1.7 bpm; p < 0.05). Chronic exercise decreased sympathetic effects on SHRT (Delta HR: -62.8 +/- 2.8 bpm) in comparison with SHRS (Delta HR: -99.8 +/- 9.2 bpm; p = 0.005). The wall thickness of splenic arterioles in SHR was reduced by training (332.1 +/- 16.0 mu m(2) in SHRT vs. 502.7 +/- 36.3 mu m(2) in SHRS; p < 0.05). Conclusions: Exercise training attenuates sympathetic activity and AP in SHR, which may be contributing to the morphological improvement of the splenic arterioles.

The goal of this study was to examine vascular control after sympathetic stimulation by tyramine infusion in hypertensive rats submitted to swimming training. To this end, male rats were assigned to the following groups: sedentary (SN) and trained normotensive (TN), sedentary (SH) and trained hypertensive (TH). Arterial pressure (AP), heart rate (HR), HR variability (HRV), AP variability (APV), and cardiac autonomic function were recorded. Following, infusion of tyramine was administrated. The TN and TH showed a lower resting HR compared with their respective sedentary groups (p < .05). Pressure levels were less in TH than SH (p < .05). The TH showed a higher HRV together with a lower APV in comparison to SH (p < .05). The sympathetic modulation of HRV and APV was lower in TH than in SH (p < .05). Both trained groups presented an increased parasympathetic modulation of HRV compared with their respective sedentary groups (p < .05). The TN and TH groups had a higher vagal effect in comparison with their respective sedentary groups (p < .001). The sympathetic effect was lower in TH than in SH (p < .001). Pressor and HR responses to tyramine in different doses were attenuated in TH (p < .001). Further analysis showed a significant association between infusion of tyramine and normalized LF component of HRV (r = 0.84, p < .001), systolic APV (r = 0.58, p < .001) and diastolic APV (r = 0.49, p < .001). In conclusion, exercise training provokes less pressor response variation by tyramine infusion in hypertensive animals suggesting sympathetic nerve endings adjustments and decrease of the vasoconstrictor effect attenuates injury caused by hypertension improving cardiovascular autonomic dysfunction, which can be associated with sympathetic attenuation.

Introdução: O uso de meias de compressão com o objetivo de otimização do desempenho vem se popularizando de maneira significativa, porém muitas ainda são as perguntas para saber se de fato elas possuem capacidade ergogênica. Objetivo: Avaliar agudamente o uso de meias de compressão (MC) sobre o YoYo intermitente endurance teste 2 (YoYoIE2) e indicadores fisiológicos em futebolistas. Métodos: Oito futebolistas do sexo feminino realizaram de maneira cruzada e randômica o YoYoIE2 usando MC ou meias controle (CON). Resultados: A distância percorrida no YoYoIE2 não diferiu (p=0,11) entre MC (827,5 ± 350 metros) e CON (655 ± 237 metros), mas o tamanho do efeito foi moderado (0,60). O desempenho individual em 75% foi maior usando as MC do que as CON. Percepção subjetiva de recuperação, lactato em repouso e pós teste, frequência cardíaca (FC) pico, FC de recuperação e percepção subjetiva de esforço não diferiram (p>0,05) entre MC e CON. Conclusão: O uso de MC durante exercício intermitente pode ter efeito ergogênico quando considerado o tamanho do efeito moderado e as respostas individuais. Porém as MC parecem não influenciar indicadores fisiológicos e de intensidade associados ao YoYoIE2.