madman
Super Moderator
Abstract
Background: Athletes are increasingly exploring ways to enhance their physical performance. Increasing blood flow to the working tissues through endothelium-dependent vasodilation is one factor athletes use to realize these results. Sports supplements such as pre-workouts tout this benefit; however, many have not been tested under laboratory conditions to examine the effects of commonly used supplements on vasodilation. Two popular supplements are Nitrosigine® and citrulline malate (CM). Thus, the purpose of this experiment was to determine the effective of Nitrosigine and CM on vasodilation using ultrasound and flow mediated dilation (FMD).
Methods: Healthy, normotensive, and physically active male (n = 16) and female (n = 8) young adults participated in the present investigation. We utilized a randomized, double-blind, within-subjects design where participants reported for three trials, each preceded by a 7-day washout period. Baseline FMD measurement was obtained for each visit, followed by consumption of one clinical dose CM (8 g), Nitrosigine (1.5 g), or dextrose placebo (8 g). Following a 60-min digestion period, FMD was repeated. Supplementation order was randomized controlling for potential order effects.
Results: Repeated measures ANOVA yielded a significant supplement (3) x time (2) effect (p < .001), such that Nitrosigine and CM yielded a greater improvement in FMD response than placebo. After supplementation, Nitrosigine and CM increased FMD by 31 and 34%, respectively, compared to a decrease of 2% during the placebo trial. After allometric scaling of the FMD values, supplement x time effect remained significant (p = .001) and changes were similar to non-scaled results. Nitrosigine (23%) and CM (25%) generated significantly greater allometric scaled FMD values when compared to the placebo trail (0.60%).
Discussion: Both Nitrosigine and CM increased endothelial-dependent vasodilation as measured by a change in FMD. Increased vasodilation leads to an increase in skeletal muscle blood flow resulting in potential improvements in exercise performance.
Conclusions
Results from this study support a novel finding that acute supplementation with CM and Nitrosigine can improve endothelial-dependent vasodilation in trained young adults. Prior to this study, there was no comparison of CM and Nitrosigine effects using FMD. This study supports previous research findings that Nitrosigine may be a beneficial pre-workout supplement, and that a 1.5 g dose of Nitrosigine may be equally as effective at increasing endothelial response as a larger 8 g dose of CM.
Background: Athletes are increasingly exploring ways to enhance their physical performance. Increasing blood flow to the working tissues through endothelium-dependent vasodilation is one factor athletes use to realize these results. Sports supplements such as pre-workouts tout this benefit; however, many have not been tested under laboratory conditions to examine the effects of commonly used supplements on vasodilation. Two popular supplements are Nitrosigine® and citrulline malate (CM). Thus, the purpose of this experiment was to determine the effective of Nitrosigine and CM on vasodilation using ultrasound and flow mediated dilation (FMD).
Methods: Healthy, normotensive, and physically active male (n = 16) and female (n = 8) young adults participated in the present investigation. We utilized a randomized, double-blind, within-subjects design where participants reported for three trials, each preceded by a 7-day washout period. Baseline FMD measurement was obtained for each visit, followed by consumption of one clinical dose CM (8 g), Nitrosigine (1.5 g), or dextrose placebo (8 g). Following a 60-min digestion period, FMD was repeated. Supplementation order was randomized controlling for potential order effects.
Results: Repeated measures ANOVA yielded a significant supplement (3) x time (2) effect (p < .001), such that Nitrosigine and CM yielded a greater improvement in FMD response than placebo. After supplementation, Nitrosigine and CM increased FMD by 31 and 34%, respectively, compared to a decrease of 2% during the placebo trial. After allometric scaling of the FMD values, supplement x time effect remained significant (p = .001) and changes were similar to non-scaled results. Nitrosigine (23%) and CM (25%) generated significantly greater allometric scaled FMD values when compared to the placebo trail (0.60%).
Discussion: Both Nitrosigine and CM increased endothelial-dependent vasodilation as measured by a change in FMD. Increased vasodilation leads to an increase in skeletal muscle blood flow resulting in potential improvements in exercise performance.
Conclusions
Results from this study support a novel finding that acute supplementation with CM and Nitrosigine can improve endothelial-dependent vasodilation in trained young adults. Prior to this study, there was no comparison of CM and Nitrosigine effects using FMD. This study supports previous research findings that Nitrosigine may be a beneficial pre-workout supplement, and that a 1.5 g dose of Nitrosigine may be equally as effective at increasing endothelial response as a larger 8 g dose of CM.
