LUANA FARIAS DE OLIVEIRA
Projetos de Pesquisa
Unidades Organizacionais
LIM/17 - Laboratório de Investigação em Reumatologia, Hospital das Clínicas, Faculdade de Medicina
3 resultados
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- The effect of beta-alanine supplementation on high intensity cycling capacity in normoxia and hypoxia(2021) PATEL, Kiran Akshay; OLIVEIRA, Luana Farias de; SALE, Craig; JAMES, Ruth M.The availability of dietary beta-alanine (BA) is the limiting factor in carnosine synthesis within human muscle due to its low intramuscular concentration and substrate affinity. Carnosine can accept hydrogen ions (H+), making it an important intramuscular buffer against exercise-induced acidosis. Metabolite accumulation rate increases when exercising in hypoxic conditions, thus an increased carnosine concentration could attenuate H+ build-up when exercising in hypoxic conditions. This study examined the effects of BA supplementation on high intensity cycling capacity in normoxia and hypoxia. In a double-blind design, nineteen males were matched into a BA group (n = 10; 6.4 g center dot d(-1)) or a placebo group (PLA; n = 9) and supplemented for 28 days, carrying out two pre- and two post-supplementation cycling capacity trials at 110% of powermax, one in normoxia and one in hypoxia (15.5% O-2). Hypoxia led to a 9.1% reduction in exercise capacity, but BA supplementation had no significant effect on exercise capacity in normoxia or hypoxia (P > 0.05). Blood lactate accumulation showed a significant trial x time interaction post-supplementation (P = 0.016), although this was not significantly different between groups. BA supplementation did not increase high intensity cycling capacity in normoxia, nor did it improve cycling capacity in hypoxia even though exercise capacity was reduced under hypoxic conditions.
- Beta-alanine did not improve high-intensity performance throughout simulated road cycling(2022) PERIM, Pedro; GOBBI, Nathan; DUARTE, Breno; OLIVEIRA, Luana Farias de; COSTA, Luiz Augusto Riani; SALE, Craig; GUALANO, Bruno; DOLAN, Eimear; SAUNDERS, BryanThis study investigated the effect of beta-alanine supplementation on short-duration sprints and final 4-km simulated uphill cycling time-trial performance during a comprehensive and novel exercise protocol representative of the demands of road-race cycling, and determined if changes were related to increases in muscle carnosine content. Seventeen cyclists (age 38 +/- 9 y, height 1.76 +/- 0.07 m, body mass 71.4 +/- 8.8 kg, V?O-2max 52.4 +/- 8.3 ml center dot kg(-1)center dot min(-1)) participated in this placebo-controlled, double-blind study. Cyclists undertook a prolonged intermittent cycling protocol lasting 125 min, with a 10-s sprint every 20 min, finishing with a 4-km time-trial at 5% simulated incline. Participants completed two familiarization sessions, and two main sessions, one pre-supplementation and one post-supplementation following 28 days of 6.4 g center dot day(-1) of beta-alanine (N=11) or placebo (N=6; maltodextrin). Muscle biopsies obtained pre- and post-supplementation were analysed for muscle carnosine content. There were no main effects on sprint performance throughout the intermittent cycling test (all P>0.05). There was no group (P=0.69), time (P=0.50) or group x time interaction (P=0.26) on time-to-complete the 4-km time-trial. Time-to-completion did not change from pre- to post-supplementation for BA (-19.2 +/- 45.6 s, P=0.43) or PL (+2.8 +/- 31.6 s, P=0.99). Beta-alanine supplementation increased muscle carnosine content from pre- to post-supplementation (+9.4 +/- 4.0 mmol center dot kg(-1)dm; P<0.0001) but was not related to performance changes (r=0.320, P=0.37). Chronic beta-alanine supplementation increased muscle carnosine content but did not improve short-duration sprint performance throughout simulated road race cycling, nor 4-km uphill time-trial performance conducted at the end of this cycling test.
- 24-Week beta-alanine ingestion does not affect muscle taurine or clinical blood parameters in healthy males(2020) SAUNDERS, Bryan; FRANCHI, Mariana; OLIVEIRA, Luana Farias de; SILVA, Vinicius da Eira; SILVA, Rafael Pires da; PAINELLI, Vitor de Salles; COSTA, Luiz Augusto Riani; SALE, Craig; HARRIS, Roger Charles; ROSCHEL, Hamilton; ARTIOLI, Guilherme Giannini; GUALANO, BrunoPurpose To investigate the effects of chronic beta-alanine (BA) supplementation on muscle taurine content, blood clinical markers and sensory side-effects. Methods Twenty-five healthy male participants (age 27 +/- 4 years, height 1.75 +/- 0.09 m, body mass 78.9 +/- 11.7 kg) were supplemented with 6.4 g day(-1) of sustained-release BA (N = 16; CarnoSyn (TM), NAI, USA) or placebo (PL; N = 9; maltodextrin) for 24 weeks. Resting muscle biopsies of the m. vastus lateralis were taken at 0, 12 and 24 weeks and analysed for taurine content (BA, N = 12; PL, N = 6) using high-performance liquid chromatography. Resting venous blood samples were taken every 4 weeks and analysed for markers of renal, hepatic and muscle function (BA, N = 15; PL, N = 8; aspartate transaminase; alanine aminotransferase; alkaline phosphatase; lactate dehydrogenase; albumin; globulin; creatinine; estimated glomerular filtration rate and creatine kinase). Results There was a significant main effect of group (p = 0.04) on muscle taurine, with overall lower values in PL, although there was no main effect of time or interaction effect (both p > 0.05) and no differences between specific timepoints (week 0, BA: 33.67 +/- 8.18 mmol kg(-1) dm, PL: 27.75 +/- 4.86 mmol kg(-1) dm; week 12, BA: 35.93 +/- 8.79 mmol kg(-1) dm, PL: 27.67 +/- 4.75 mmol kg(-1) dm; week 24, BA: 35.42 +/- 6.16 mmol kg(-1) dm, PL: 31.99 +/- 5.60 mmol kg(-1) dm). There was no effect of treatment, time or any interaction effects on any blood marker (all p > 0.05) and no self-reported side-effects in these participants throughout the study. Conclusions The current study showed that 24 weeks of BA supplementation at 6.4 g day(-1) did not significantly affect muscle taurine content, clinical markers of renal, hepatic and muscle function, nor did it result in chronic sensory side-effects, in healthy individuals. Since athletes are likely to engage in chronic supplementation, these data provide important evidence to suggest that supplementation with BA at these doses for up to 24 weeks is safe for healthy individuals.