BRYAN SAUNDERS
Projetos de Pesquisa
Unidades Organizacionais
LIM/17 - Laboratório de Investigação em Reumatologia, Hospital das Clínicas, Faculdade de Medicina
12 resultados
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- Effects of Sodium Bicarbonate Supplementation on Muscular Strength and Endurance: A Systematic Review and Meta-analysis(2020) GRGIC, Jozo; RODRIGUEZ, Ramon F.; GAROFOLINI, Alessandro; SAUNDERS, Bryan; BISHOP, David J.; SCHOENFELD, Brad J.; PEDISIC, ZeljkoBackground The effects of sodium bicarbonate on muscular strength and muscular endurance are commonly acknowledged as unclear due to the contrasting evidence on the topic. Objective To conduct a systematic review and meta-analysis of studies exploring the acute effects of sodium bicarbonate supplementation on muscular strength and endurance. Methods A search for studies was performed using five databases. Meta-analyses of standardized mean differences (SMDs) were performed using a random-effects model to determine the effects of sodium bicarbonate supplementation on muscular strength (assessed by changes in peak force [N], peak torque [N m], or maximum load lifted [kg]) and muscular endurance (assessed by changes in the number of repetitions performed, isokinetic total work, or time to maintain isometric force production). Subgroup meta-analyses were conducted for the muscular endurance of small vs. large muscle groups and muscular strength tested in a rested vs. fatigued state. A random-effects meta-regression analysis was used to explore possible trends in the effects of: (a) timing of sodium bicarbonate ingestion; and (b) acute increase in blood bicarbonate concentration (from baseline to pre-exercise), on muscular endurance and muscular strength. Results Thirteen studies explored the effects of sodium bicarbonate on muscular endurance and 11 on muscular strength. Sodium bicarbonate supplementation was found to be ergogenic for muscular endurance (SMD = 0.37; 95% confidence interval [CI]: 0.15, 0.59; p = 0.001). The performance-enhancing effects of sodium bicarbonate were significant for both small (SMD = 0.31; 95% CI: 0.04, 0.59; p = 0.025) and large muscle groups (SMD = 0.40; 95% CI: 0.13, 0.66; p = 0.003). Sodium bicarbonate ingestion was not found to enhance muscular strength (SMD = - 0.03; 95% CI: - 0.18, 0.12; p = 0.725). No significant effects were found regardless of whether the testing was carried out in a rested (SMD = 0.02; 95% CI: - 0.09, 0.13; p = 0.694) or fatigued (SMD = - 0.16; 95% CI: - 0.59, 0.28; p = 0.483) state. No significant linear trends in the effects of timing of sodium bicarbonate ingestion or acute increase in blood bicarbonate concentrations on muscular endurance or muscular strength were found. Conclusions Overall, sodium bicarbonate supplementation acutely improves muscular endurance of small and large muscle groups, but no significant ergogenic effect on muscular strength was found.
- Sodium Bicarbonate Supplementation Does Not Improve Running Anaerobic Sprint Test Performance in Semiprofessional Adolescent Soccer Players(2020) GUIMARAES, Rodrigo dos Santos; MORAIS JUNIOR, Alcides Correa de; SCHINCAGLIA, Raquel Machado; SAUNDERS, Bryan; PIMENTEL, Gustavo Duarte; MOTA, Joao FelipeErgogenic strategies have been studied to alleviate muscle fatigue and improve sports performance. Sodium bicarbonate (NaHCO3) has improved repeated sprint performance in adult team-sports players, but the effect for adolescents is unknown. The aim of the present study was to evaluate the effect of NaHCO3 supplementation on repeated sprint performance in semiprofessional adolescent soccer players. In a double-blind, placebo-controlled, crossover trial, 15 male semiprofessional adolescent soccer players (15 +/- 1 years; body fat 10.7 +/- 1.3%) ingested NaHCO3 or a placebo (sodium chloride) 90 min before performing the running anaerobic sprint test (RAST). A countermovement jump was performed before and after the RAST, and ratings of perceived exertion, blood parameters (potential hydrogen and bicarbonate concentration), and fatigue index were also evaluated. Supplementation with NaHCO3 promoted alkalosis, as demonstrated by the increase from the baseline to preexercise, compared with the placebo (potential hydrogen: +0.07 +/- 0.01 vs. -0.00 +/- 0.01, p < .001 and bicarbonate: +3.44 +/- 0.38 vs. -1.45 +/- 0.31 mmol/L, p < .001); however, this change did not translate into an improvement in RAST total time (32.12 +/- 0.30 vs. 33.31 +/- 0.41 s,p = .553); fatigue index (5.44 +/- 0.64 vs. 6.28 +/- 0.64 W/s, p = .263); ratings of perceived exertion (7.60 +/- 0.33 vs. 7.80 +/- 0.10 units, p = .525); countermovement jump pre-RAST (32.21 +/- 3.35 vs. 32.05 +/- 3.51 cm, p = .383); or countermovement jump post-RAST (31.70 +/- 0.78 vs. 32.74 +/- 1.11 cm, p = .696). Acute NaHCO3 supplementation did not reduce muscle fatigue or improve RAST performance in semiprofessional adolescent soccer players. More work assessing supplementation in this age getup is required to increase understanding in the area.
bookPart 1 Citação(ões) na Scopus Biochemistry of buffering capacity and ingestion of buffers in exercise and athletic performance(2020) SAUNDERS, B.; ARTIOLI, G. G.; DOLAN, E.; JONES, R. L.; MATTHEWS, J.; SALE, C.- Is Open-Label Placebo a New Ergogenic Aid? A Commentary on Existing Studies and Guidelines for Future Research(2020) SAITO, Tiemi; BARRETO, Gabriel; SAUNDERS, Bryan; GUALANO, BrunoThe placebo effect has been defined as a genuine psychobiological response that arises from the belief that a positive intervention has been received. However, the notion that belief in an active treatment is necessary to elicit a placebo effect has been challenged. Recent data show that placebo effects may occur even when individuals are openly informed that they are receiving an inert treatment, the so-called open-label placebo. In fact, clinical studies have shown improvements in disease symptoms in patients who underwent an open-label placebo intervention. Now, the application of open-label placebo is attracting interest among the sports science community. Open-label placebo could be a useful and ethically permitted tool to improve exercise performance when applied in combination with other legal ergogenic aids (e.g., nutritional supplements) and/or in place of illegal substances (e.g., anabolic steroids). However, independent laboratories recently investigated the effects of open-label placebo on exercise performance with contrasting results, suggesting that there is much more research required before widespread implementation of open-label placebo in the field of sport and exercise can be justified. Herein we discuss the emerging science on open-label placebo interventions from a clinical setting to sports science. Moreover, we propose a research agenda for investigations on open-label placebo in sports and exercise sciences by covering the main gaps in the field. Addressing the research agenda put forward will help to advance our understanding of this intriguing topic.
- Translation and Validation of the Caffeine Expectancy Questionnaire in Brazil (CaffEQ-BR)(2020) MENDES, Guilherme Falcao; REIS, Caio Eduardo Goncalves; NAKANO, Eduardo Yoshio; COSTA, Teresa Helena Macedo da; SAUNDERS, Bryan; ZANDONADI, Renata PuppinCaffeine is the world's most commonly used stimulant of the central nervous system. Caffeine is present in coffee and other beverages such as tea, soft drinks, and cocoa-based foods. The caffeine expectancy questionnaire was developed to investigate the effects of caffeine expectations and thus contribute to knowledge about its usage and subjective effects (response expectancies). This study aimed to evaluate caffeine expectation psychometrically in a sample of the Brazilian population. The original version of the ""Caffeine Expectancy Questionnaire (CaffEQ)"" was translated and validated into Brazilian-Portuguese and adapted to Brazilian culture to be used in the Brazilian adult (19-59 y) population. After the translation and back-translation processes of the original CaffEQ questionnaire, the content and semantic validation were performed by a group of experts. The Brazilian-Portuguese version of the questionnaire consists of 47 items, in seven factors, which assess subjective perceptions about the effects of caffeine. Interobserver reproducibility and internal consistency of the questionnaire were tested with a convenience sample (n= 50) of Brazilian adult consumers of caffeine sources, who completed the Brazilian CaffEQ (CaffEQ-BR) on two occasions separated by 24 h. All of the 47 questions were adequate regarding reliability, clarity, and comprehension. Psychometric properties could be replicated consistently. Appropriate internal consistency and validation were confirmed by Cronbach's alpha (alpha) 0.948, and an intraclass correlation coefficient of 0.976 was observed. The CaffEQ-BR was applied using a web-based platform to a convenience sample of Brazilian adults from all 27 Brazilian states (n= 4202 participants), along with measures of sociodemographic and caffeine consumption data. Factor validity was verified by confirmatory factor analysis. The seven factors presented a good fit for Root Mean Square Error of Approximation-RMSEA = 0.0332 (95% CI: 0.0290-0.0375). By confirming the validity and reliability of CaffEQ-BR, a useful tool is now available to assess caffeine expectations in the Brazilian adult population.
conferenceObject Sex, But Not Age, Associates With Whole Muscle Carnosine Content Of Trained Men And Women(2020) DOLAN, Eimear; SWINTON, Paul A.; OLIVEIRA, Luana Farias de; REZENDE, Nathalia Saffioti; MAZZOLANI, Bruna Caruso; BESTETTI, Giulia Cazetta; SMAIRA, Fabiana Infante; DUMAS, Alina; PERIM, Pedro; RIANI, Luiz; GUALANO, Bruno; SAUNDERS, Bryan- 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.
- Short-Duration Beta-Alanine Supplementation Did Not Prevent the Detrimental Effects of an Intense Preparatory Period on Exercise Capacity in Top-Level Female Footballers(2020) RIBEIRO, Rafael; DUARTE, Breno; SILVA, Andre Guedes da; RAMOS, Guilherme Passos; PICANCO, Andreia Rossi; PENNA, Eduardo Macedo; COSWIG, Victor; BARBALHO, Matheus; GENTIL, Paulo; GUALANO, Bruno; SAUNDERS, BryanPurpose: High-intensity activity is an important aspect of football performance during competitive match play. The aim of this study was to investigate the effect of beta-alanine supplementation throughout a short-duration intense football-specific training period prior to an international competition on measures of high-intensity running performance. Methods: Twenty-four elite international U20 female footballers (age 18 +/- 1 y, height 1.67 +/- 0.07 m, body mass 62.7 +/- 7.4 kg) volunteered to perform the YoYo Intermittent Recovery Test Level 1 (YoYo IR1), the Running Anaerobic Sprint Test (RAST) and a 20-m maximal sprint test on two separate occasions, separated by 3 weeks of training and supplementation. Participants were randomly assigned to receive either 6.4 g center dot day(-1) sustained-release beta-alanine (BA, N = 12) or an equivalent dose of maltodextrin (placebo, PL, N = 12) throughout a 3-week standardized training camp. Results: There was a main effect of group (P = 0.05) and time (P = 0.004) on YoYo IR1; overall values were lower in PL and distance covered was lower post- vs. pre-supplementation. There was no group x time interaction (P = 0.07). There was an effect of sprint number for RAST, but no further main effects and there were no effect for the 20-m sprint. Conclusions: Top-level female footballers involved in this intense 3-week training period prior to a competition worsened their high-intensity intermittent exercise capacity, and this negative result was not attenuated by a short-duration BA supplementation protocol throughout the same period. Further work is necessary to elucidate whether adapted training protocols and BA dosing regimens could lead to better results.
- Infographic. A systematic review and meta-analysis of the effect of beta-alanine supplementation on exercise capacity and performance(2020) SAUNDERS, Bryan; VIRGILE, Adam; ELLIOTT-SALE, Kirsty Jayne; ARTIOLI, Guilherme Giannini; SWINTON, Paul A.; DOLAN, Eimear; ROSCHEL, Hamilton; SALE, Craig; GUALANO, Bruno
- High dose Nitrate ingestion does not improve 40 km cycling time trial performance in trained cyclists(2020) MOSHER, S. L.; GOUGH, L. A.; DEB, S.; SAUNDERS, B.; NAUGHTON, L. R. Mc; BROWN, D. R.; SPARKS, S. A.This study evaluated the chronic effects of nitrate (NO3-) ingestion over three days, on 40 km TT performance in 11trained cyclists (VO2max: 60.8 +/- 7.4 ml.kg(-1).min(-1); age: 36 +/- 9 years; height: 1.80 +/- 0.06 m; body mass: 87.2 +/- 12.0 kg). Utilising a double-blind randomised cross-over design, participants completed three 40 km TT on a Velotron (R) ergometer following the ingestion of either a 140 ml of ""BEET It sport (R)"" NO3- shot containing 12.8 mmol or 800 mg of NO3-, a placebo drink or nothing (control). Performance, oxygen consumption (VO2), blood bicarbonate (HCO3-), pH and lactate (BLa) and ratings of perceived exertion (RPE) were measured every 10 km throughout the TT. The present findings show that NO3- ingestion had no effect on TT performance (NO3-: 4098.0 +/- 209.8 vs. Placebo: 4161.9 +/- 263.3 s, p = 0.296, ES = 0.11), or VO2 (p = 0.253, ES = 0.13). Similarly, blood lactate and RPE were also unaffected by the experimental conditions (p = 0.522, ES = 0.06; p = 0.085, ES = 0.30) respectively. Therefore, these results suggest that a high dose of NO3- over three days has limited efficacy as an ergogenic aid for 40 km TT cycling performance in trained cyclists.