beta-alanine supplementation to improve exercise capacity and performance: a systematic review and meta-analysis

Autor(es)

Saunders, Bryan ; Elliott-Sale, Kirsty ; Artioli, Guilherme G. ; Swinton, Paul A. ; Dolan, Eimear ; Roschel, Hamilton ; Sale, Craig ; Gualano, Bruno

• Tipo de documento: Artigo de Revisão
• Fonte: BRITISH JOURNAL OF SPORTS MEDICINE; v. 51, n. 8, p. 658+, APR 2017.
• Citações Web of Science: 48

Resumo

Objective To conduct a systematic review and meta-analysis of the evidence on the effects of beta-alanine supplementation on exercise capacity and performance. Design This study was designed in accordance with PRISMA guidelines. A 3-level mixed effects model was employed to model effect sizes and account for dependencies within data. Data sources 3 databases (PubMed, Google Scholar, Web of Science) were searched using a number of terms ('beta-alanine' and `Beta-alanine' combined with `supplementation', `exercise', `training', `athlete', `performance' and `carnosine'). Eligibility criteria for selecting studies Inclusion/exclusion criteria limited articles to double-blinded, placebo-controlled studies investigating the effects of beta-alanine supplementation on an exercise measure. All healthy participant populations were considered, while supplementation protocols were restricted to chronic ingestion. Cross-over designs were excluded due to the long washout period for skeletal muscle carnosine following supplementation. A single outcome measure was extracted for each exercise protocol and converted to effect sizes for meta-analyses. Results 40 individual studies employing 65 different exercise protocols and totalling 70 exercise measures in 1461 participants were included in the analyses. A significant overall effect size of 0.18 (95% CI 0.08 to 0.28) was shown. Meta-regression demonstrated that exercise duration significantly (p=0.004) moderated effect sizes. Subgroup analyses also identified the type of exercise as a significant (p=0.013) moderator of effect sizes within an exercise time frame of 0.5-10 min with greater effect sizes for exercise capacity (0.4998 (95% CI 0.246 to 0.753)) versus performance (0.1078 (95% CI -0.201 to 0.416)). There was no moderating effect of training status (p=0.559), intermittent or continuous exercise (p=0.436) or total amount of beta-alanine ingested (p=0.438). Co-supplementation with sodium bicarbonate resulted in the largest effect size when compared with placebo (0.43 (95% CI 0.22 to 0.64)). Summary/conclusions beta-alanine had a significant overall effect while subgroup analyses revealed a number of modifying factors. These data allow individuals to make informed decisions as to the likelihood of an ergogenic effect with beta-alanine supplementation based on their chosen exercise modality. (AU)

• Processo FAPESP: 14/11948-8 - Vida sem carnosina: desenvolvimento e caracterização de um modelo de rato nocaute para estudo do papel fisiológico da carnosina e suas implicações para o exercício físico e metabolismo muscular
• Beneficiário: Guilherme Giannini Artioli
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 15/11328-2 - Metabolismo da carnosina no músculo esquelético: um estudo de múltiplas abordagens. Sub-estudo 3: explorando o papel da carnosina no músculo esquelético
• Beneficiário: Eimear Bernadette Dolan
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/14746-4 - Metabolismo da carnosina no músculo esquelético: um estudo de múltiplas abordagens
• Beneficiário: Bruno Gualano
• Modalidade de apoio: Auxílio à Pesquisa - Temático