Individual participant data meta-analysis provides no evidence of individual response variation in individuals supplementing with beta-alanine. [Dataset]

Abstract

Currently, little is known about the extent of inter-individual variability in response to beta-alanine (BA) supplementation, nor what proportion of said variability can be attributed to external factors, or to the intervention itself (intervention response). To investigate this, individual participant data on the effect of BA supplementation on a high intensity cycling capacity test (CCT110%) were meta-analysed. Changes in time to exhaustion (TTE) and muscle carnosine (MCarn) were the primary and secondary outcomes. The files associated with this output

Citation

ESTEVES, G.P., SWINTON, P., SALE, C., JAMES, R.M., ARTIOLI, G.G., ROSCHEL, H., GUALANO, B., SAUNDERS, B. and DOLAN, E. 2021. Individual participant data meta-analysis provides no evidence of individual response variation in individuals supplementing with beta-alanine. [Dataset]. International journal of sport nutrition and exercise metabolism [online], 31(4), pages 305-313. Available from: https://journals.humankinetics.com/view/journals/ijsnem/31/4/article-p305.xml?content=supplementary-materials

• Acceptance Date: Apr 6, 2021
• Online Publication Date: Jun 7, 2021
• Publication Date: Jul 31, 2021
• Deposit Date: Jun 28, 2021
• Publicly Available Date: Jun 28, 2021
• Publisher: Human Kinetics
• DOI: https://doi.org/10.1123/ijsnem.2021-0038
• Keywords: β-Alanine; Performance; Exercise capacity; Individual response; Carnosine; Supplement
• Public URL: https://rgu-repository.worktribe.com/output/1369939
• Publisher URL: https://journals.humankinetics.com/view/journals/ijsnem/31/4/article-p305.xml?content=supplementary-materials
• Related Public URLs: https://rgu-repository.worktribe.com/output/1299512
• Type of Data: PDF, XLSX and accompanying TXT file.
• Collection Date: Sep 30, 2020
• Collection Method: Multi-level distributional Bayesian models were used to estimate the mean and standard deviation of BA and placebo (PLA) group change scores. The relative sizes of group standard deviations were used to infer whether observed variation in change scores were due to intervention or non-intervention related effects. Six eligible studies were identified, and individual data were obtained from four of these. Analyses showed a group effect of BA supplementation on TTE (7.7[95%CrI:1.3 to 14.3 s]) and MCarn (18.1[95%CrI:14.5 to 21.9 mmol·kgDM-1]). A large intervention response variation was identified for MCarn (σ_IR= 5.8 [95%CrI: 4.2 to 7.4 mmol·kgDM-1]); however, equivalent change score standard deviations were shown for PLA (16.1[95%CrI:13.0 to 21.3 s]) and BA (15.9[95%CrI:13.0 to 20.0 s] conditions, with the probability that standard deviation was greater in PLA being 0.64. In conclusion, the similarity in observed change score standard deviations between groups for TTE indicates the source of variation is common and therefore unrelated to BA supplementation, likely originating instead from external factors, which may include, for example, nutritional intake, sleep patterns or training status. To identify eligible studies, the included studies from a previous meta-analysis that investigated the influence of BA supplementation on exercise test performance were screened (Saunders et al., 2017). The full search strategy is described in the previous meta-analysis. Three databases (PubMed, Google Scholar, and Web of Science) were searched using the terms 'β-alanine OR beta-alanine' concatenated with 'supplementation OR exercise OR training OR athlete OR performance OR carnosine' and only double-blinded, placebo [PLA]-controlled trials were selected. The same strategies were repeated in September 2020 to identify any additional studies that had been published in the interim. Aggregate data were extracted from studies that matched our inclusion criteria (Table 1). Authors were contacted to request individual participant data, and these were compiled into a prepiloted Excel spreadsheet.