xtracellular Buffering Supplements to Improve Exercise Capacity and Performance: A Comprehensive Systematic Review and Meta-analysi

Author(s)

de Oliveira, Luana Farias ^[1] ; Dolan, Eimear ^[1] ; Swinton, Paul A. ^[2] ; Durkalec-Michalski, Krzysztof ^{[3, 4]} ; Artioli, Guilherme G. ^[5] ; McNaughton, Lars R. ^[6] ; Saunders, Bryan ^{[7, 1, 3]}

Affiliation

^[1] Univ Sao Paulo, Fac Med FMUSP, Div Rheumatol, Appl Physiol & Nutr Res Grp, Sao Paulo - Brazil

^[2] Robert Gordon Univ, Sch Hlth Sci, Aberdeen - Scotland

^[3] Poznan Univ Phys Educ, Dept Sports Dietet, Poznan - Poland

^[4] Poznan Univ Life Sci, Dept Human Nutr & Dietet, Poznan - Poland

^[5] Manchester Metropolitan Univ, Dept Life Sci, John Dalton Bldg, Manchester M1 5GD, Lancs - England

^[6] Edge Hill Univ, Dept Sport & Phys Act, Sports Nutr & Performance Grp, Ormskirk - England

^[7] Univ Sao Paulo, Inst Orthopaed & Traumatol, Fac Med FMUSP, Sao Paulo - Brazil

• Document type: Review article
• Source: SPORTS MEDICINE; v. 52, n. 3 OCT 2021.
• Web of Science Citations: 0

Abstract

Background Extracellular buffering supplements {[}sodium bicarbonate (SB), sodium citrate (SC), sodium/calcium lactate (SL/CL)] are ergogenic supplements, although questions remain about factors which may modify their effect. Objective To quantify the main effect of extracellular buffering agents on exercise outcomes, and to investigate the influence of potential moderators on this effect using a systematic review and meta-analytic approach. Methods This study was designed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three databases were searched for articles that were screened according to inclusion/exclusion criteria. Bayesian hierarchical meta-analysis and meta-regression models were used to investigate pooled effects of supplementation and moderating effects of a range of factors on exercise and biomarker responses. Results 189 articles with 2019 participants were included, 158 involving SB supplementation, 30 with SC, and seven with CL/SL; four studies provided a combination of buffering supplements together. Supplementation led to a mean estimated increase in blood bicarbonate of + 5.2 mmol L-1 (95% credible interval (CrI) 4.7-5.7). The meta-analysis models identified a positive overall effect of supplementation on exercise capacity and performance compared to placebo {[}ES0.5 = 0.17 (95% CrI 0.12-0.21)] with potential moderating effects of exercise type and duration, training status and when the exercise test was performed following prior exercise. The greatest ergogenic effects were shown for exercise durations of 0.5-10 min {[}ES0.5 = 0.18 (0.13-0.24)] and > 10 min {[}ES0.5 = 0.22 (0.10-0.33)]. Evidence of greater effects on exercise were obtained when blood bicarbonate increases were medium (4-6 mmol L-1) and large (> 6 mmol L-1) compared with small (<= 4 mmol L-1) {[}beta(Small:Medium) = 0.16 (95% CrI 0.02-0.32), beta(Small:Large) = 0.13 (95% CrI - 0.03 to 0.29)]. SB (192 outcomes) was more effective for performance compared to SC (39 outcomes) {[}beta(SC:SB) = 0.10 (95% CrI - 0.02 to 0.22)]. Conclusions Extracellular buffering supplements generate large increases in blood bicarbonate concentration leading to positive overall effects on exercise, with sodium bicarbonate being most effective. Evidence for several group-level moderating factors were identified. These data can guide an athlete's decision as to whether supplementation with buffering agents might be beneficial for their specific aims. (AU)

• FAPESP's process: 19/25032-9 - The role of carnosine on Ca2+ handling, control of oxidative stress and protection against protein glycation: advances and applications of the study life without carnosine
• Grantee: Hamilton Augusto Roschel da Silva
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/26899-6 - The bone response to exercise a translational research program exploring clinical and mechanistic aspects
• Grantee: Eimear Bernadette Dolan
• Support Opportunities: Scholarships in Brazil - Young Researchers
• FAPESP's process: 16/50438-0 - Nutritional suplementation and exercise to optimize exercise performance: focus on individual responses and a step towards personalized sports nutrition
• Grantee: Bryan Saunders
• Support Opportunities: Research Grants - Young Investigators Grants