Acute effects of sodium bicarbonate ingestion on cycling time-trial performance: A systematic review and meta-analysis of randomized controlled trials.

This study aimed to investigate the isolated effects of NaHCO on cycling time-trial performance. Furthermore, we investigated whether the ingestion time of NaHCO, standardized or individualized based on time to peak, could be effective in improving cycling time-trial performance. A systematic review was carried out on randomized placebo-controlled studies. A random-effects meta-analysis assessed the standardized mean difference (SMD) between NaHCO and placebo conditions. Eighteen studies were qualitatively (systematic review) and quantitatively (meta-analysis) analysed concerning mean power output (W) ( = 182) and time performance ( = 201). The reviewed studies showed a low risk of bias and homogenous results for W (I = 0%) and performance time (I= 0%). Overall, when compared to placebo, the NaHCO ingestion improved the W (SMD: 0.42; 95% CI: 0.21-0.63;  = 0.001) and performance time (SMD: 0.22; 95% CI: 0.02-0.43;  = 0.03). Similarly, the NaHCO ingestion using a time-to-peak strategy improved the W (SMD: 0.39; 95% CI: 0.03-0.75;  = 0.04; I= 15%) and performance time (SMD: 0.34; 95% CI: 0.07-0.61,  = 0.01, I= 0%). The present findings reveal that NaHCO ingestion has the potential to increase the overall performance time and W in cycling time trials.NaHCO is an effective strategy to increase cycling time-trial performance.The standardized protocol did not improve the cycling time-trial performance parameters.The individualized time-to-peak NaHCO ingestion has a positive effect on time and W during cycling time-trial performance.