Chronic sodium bicarbonate ingestion affects training adaptations during severe exercise training

Abstract

1410 PURPOSE: The purpose of this study was to determine the effects of sodium bicarbonate ingestion (NaHCO3) during training, on changes in severe intensity exercise tolerance and aerobic and anaerobic capacity. METHODS: Sixteen active, but not well-trained females participated in this study. Tests consisted of a graded exercise test to determine VO2peak and lactate threshold (LT) followed ∼48 h later by an exercise tolerance test (ET; total work completed at pre-training VO2peak intensity). Muscle biopsies (Vastus lateralis) were taken immediately before and after the ET to determine muscle metabolites, anaerobic yield of ATP and muscle buffer capacity (βmin-vitro). After initial testing the subjects were randomly assigned (matched on LT and ET) to one of two training groups. Each matched pair performed the same amount of total work, however the experimental group ingested NaHCO3, (0.4 g·kg−1) while the control group ingested a placebo (NaCl, 0.2 g·kg−1) prior to each training session. Training involved 6–12, 2-min high-intensity intervals (140–180% LT; 1 min rest), 3 × wk for 8 weeks. RESULTS: Both groups significantly increased total work completed during the ET and LT (P<0.05). However, the NaHCO3 group had significantly greater improvements than the NaCl group in total work (160% v 126%; P<0.05) and LT (26% v 15%; P<0.05). Both groups also had significant improvements in βm in-vitro(∼10%; P<0.05) and VO2peak (∼20%; P<0.05), with no significant differences between groups…