Effect of oral sodium loading on high-intensity arm ergometry in college wrestlers

Abstract

Purpose: The aim of this study was to examine the effect of 0.3 g x kg(-1) of NaHCO3, 0.21 g x kg(-1) of NaCl, and a low-calorie placebo control (PC) on high-intensity arm ergometry in eight college wrestlers (aged 20.6 +/- 0.8 yr, body mass 70.4 +/- 2.1 kg).

Methods: Subjects performed eight 15-s intervals of maximal effort arm ergometry separated by 20 s of recovery cranking. Treatments were administered in a randomized, double-blind manner in two equal doses at 90 and 60 min before testing. Venous blood samples were withdrawn at baseline, preexercise, and postexercise intervals.

Results: Preexercise pH (7.33 +/- 0.01, 7.31 +/- 0.01, and 7.40 +/- 0.01) and base excess (2.41 +/- 0.35, 0.93 +/- 0.39, and 8.45 +/- 0.51) after PC and NaCl ingestion, respectively, were similar, whereas ingestion of NaHCO3 resulted in significantly higher values (P < or = 0.05). Postexercise pH (7.02 +/- 0.01, 7.02 +/- 0.03, and 7.09 +/- 0.03) and base excess (-13.29 +/- 0.96, -14.49 +/- 1.01, and -8.83 +/- 1.38) were significantly lower after both PC and NaCl ingestion compared with NaHCO3 ingestion. Postexercise plasma [lactate] was also greater in both PC and NaHCO3 trials (21.42 +/- 1.52, 20.07 +/- 1.39, and 22.65 +/- 1.77 mmol x L(-1)). However, peak power (370.7 +/- 26.0, 346.3 +/- 13.6, and 354.3 +/- 18.9 W) and total work accomplished in eight intervals (30.2 +/- 1.5, 29.6 +/- 1.1, and 29.9 +/- 1.1 kJ), and percent fatigue (31.0 +/- 2.7, 29.0 +/- 3.2, and 29.2 +/- 4.0%) were similar.

Conclusions: These data contradict previous reports of ergogenic benefits NaHCO3 and NaCl administration before exercise and further suggest that performance in this type of activity may not be enhanced by exogenously induced metabolic alkalosis or sodium ingestion.