Sodium bicarbonate ingestion does not alter the slow component of oxygen uptake kinetics in professional cyclists

We examined the effects of pre-exercise sodium bicarbonate (NaHC[O.sub.3]) ingestion on the slow component of oxygen uptake (V[O.sub.2]) kinetics in seven professional road cyclists during intense exercise. One hour after ingesting either a placebo or NaHC[O.sub.3] (0.3 g*kg body [mass.sup.-1]), each cyclist (age, 25 [+ or-] 2 years; V[O.sub.2max], 74.7 [+ or-] 5.9 ml.[kg.sup.-l]*[min.sup.-1]; mean [+ or-] s) performed two bouts of 6 min duration at an intensity of 90% V[O.sub.2max] interspersed by 8 min of active recovery. Gas exchange and blood data (pH, blood lactate concentration and [HC[O.sup.-.sub.3]]) were collected during the tests. In both bouts, the slow component of V[O.sub.2] was defined as the difference between end-exercise V[O.sub.2] and the V[O.sub.2] at the end of the third minute. No significant difference was found in the slow component of V[O.sub.2] between conditions in the first (NaHC[O.sub.3], 210 [+ or-] 69 ml; placebo, 239 [+ or-] 105 ml) or second trial (NaHC[O.sub.3], 123 [+ or-] 88 ml; placebo, 197 [+ or-] 101 mi). In conclusion, pre-exercise NaHC[O.sub.3] ingestion did not significantly attenuate the V[O.sub.2] slow component of professional road cyclists during high-intensity exercise