Effect of manipulation of fatigue sense on ventilatory response during recovery after intense exercise

ABSTR A C T BACKGROUND: The aim of this study was to determine the effect of manipulation of fatigue sense on ventilatory response during recovery after intense exercise and ventilatory compensation, that could alter plasma pH level. We ex-amined the effects of eye closure on perceived fatigue sense, plasma pH, and ventilatory response. METHODS: Nine subjects performed intense exercise tests that followed period of 90 s of maximal work rate and 10 min recovery in a closed eyed condition or an open eye control condition. Intense exercise tests were performed using a bicycle ergometer in a semi-recumbent position. RESULTS: Significant difference was not observed in the plasma pH level after intense exercise under the two condi-tions. The degree of recovery for fatigue sense of the leg was significantly (P<0.05) faster in the closed eyed condition than in the control condition, and the effect size was observed to be large (d=0.83). Integrated ventilatory response was significantly (P<0.05) lower in the closed eyed condition than in the control condition during the last 5 minutes of recov-ery. Moreover, the effect size was observed to be large (d=1.11). CONCLUSIONS: The ventilatory response during recovery was affected by changes in fatigue sense and light hypoven-tilation that were elicited by eye closure when it was compared with the control condition while pH homeostasis remained unaffected.