The aim of this study is to examine the influence of vocal training on internal respiration in order to develop an efficient method of singing phonation. Five males trained singers (age:$25.0{pm}1.4years$, career:$6.8{pm}1.1;years$) and five female trained singers (age:$22.0{pm}1.0years$, career:$5.8{pm}1.2;years$) participated in this study. $SaO_2$(Oxi Hemoglobin saturation) was measured by Oxy-Pulse meter while $P_ACO_2$ (Pressure Alveolar $CO_2$) was measured by Quick et $CO_2$ before and after 2-minute, 4-minute and 6-minute vocal training. Result showed that $SaO_2$ was within a normal range after vocal training but $P_ACO_2$ came out lower than the normal range (36-40mmHg) after vocal training which led to Hypocapnia. This caused the singers to experience some headache and dizziness.