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The purpose of the present study was to examine whether there is synchronization between end tidal CO2 pressure（PETCO2）and tissue oxygen index（TOI）determined by spacially resolved spectroscopy（SRS）after impulse exercise. The impulse exercise was performed at 400 watts for 10 s. PETCO2 was measured by the breath-by-breath method. The data obtained were interpolated into 1-s data using a three-dimensional spine. TOI was measured in the vastus lateralis and gastrocnemius muscles. The sampling frequency of TOI was 1 Hz. The 1-s data for TOI and PETCO2 were analyzed by fast Fourier transform for a period from 5 to 20 min after impulse exercise. Power spectral density（PSD）was calculated. TOI oscillated before impulse exercise and then suddenly decreased and overshot after the exercise. After about 5 min of recovery, TOI oscillated in the two muscles. For TOIs in the two muscles, there were two peaks in PSD. This indicated oscillations of TOIs in the two muscles. There was synchronization between TOIs in the two muscles. However, PETCO2 did not clearly show oscillation. Cross power spectra （CPS） were obtained between TOIs in the two muscles. There were two peaks of CPS. The slow peak was 0.0034 ± 0.0022 Hz and fast peak was 0.0076 ± 0.0025 Hz. It was concluded that there was synchronization between TOIs in the vastus lateralis and gastrocnemius. However, this synchronization was not induced by P ETCO2 fluctuation.