Backgrounds-Based on the experience of the cold pressor test(CPT), an increase in coronary blood flow(CBF) is anticipated after sudden cold exposure. Traditionally, WEx has been routinely recommended before cold exposure, however, the physiologic effect of it on the CBF has not been well elucidated. This study was performed to investigate the effect of warming-up exercise (WEx) on the CBF in response to cold exposure. Methods-Fifteen healthy normal males were enrolled. CBFs were assessed by transthoracic Doppler echocardiography at the baseline and after CPT. After the recovery phases, same measurements were repeated with either WEx or weight-bearing Ex(WBEx) before CPT(Fig.A). In the CBF, the time-velocity integral of diastolic flow (Dtvi) was measured with blood pressures and heart rates(HR), and in turn Dtvi x HR was calculated. Results-Dtvi x HR increased significantly after CPT. Increments in Dtvi x HR after WEx was significantly higher than those without WEx (130짹82% vs. 68짹37%, p=0.006). However, increment in Dtvi x HR with WBEx was not significantly different from that without WEx (74짹50% vs. 68짹37%, p=0.46)(Fig.B). Conclusions-WEx can effectively augment the increase in the CBF after cold exposure. However, this phenomenon was not observed in WBEx. These results suggest that WEx better meets the increased physiologic demand imposed by the cold exposure than WBEx. Therefore, WEx, rather than WBEx, should be recommended to give "heart" the chance to prepare itself before cold exposure.