Furthermore , the HT regimen ( i ) enhanced cardiac output ( Q ( H ) ) and perfusion ( Q ( M ) ) / oxygenation of vastus lateralis during exercise ; ( ii ) increased levels of CD34 ( + ) / KDR ( + ) / CD117 ( + ) , CD34 ( + ) / KDR ( + ) / CD133 ( + ) , and CD34 ( + ) / KDR ( + ) / CD31 ( + ) cells in blood ; ( iii ) promoted the proliferative capacity of these CPC subsets , and ( iv ) elevated plasma nitrite/nitrate , stromal cell-derived factor-1 ( SDF-1 ) , matrix metalloproteinase-9 ( MMP-9 ) , and vascular endothelial growth factor-A ( VEGF-A ) concentrations .