Your foot bounces off the pavement with the lighter springier fluidride 20 midsole of the gel cumulus 18 this womens running shoe gives your push offs a little extra power day or night you get the same elite performance from this cushioning shoe your foot bounces off the pavement with the lighter springier fluidride midsole extra cushioning comes courtesy of speva and your push offs get a little extra power with a straighter platform under your big toe enjoy a more cushioned