Evaluation Remember the Wave Ekiden from last spring? That was Mizunos audaciously light racing shoe, which squeezed Wave-plate technology into a mere 179g. Maybe its weight scared people off, because the Wave Spacer is its slightly more substantial replacement. Its still a stripped-down shoe, but a thicker midsole surrounds the Wave plate, the upper has slightly heavier overlays, and internal straps support the rearfoot. The other change: the midsole has layers of softer (green) EVA in the rear- and forefoot. Good for short distances if youre a light, efficient runner.