Brooks reformulated its bouncy DNA AMP foam to make it 20 percent lighter than before without sacrificing any of the springiness that made it a star. The new composition still provides soft landings and energetic takeoffs.Designers topped the Levitate 4 with a newly engineered Fit Knit upper. The new upper is lighter, softer and more breathable than before, giving the shoe a sock-like fit and feel.Underneath, Brooks used an updated arrow-point pattern on the outsole that inspires quick transitions and a little more pop on toe-off. With a slate of upgrades, the women's Brooks Levitate 4 is the best one yet.