The Topo Athletic Ultrafly is best for runners looking for a low foot drop shoe with anatomic foot shape and significant cushioning for high mileage training. Its most comparable competitor in our test group is the Altra Torin 2.5; side by side, the Ultrafly has a more breathable upper and a more rugged outsole, but the Torin has a flatter (zero drop) platform and better energy return in the midsole.
Fit Topo’s anatomic last provides plenty of room for full splay, but stays nicely contoured through the midfoot, with a secure heel fit. The traditional lace system and extensive overlays on the Ultrafly secure the foot well, and the laces hold tension nicely during high mileage. Our test pairs felt true to size, but the company recommends sizing up by half if you are between sizes.
Comfort With the highest stack heights in the Topo lineup, there’s no shortage of cushioning underfoot to absorb road impact with the Ultrafly. Padding around the ankle collar is moderate and rides comfortably, and the uppers breathe and dry nicely despite the multitude of overlays. The roomy and high toe box prevents any risk of toe chafing or hot spots up front.
Responsiveness The primary midsole EVA in the Ultrafly has a soft feel to it and absorbs energy nicely, but there’s very little “pop” or springiness in return. Thanks to a relatively low foot drop, transition from heel to toe is much more efficient for midfoot strikers than for heel strikers.
Ride Quality Each of the three EVA midsole materials of the Ultrafly has different densities, in an effort to guide the foot smoothly through a natural forward motion. In addition to the primary midsole EVA discussed above, there is a firm medial EVA positioned below the arch that functions like a medial post that tapers smoothly at the front and back. In the lateral heel area, a softer EVA is intended to give way and accommodate the “correction” of the firm midsole – but if you’re a heel striker, this only worsens the dynamic of a soft landing without appreciable energy transfer.
Speed The 5mm platform facilitates fast running form with forward weight shift and midfoot striking, but poor midsole responsiveness and relatively heavy material construction significantly limit the speed potential of the Ultrafly.