The ride quality hasn’t changed at all, so the upper gets all the new updates. That being said, all changes are design and material related. Little has changed in how the Structure fits.

Turns out I still much prefer Odyssey for fast running, and the loose fit of Structure 21’s heel was even more apparent after being reminded of the snug heel fit of Odyssey. The shoe that it reminded me of most was the Infinity Run 3. Both shoes have heel clips as well as prominent arches but the Structure 25 felt firmer than the Infinity Run 3. The Structure 21 has a softer interior feel than the 18, 19, and 20 due to the updated mesh which also has better breathability. RIDE QUALITY AND BEHAVIOR The firm ride quality is distributed evenly from heel to toe, so the progression feels smooth and efficient. The outsole also has the center groove and the side ‘crash rails’ with multiple grooves – features which also assist transitions. The outsole rubber is laid out in a familiar format. The outer side has the ‘crash rail’ strip with multiple flex grooves, a design first used on the Pegasus 31.The inner straps hug the foot closely, and the newly introduced flat laces pass smoothly through the eyelet straps. Flywire is restricted to the rear, so that takes care of the pressing sensation against the midfoot.

Expect 400 miles of life from the Structure 21, with the wear and tear of the midsole cushioning and outsole happening in a gradual fashion. UPPER FIT AND FEEL The Structure is Nike’s support shoe with a traditional design. This means that the dual-density midsole has a very firm inner side and a slightly less firm outer side. The Structure 20 balanced the two different levels of firmness extremely well. The Structure 21 has an identical midsole, so the ride exhibits the same qualities. DESIGN AND MATERIALS

Nike Structure 25 Verdict

Two shoes from New Balance complement the Structure 21 perfectly. The first is the newly released 1260V7 – a cushioned stability model. The second shoe is the 1500V3, one of our favorite road racers which combine lightweight cushioning with mild support. SIMILAR MID-PRICED SUPPORT SHOES

When I walked around in the Structure 25 for the first time, it was noticeable how much more it felt like a stability trainer than the last 2 versions. There was a prominent arch sensation which wasn’t there since the Structure 19 but it wasn’t painful or uncomfortable.Forefoot strikers will find the ride to be very responsive due to the large Zoom Air bag. Conversely, heel strikers will experience a flat and unresponsive rear-end. A Zoom Air bag also makes the forefoot stiff so runners who want a flexible shoe should bear this in mind.