We spent months logging at least 15 miles per shoe, mixed between short, long, slow, and fast. We considered different strides and foot strikes to see what transpires after a good bit of rubbing and pounding. We hit trails, sandy beaches, granite staircases, and steep mountain roads, but most of the miles came from open, flat roads, where road runners spend the majority of their time.
These running shoes have been put through our rigorous standard of testing month after month. We did the dirty work for you, exposing without bias each model to the trial of miles, logging dozens of trips, and putting in a heavy dose of extracurricular abuse.
Responsiveness can mean different things to different runners, but for us, it falls into two areas of performance. The first is the bounce of the midsole. It's pretty clear how you make this determination — you run. A lot. We also do a ton of side-by-side testing, sometimes running in two different models that have similar bounce so we can get a better idea of which one does the job better.
The other major area tends to be in the upper. Support structures and the overall design can improve the way the shoe adheres to the foot, flexes, and snaps back into shape. Some running shoes, especially stability models, will also imbed posts or rigid lateral structures in the midsole to whip it back to form. Within the upper itself, you'll typically see heel counters and various types of latticing to keep the shoe taut. We pay close attention to fit and the energy expended in each stride. Are we struggling against a sloppy shoe, or is it clean? Is it working with our gait, or is it getting in the way? Is it a hoof or a boot?
To get this measure right, it's important that you're not fighting against a shoe, slipping around, or getting that sloppy shuffle effect that can happen with the big shoes that are a little too comfortable. Much like responsiveness, we pay attention to the way the shoe adheres to the foot, its molding and footbed, and the way the stability structures (like heel counters) shape the gait.
Underfoot we compare foam densities and their pop or squish. Some shoes can be clunky with marshmallow midsoles, while others can be super fast with soles that pop. That's usually to do with the density and thickness of their midsole material. Of course, poor design — like too much arch support — can also sap the energy out of your stride and slow you down. We put in proper miles, jump around and kick walls and stomp on rocks like complete morons, run out in public in two different shoe styles, and poke, prod, and bend to tease these details out. Oh, and we research materials and product complaints like respectable adults too.
This is a really straight forward measure to test. Food scale, meet shoe. Shoe, meet food scale. Of course, we dig a little deeper here. We want to figure out what makes a shoe light or heavy, and we look to see the trade-offs. If the new upper material is Spartan, what's being sacrificed here? Is it worth it to save a quarter of an ounce if the resulting shoe frays and tears at the toe? Probably not.
To get at the durability of our running shoes, we get to have a little fun. This is where we test abrasion resistance and see what happens when different parts of the shoe are pierced and pulled apart. Most of the poking and prodding happens here. "How tough is that glue?" We also do our material research and look at complaints to see if we can find any trends. While we might not be able to put in a full season of marathon training in each shoe, someone probably has, and if we find a pattern of deteriorating midsoles, we'll investigate, and you'll hear about it and whether or not we could replicate that issue along with any advice we feel is helpful.
Pillows. We're looking for pillows here. Well, not always. In fact, we find a lot of times that the models stuffed with cushion turn out to lose their comfort as the miles pass by. That's why you'll find a lot of endurance shoes tend to be light on padding, opting instead for leaner, lighter uppers with a closer fit.
We put in our miles and investigate complaints about features that bug other runners. Our feet might not be picking up a hotspot, so we'll look at that if we see trends. The same with heel cups. Sometimes a loose heel is just universal, but other times it's the heel shape of the runner that's just not catching, so we look at that too.
When we test for this measure, we do our best to run at the same time of day — the hot ass mid-afternoon. The goal is to try to be uncomfortable to see how the feet sweat and air out. We'll grade the shoes and then start digging to see what could be contributing to the performance. Is it mesh, is it a sockliner? Are there lots of impermeable plastic pieces meant to improve support that are also trapping sweat and holding in heat? Is it just lots of friction from excess material rubbing against other loose bits of material? Eventually, we can pull it all apart and assign justified scores with our advice on best uses.