Brooks Adrenaline GTS 15 Review

The 15th version is a different shoe altogether when compared to GTS 14.

Like any other shoe model which has been around for many years, your opinion of the GTS 15 will depend on whether you’ve run in its previous version or not. Runners who wear the GTS for the first time will experience a snugly fitting shoe with a firm and stable ride, blended with pronation control manners.

A well rounded shoe if you’re exploring the territory occupied by other alternatives such as the Saucony Guide 8, New Balance 1260V4, adidas Sequence 7 and Nike Structure 18.

Like the GTS 14, this one aims to deliver stability, cushioning and motion control together as a package.

On the other hand, if you’re going one up from the GTS 14, then you will find the ’15 to be a very different animal. The sizing runs half size smaller, upper is much snugger, and the midsole foam isn’t as cushiony as it used to be. At least, that’s the gist of it, although there are other changes which make the GTS 15 what it is.

And what brings about the noticeable change in Adrenaline GTS 15’s character ? Result of quite a few things teaming up together. Since the upper fit has changed drastically, it might be a good idea to warm things up by talking about it first.

Line up both the GTS 14 and 15’s insoles, and the length will be the same. So why the difference in sizing?

Same last markings as 2014 edition. So the last hasn’t changed, either.

We bet one of the first things you’ll notice when you slip into a pair is that the shoe has shrunk by half a size, and also that the forefoot and midfoot fits tighter. Pull out the removable, molded foam insole and measure it against the GTS 14’s. The length is identical, as expected of two shoes which share the same size. We knew this already, but wanted to call out the fact that even in circumstances when the shoe size feels smaller or bigger, the actual length never varies. After all, US 11 is the same across a single brand no matter what, with no empirical deviations. We also believe the last to be the same across, going by markings (BP-104-3) on the insole.

So if the metric length has remained unaltered, what’s causing the shoe to feel smaller?

The heel counter molding has a more pronounced inwards curve, pushing the foot forward. Achilles dip is also firmer owing to the synthetic overlay wrapped higher.

Anything will move forward if force is applied behind it, and that’s exactly what happens inside the GTS 15. Compared to the good ol’ 2014 GTS, the heel counter molding curves more inwards, pushing the foot slightly forward.

That results in a shortage of space ahead of the big toe, and hence making the shoe feel half size smaller. We’ve also seen the reverse apply in some shoes, where an accommodating heel counter has the foot sitting further backwards, and creating room upfront.

1) Forefoot overlay size has been increased on both sides 2) Midfoot side wrap design changed on medial and lateral sides 3) Medial post is much firmer than GTS 14

That’s not end of it. The forefoot has two more updates which increases snugness in that area. First and foremost, both sides have a centimeter wide band of synthetic leather going over the mesh.

That’s not unusual, being standard design practice, but it contrasts greatly with how the GTS 14 was designed. That shoe only had thin strips (see image below) of fused urethane running over, and that too more towards the top of forefoot than on the sides. That helped create some room for splay.

1) Mesh change, and forefoot feels half size smaller 2) Lacing extends further over toe box; lacing gap increased both ways; speed loops introduced in midfoot; laces are now flat. 3) Heel counter is molded inwards, pushing the foot forward into the toe box.

The other thing to take into account here is the change in lacing position. From a functional perspective, the GTS 15’s lacing effectively starts around 5 mm closer to the toe tip than the ’14. And we say functionally because technically the GTS 14’s lacing is closer to the front. If you’re confused, don’t be. The picture above helps us remember what the lacing on the GTS 14 looked like – the first row of lacing was connected to a loop in the front. This eased off the pressure a bit.

Adrenaline GTS 15 doesn’t care for such niceties, and the front row lacing comes minus the loop. This also means that the eyelets are moved forward, moving the lacing pressure with it. As a consequence, the forefoot feels shallower and snugger. There is a workaround for this, though.

If you need more splay room, all you have to do is to skip lacing the first row of eyelets. And if you were thinking that the unused lace portion will end up being too long, fret not. The GTS lace length is optimal, meaning that it doesn’t feel too long even after skipping one row of eyelets. No slapping around the sides. So you can either do that, or go wide (2E) or extra wide (4E)  in the new Adrenaline.

Flat and semi-elastic laces like the Ghost 7, and midfoot lacing is cinched through a set of twin speed loops.

The shoe retains six main rows of lacing (seventh being the back-up one), like the GTS 14. But since the first row is moved forward, lacing rows now have more space separating them. Coupled with that is the increased width between opposing eyelets, and introduction of two speed-lacing loops right in the middle.

The wider spread lacing in both directions puts more top down pressure on the foot, and things like flush fitting speed loops and flat laces (GTS 14 had round ones) only help make the midfoot lockdown more effective.

Lateral midfoot looks cleaner now, with the welded ‘fingers’ gone.

Glossy synthetic of GTS 14 has been interchanged with a perforated panel.

Additional layer of internal lining – only on the arch side.

The lateral side loses the welded cage of the GTS 14, and glossy medial piece of urethane is replaced by a perforated synthetic panel. Makes the ’15 look cleaner visually, not that it makes a difference functionally.

However, all those updates around the lacing area more than compensate for any decrease in snugness these side panel redesigns might have caused.

Left and right pair manufacturing inconsistency. Notice how the right shoe has a shallower forefoot side panel.

Upper of the GTS 15 suffers from the lack of manufacturing finesse which we’ve encountered recently, in shoes like the Ghost 7. In Adrenaline’s instance, the lasting inconsistency is visible on the medial side of upper forefoot. See the dimensional difference of materials rising up from the midsole edge?

It did not cause any problems for us, but we’re putting it up here so people from Brooks can see it. Hopefully.

Tongue is standard design, not attached to the sides. Materials are high specs, soft lining below and spacer mesh on top. It also carries over the very handy ’tongue tied’ loop, which prevents slide. Laces are switched from round and plush to flat and stretchy, same as what’s on the Ghost 7.

We pointed out earlier than the heel counter had an increased inwards curve compared to GTS 14. The collar is snugger fitting as a result, specifically the area around the Achilles.

The materials have also been changed, but no impact from performance viewpoint. Soft dual lining – one type of mesh lining the Achilles and another around either sides.

The Achilles dip is firmer than the GTS 14, as the synthetic leather panels wrap higher over the outside heel. Reflectivity is scaled down on the heel, but increased on the toe-box, which kind of makes it even.

The GTS 15 (right) upper looks higher than the GTS 14’s.

But collar height is the same. Only midfoot stack heights have risen.

When stacked heel to heel, the GTS 15 collar walls appear higher than 14. When the actual height was measured using a scale, it was the same across. It just so happens that the midsole is higher this year, and we have a theory on that.

That theory happens to be this: Brooks’ DNA gel, a midsole cushioning insert last seen on the GTS 14 is now missing, presumed lost forever. In its place is a piece of foam which the Seattle based company calls ‘BioMoGo DNA foam’. Since the actual Gel was more cushioned than foam, Brooks now needs a higher volume of foam to come close to the level of original DNA cushioning, and hence the higher stack height.

Brooks says that the BiMoGo foam is blended with non-Newtonian DNA material. Non-Newtonian materials are those which change density based on how much force you apply on it. These kind of materials are also called ’shear-thickening’ compounds. Brooks also claims the new ‘BioMoGo DNA’ foam to have ’30% more cushioning’ than Gel or regular midsole foams, and ‘twice as much’ energy return.

Except that none of all that is apparent when running in a pair of GTS 15.

BiMoGo might be biodegradable, landfill friendly and all that. Nice job, Brooks. But calling the BMG foam non-Newtonian is utter nonsense. We really don’t care if their laboratory tests showed an infinitesimal amount of shear thickening behavior, because during runs it is not effective. And we know how real non-Newtonian foams behave like. BMW motorrad uses the NP-2 foam in back, elbow and knee protectors, and that, my friend, is the real deal. Not the stiff foam which Brooks claims to possess miraculous powers.

We call vaporware on DNA part of the foam. It is as disappointing as Saucony’s ’new’ Powergrid+ midsole seen on the new Triumph ISO.

Notice the slight color variation between two reds. One in the front is softer, while the darker red is the hard medial post. These foam layers are ‘co-molded’ instead of being glued together.

If you don’t read all that marketing fluff and treat the shoe sans lofty expectations, the GTS 15’s ride is pretty good. The midsole is mildly cushioned, definitely firmer than GTS 14, transition comes smooth. Adrenaline being a pronation control shoe, has four densities of foam, three of them co-molded together without adhesives.

The white foam is a separate piece of foam glued to the rest of the midsole. And like any motion control shoe, the foam layers go soft to hard, progressing from lateral to medial side.

With the midsole no longer featuring a DNA gel embed, Brooks makes some significant changes to the midsole design. The most visible of which would be the foam crash pad on the lateral side. As opposed to the heel only location of the GTS 14 crash-pad, the new foam section spans all the way around from medial midsole to lateral tip.

This is meant to improve transition. Like we mentioned before, the GTS 15 rides smooth, though the difference from a GTS 14 is minimal from an usage perspective. The 2014 model was already a very smooth riding shoe.

Turn the forefoot over to see a dual density construction, moving from a single foam design of the ’14. Again, hard to say whether that results in improved ride, complex midsole engineering nevertheless. The forefoot flexibility is lower this year, more stiffer than the already stiff GTS 14.

Foam density has been made firmer all across, and is another reason why the GTS 15 rides less softer than Adrenaline 14. The removable insole and faux combination board lasting in heel is carried over from 2014. Faux because it isn’t true combination lasting; the thin sheet of cardboard is stuck on to a EVA sheet below. One area where the increased firmness makes itself noticed is the medial post.

Medial posts are firm by nature, yet the one used in GTS 15 is even more so. Crudely put, if the GTS 14’ medial midsole felt as hard as a piece of wood, then the GTS 15’s is a rock. It is also comparatively early stage, meaning it extends further into the heel.

This affects the motion controlling behavior of the shoe, as the harder midsole foam is felt more during transitions versus the GTS 14. But given there’s all around firmness, the pronation control is that of mild intensity, with no lateral lean seen in some shoes such as the New Balance 860 V5.

No lateral lean and firm ride also makes the GTS stable. It is taller than last year’s model, but that has no bearing on stability. The heel feels very grounded, and the flared forefoot does its part in making the front planted.

1) Forefoot midsole is now dual density 2) Midfoot has been filled up with rubber and gets a sleeker profile 3) Crash pad groove position changed

The GTS 15’ outsole maintains a similar layout of rubber and flex grooves, except for two areas. The midfoot shank size is reduced, and the gap is filled with rubber.

Outsole waist has been made slimmer as the rubber pieces sit further away from the edge. This is something which we noticed visually, and did not feel out of sorts during the run.

Secondly, the position of the crash pad groove has shifted further into rear-foot. This helps the heel section break away more efficiently during foot-strikes, and also adds to the cushioning feel. This tries to make up for the loss of DNA gel, somewhat.

Traction has never been an issue with Brooks outsoles. The rubber has good hold, and near complete coverage makes for a grippy pair of running shoes. Now if they could do something about the durability…

The takeaway of all this is that the GTS 15 is a slightly cushioned shoe which offers both stability and motion control, with a snug fitting upper package. It uses top notch materials, everything seems well glued and stitched together. However, existing GTS 14 runners need to know that the shoe has changed, and hopefully, our review has done a fair job of laying it all out for you. Whether you like the Adrenaline 15 or not is a matter of personal choice, but one thing’s for certain – buying half size larger will be warranted in most cases.

We were expecting the shoe to go lighter because of DNA gel disappearing, but that hasn’t happened. The weight is exactly the same as last year, and so is the retail price.

(Disclaimer: For this review, Solereview.com bought the shoe at full US retail price.)

Looking to upgrade your old Adrenaline GTS 14 to the latest version, but not sure how the 2015 model compares? We can help here. The following infographic is a ready-reckoner for what changes you might expect in the new model vs. old. To make this more fun, we’ve put in a system of percentage match, which calculates a weighted average for a set of attributes.

A higher or lower match percentage is neither good or bad. The % number just tells you how similar or distanced the new shoe is from the previous version. Total match % is a result of weighted averages.