While the upper is somewhat traditional, the Spire 2 has decent breathability and width. While not super airy, the mesh around the midfoot and partially the forefoot does fantastic in the hot Southern California temperatures.
There is a decent heel counter in the shoe that wraps about 1.5 inches around each side and goes up all the way up the heel with the exception of some room left for the Achilles tab to flex. There is some minor give to it and combined with the cushion lining of the upper, I have not had any issues with excessive pressure on my calcaneus (heel bone).
The heel and midfoot have fairly normal width to them but there is a little more room in the forefoot without being sloppy. Initially the upper around the forefoot and midfoot were fairly stiff upon try on, but after about 20 miles that loosened up. The heel is held in very well and the Spire 2 is one of the first training shoes I have not had to lace lock to keep my foot from moving excessively.
Due to the initial stiffness I cannot recommend going sockless in the shoe given the few overlays in the forefoot. However with socks this is one of those uppers that you completely forget about on the run.
The 361 Spire 2 will work well for a variety of runners. Specifically this shoe will be a forefoot striker's dream. As I have discussed previously, it is normal during the initial contact phase of running gait for individuals to land on the lateral aspect of their foot/shoe after which point they will pronate to toe-off during terminal stance from more of the medial aspect of the shoe (specifically over the 1st MTP joint barring any gait pathology). The 361 Spire has a very large section of their special midsole material, QU!CKFOAM placed in the lateral forefoot. In the heel aspect of the Spire 2, the QU!CKFOAM acts as a topsole material, but in the lateral and central forefoot it makes up the entire midsole. This lends to fantastic and responsive cushioning for those getting up on their metatarsals.
For those that land farther back, there is a good level of QU!ICKFOAM throughout the lateral aspect of the shoe. QU!CKFOAM lends to a balanced level of cushioning. In the Spire 2 that leans a bit toward firmer and more responsive. So do not go in expecting a super soft shoe. What I was surprised by given that this company has several prior Asics developers working for them is that the posterior lateral heel is actually slightly beveled. While it is very minor and I wish it was a bit more to smooth out a heel landings, it is noticeable compared to more traditional trainers that instead have a rigid posterior heel (specifically Asics).
The flexibility of this shoe in the right places is surprisingly good. The forefoot is very flexible despite the large amount of QU!CKFOAM and feels fantastic at toe-off. The heel and midfoot are obviously not as flexible, but flexibility is generally not needed as much there.
Spec wise the Spire 2 comes in at 10.3 ounces (men's size 9) which is respectable for traditional trainers and not overly heavy. There is an 11mm drop that I personally did not notice but those sensitive to that should be aware of the more traditional design.
Durability wise this shoe stands out. I tend to destroy shoes due to a few issues (namely poor proprioception) but have almost no wear on either the upper or the sole of the Spire 2 after over 100 miles. I would expect to get the traditional 400-500 miles out of this shoe, but other people who run a lighter on their feet can expect to get quite a few more. I am hearing of many people getting 700-800 miles on their pairs because the QU!CKFOAM tends to keep the shoe feeling exactly like it did when first tried on.
Thoughts as a DPT
I discussed the lateral forefoot cushioning above and more specifically in the Chaser Review (HERE) so I would like to discuss something I am not as much of a fan of (even though I have been impressed by the Spire 2).
Midfoot shanks are traditionally used to stiffen up the midfoot portion of the shoe with the hope of reducing torsion and flexion at this point. From a functional standpoint that makes sense and is in line with the fact that there is not a joint in the midfoot that allows normal sagittal plane (front to back) motion. So you do not want the shoe flexing there. My problem with the general design is that a large chunk of the outsole is taken out of the midfoot in most footwear with this attribute. So naturally the shoe will actually be biased to bend more there. The shank will work fine short term, but when it begins to wear down and relax, the shoe will begin to do exactly what the shank was trying to prevent. I have discussed previously how this may irritate people with plantar fasciitis issues given that you are bending the midfoot in a way it the joints do not support. Thus the joints of the midfoot must compensate to make up that motion in extreme ways, which can torque the plantar fascia in ways it does not normally move to get around this roadblock. What I have not discussed is how easy this is to fix. Integrating a shank into the midfoot is a great idea. Just make sure there is also a full ground contact outsole! Yes this will add a bit of weight, but it will make the shoe far more stable and even when the shank begins to wear down, the shoe will not have a major flexion point bias! 361 is starting to move away from doing this as can be seen in some of their other shoes, but many companies like Asics continue to do this. Their traditional shoes like the Cumulus, GT series, Kayano, Nimbus and more continue to have non-continuous outsoles with midfoot shanks that they hope will hold up. To be fair, even Asics has many shoes that are beginning to move away from this and the length of their midfoot shanks are beginning to shorten. So obviously something is up.
What I would love for 361 to do would be to start integrating these shanks into the midsole instead of being separate and leaving a space missing under the midfoot. This is already starting to happen as evident by an integrated shank with full outsole coverage on the lateral aspect of the shoe in 361's traditional stability shoe, the Sensation 2. The 361 KgM 2 and Shield 2 both do not have shanks while their racing shoe the Chaser has a carbon fiber plate integrated into the midsole. So I think they are moving in the right direction.
For those looking for a traditional trainer with fantastic forefoot cushioning, the 361 Spire 2 is going to be one of the better (if not the best) shoes out there. Like my review of the Chaser, I am extremely impressed with QU!CKFOAM as a nice blend between what I was hoping Boost would be without being overly soft. The ride is somewhat firmer but will still keep you protected over longer miles and even some uptempo runs. The Spire 2 is a durable, responsive traditional neutral trainer that should serve you well on a variety of surfaces.
Thanks for reading and don't forget to tack on!
As always, my views are my own. My blog should not and does not serve as a replacement for seeking medical care. If you are currently injured or concerned about an injury, please see your local running physical therapist. If you are in the LA area, I will be taking clients for running evaluations in the future based on my Orthopedic Residency schedule.
Dr. Matthew Klein, PT, DPT
Doctor of Physical Therapy
Casa Colina Orthopedic Resident
***Disclaimer: These shoes were provided free of charge in exchange for a review. I put at least 75 miles on trainers and 25 miles on racing flats. Currently my pair of Spire 2s have 114 miles on them. A big thank you to 361 for sending these to me. These can be found both online and in many local running stores including Top Speed Running if you are in the Inland Empire.