Danner 2650 Hiking Shoes – BPL Feedback?

[JCH]

Well, I was hoping it lasts longer than most trail runners.

Well that would certainly be a big positive.  Hope to see some real-world usage reports on this one.  The exposed seams (look like they are taped or covered with something?) might be a concern…or maybe they are super beefy and last forever 🤷‍♂️

[Stumphges]

Tried these on in wide width today. Nice shoe, felt supportive and flexible, which is not an easy combination of features. You can tell these were designed by a company that’s been making boots and shoes for a while.

But toe box was too pointy for me, and, as David T. pointed out, the sole extends backward of the heelcup. Ecco figured out that soles should be “undercut,” as Dave says, about 20 years ago, and many shoes are now undercut, sometimes dramatically so. An ‘overcut’ shoe, like this one, results in an external plantarflexion torque being applied by the shoe to the ankle joint, such that the foot will have a tendency toward slapping the ground. Obviously, this can be countered by the wearer, but such requires local (shin muscle activity) and maybe global (hip and knee joint) compensations that are undesirable, at least for me.

[JCH]

@stumphges (and anyone else for that matter)…

What “undercut” light hikers do you like/recommend? I find that design to be somewhat uncommon.

[Sean P]

Asolo made a series of shoes like that some years ago, not sure if they still do.
<p style=”text-align: left;”>I haven’t heard that theory on excessive plantarflexion before.</p>
I can’t see how flexion would be altered by this design as I think that is more a consequence of the amount of ‘drop’ in a sole unit.  The more drop, the more plantar flexion.  Women s high heels being the extremity of this design.

[Stumphges]

Sean, an “undercut” heel would not necessarily tend to decrease the magnitude of plantarflexion (what might be termed plantarflexion excursion in the biomechanical literature), but rather reduce the shoe reaction force in the direction of plantarflexion. A traditional shoe heel extends much further back than the point of first contact on an unshod heel. Therefore, the heel of a traditional shoe serves as a long lever arm that exerts an external plantarflexory torque on the ankle joint axis. This is similar to the pronatory torque exerted on the subtalar joint by a wide and rigid shoe heel. Here the pronation excursion may not change, but the speed of pronation (which is correlated with injury risk) probably will, unless countered by compensatory internal torques (e.g. by invertor muscles).

I think undercut heels offer a bit comfort advantage on the downhill, in particular. Going downhill, the shin muscles must counter the greater plantarflexory torque on the ankle by the ground. Overcut or traditional heels make this situation more pronounced, and undercut heels feel much smoother and easier to me.

Ecco long ago pointed out that the average plantflexion angle in unshod gait is around 20 degrees, and so they sloped the bottom of the heel accordingly so that the back portion of the heel would not hit the ground earlier than the heel itself. Many companies have since followed suit. Even a company like Alta does this on many models. Hoka does it. Oboz, as David showed above, has it as a distinctive design feature. I consider it a requirement in a shoe at this point. It seems to me that some traditional shoe companies don’t do it, perhaps due to intellectural inertia, and some companies are actually making overcut heels for reasons I can’t imagine.

[Sean P]

I can only find one study that looks at this and the results were:

Effects of heel flare
Only one included article (Table 3, Figure 2) investigated the effects of heel flare construction (lateral heel flare of 25°, no lateral heel flare 0°, rounded heel) on running biomechanics. However, there were no significant differences in tibiocalcaneal and ankle kinematics (initial inversion, maximal eversion velocity) among heel flare conditions (Stacoff et al., 2001).

 

From Stacoff et al (2001):

It was expected that the large lever of the flared shoe sole would produce the largest eversion velocity and that the decreased lever of the round sole the smallest. This was not the case and is in contrast to previous investigations using shoe markers, where it was concluded that prominent lateral heel flares cause an increased initial eversion or eversion velocity . It was further expected that the flare of the shoe sole would increase maximum shoe eversion and the round shoe sole would decrease maximum shoe eversion. However, all subjects had the largest maximum eversion with the round shoe and the smallest maximum eversion with either the flared sole or the straight sole. It is speculated that i) the prominent lateral flare compressed considerably during touchdown hereby reducing the acting lever and that ii) the hard outer sole of the round shoe deformed very little, which may have favored a rolling action of the foot, resulting in a large maximum eversion. Future investigations may want to establish the change of lever length over time of various shoe sole modifications to clarify this issue.

I am not stating that you are incorrect – there are likely to be further additional studies, this one I have cited was a small study and looked at running, not walking, biomechanics  but I am always wary when someone makes definitive statements (especially if a shoe company is involved).

I am not not looking for an argument, I am genuinely curious about this, having a couple of pairs of shoes with undercut soles.

If you have any studies I would welcome the links.

[Stumphges]

Hi Sean,

I haven’t looked at this for some time, and I don’t have time to look through studies at the moment. Sorry, don’t mean to dodge. But perhaps consider that, as I mentioned above, external moments can be countered by compensatory internal moments, and that might be what happened here; indeed, it may be that the internal moments were over-compensations, given that the largest maximum eversion seemed to correlate with the round-heeled shoe. The authors seem to suggest as much: “It is concluded that the tibiocalcaneal kinematics of running may be individually unique and that shoe sole modifications may not be able to change them substantially.” If so, those compensations (which could be viewed as the body’s resistance to the shoe changing its default, or “preferred” as Beno Nigg would say, running pattern), be they local or more proximal, could result in fatigue, discomfort, etc.

Also note that I offered lateral heel flare and calcaneal eversion as an analog of the effects of posterior heel flare and its opposite on ankle plantarflexion. Have you walked downhill in a shoe with a rounded heel? I find it feels different, and that I exprience less anterior shin fatigue and knee irritation. Of course, anecdotes of this kind are not very good evidence, but on the other hand, when dealing with such complex biomechanical questions, particularly as they inevitably get into the interplay of external and internal moments and “preferred movement paths,” subjective experience of comfort or discomfort is kind of the most relevant thing. It’s also possible that I’m totally wrong about all this stuff, and that this study suggests that Oboz’s rounded heel, though it may reduce the number of pebbles that end up in the shoe, may also, and counterintuitively, produce slightly greater calcaneal eversion in some people.

Here is a list of papers published since 2017 that cite Stacoff 2001: https://scholar.google.com/scholar?as_ylo=2017&hl=en&as_sdt=5,24&sciodt=0,24&cites=8774174868569919887&scipsc=

 

[Bowen D]

I just got back from 4 nights + 7 nights in the high Sierra wearing the Danner 2650’s in 10.5E and I loved the shoes. Perfect balance between cushy and springy like a trail runner, but more supportive and, I think, way more durable. I did 85 miles or so, 2/3 on trail and 1/3 off trail, and the shoes worked really really well. I would have loved more sticky rubber, but of course I realize that’s a trade-off with sole durability. Really happy with these shoes so far!

[Matthew / BPL]

Did you get them wet? How did they dry? I think these look good but I like having my feet dry quickly after a wet-foot creek crossing or a step through some puddles.

[Bowen D]

I did get them wet (crossing one creek with shoes on, and in the rain), and I thought they felt just about as great wet as dry. They didn’t get soggy; I mean they didn’t seem to retain a ton of water — but they also didn’t dry all that quickly. For me, that’s fine, wet shoes are a temporary thing & I’d rather have the toughness of a leather shoe vs just trail runners…

[Kevin Babione]

I’m so glad you liked them!  I’ve never hesitated to get them wet either, but agree that they do take longer to dry than a mesh trail runner.  Danner does offer the 2650 in a mesh version rather than the leather as well.  My daughter has them in mesh and absolutely loves them.

[Terran Terran]

I had a pair for a few weeks. I like Danner products overall. I wear their boots and sandals. The leather thong on the sandals doesn’t last long though. I switched to Tevas . The 2650’s are very comfortable and well built. While they fit well, they didn’t inspire great confidence in me as a technical shoe. A nice looking shoe. As it was, they didn’t hold up to the CMD* test. For me, I found a better fit with a pair of Keen’s. Neither one being good for creek crossings, though vented Keens dry quickly. I’ve settled on Topos for getting wet. I may eventually get another pair of Danners, but mostly just for everyday wear. They’re a nice shoe.

* Colorado Mountain Dog

[Bowen D]

Wow I had no idea they came in so many variations!

[Author]

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