Hi, Ruedi, and congratulations on completing the Dovadola-Assisi-Rome Camino. Well done
Although I have been hired to gear test a lot of different brands and models of footwear, Saucony is not one of the companies I've worked for. I can off some insights that might be of help to you based on some research I've briefly done on the ISO.
There are specific technical issues and performance parameters that I look for in a manufacturer's descriptions to help me understand what a
likely performance envelop might be. Keep in mind, though, that while the tech specs are informative, I can not confirm them by having worn the shoes.
First, some basic assumptions about you and your feet and shoes.
- You made no specific mention of pronation or supination or other motion control problems.
- You stated that your ankles are well conditioned, and that you feel they do not present any issues.
- Your feet responded well to using the ISO over varied terrain, including hard surfaces and asphalt, and you were happy with the shoe itself.
- You made mention of rough trails or trail debris. You indicate that there was no real problem with this, which to me means that there was no significant imprinting of that debris and roughness through the sole of the shoe, thus causing pain to your feet.
- Your said your feet "felt it" when carrying a loaded backpack.
- You did not mention your weight, which is a factor for a trail runner's usability for backpacking.
The primary characteristics of concern for the Saucony Peregrine ISO
- Is a neutral shoe that offers no motion control construction.
- It is specifically designed for off road use; it is not a street running shoe
- Setting aside the fancy marketing names Saucony calls its cushioning, the various cushioning formulations and use seems appropriate for a trail runner shoe.
- Saucony does not specify backpacking as a use for the ISO. That's not a big deal in and of itself as an indicator of performance for backpacking. What is important is if the construction, materials, and cushioning is sufficient to support the additional weight of a backpack while walking.
- In some quick research for subjective feedback from backpackers (carrying backpacks) who used the ISO, there was a large percentage of agreement that the shoe was excellent for that purpose.
- There was no feedback found about backpacking on asphalt using the ISO. Nor was there much feedback about the ISO's performance for running only on asphalt-hard surfaces.
Another important factor for you, is that you
already know that you like the ISO and that the ISO like you
You know they fit well and that they are comfortable. Here are my thoughts, some of which have already been suggested in posts above.
1. Double check the fit of the shoe when you are wearing a backpack loaded with the expected weight you might be carrying, then add another 2 to 3 kg additional weight. When extra weight is added by wearing a backpack, that additional weight will put more downward pressure on your feet which may cause them to slightly lengthen and spread out wider.
If you need some tips on shoe fitting in order to make sure your current shoes fit properly you can find my
guidelines in this Thread. Keep in mind, that IF you decide to purchase an additional insole insert for wearing while on asphalt as you have stated, it is best to do the fitting check while the new insert is being worn in the shoe.
2. If you decide that you want extra reinforcement against trail debris and rocks imprinting on your foot, a stiffer outer sole is not necessary to do the job; a cushioned insole (mentioned below) may be sufficient.
If you still find that you want even
more shielding, then you can make a Rock Plate at home. The Rock Plate will slip under your insole and provide a very effective level of protection with out a huge penalty to the 'feel' of the shoe..
Take a thin and flexible plastic, like that found in milk jugs, or a
thin plastic cutting board
View attachment 59537
Using your insole as a template, mark an outline of the insole onto the plastic. Cut out the outline. Place the cut out into the shoe, under your insole. If needed, use some double surface tape, like carpet tape, to affix your new 'rock plates' to the bottom of the shoes.
3. Gel inserts are one type of cushioning insole that some folks find effective. There are also insoles with effective open cell foams and elastic polymers which also are excellent for cushioning. The extra cushioning will also provide additional support to your foot structures. As the foot slightly sinks into the cushion, it creates an impression that will slightly fill in the void under your arches.
This is an example of this type of insert; there are others that can also be effective.
4. I take an extra insole with me, not an extra pair of footwear. I find that if my footwear feels good walking, it will be sufficiently comfortable for lounging around after a long day of backpacking or walking Camino. Of course, wearing lightweight trail runners rather than heavier footwear make this option easy.
I designate one insole as my walking insole. That's the one I will. . well. . do all my backpacking and Camino walking with. The
extra insole is usually the one that came with the shoe, since I always replace the factory insole with a third party insole.
The factory insoles are usually very light. When I swap out insoles at the end of the day, and will be walking around the village or town seeing the sights, getting dinner, shopping, etc, the factory insoles are more than sufficient for that walking task. Swapping out insoles allows my walking insoles to air out.
5. There is an excellent chance that with a good, third party CUSHIONING insole, that you will be fine with a backpack while walking on asphalt-hard surfaces.
Should there be any questions or issue that you think I can be of help with, feel free to send me a PM.