Cushioning is another place where you’re going to see or hear the word minimalist. I’m going to stick with high cushion and low cushioned shoes as terms to avoid confusion. Cushioning is usually talked about in millimeters (mm). As we have seen in recent years, there are shoes out there with barely anything under your feet, aka barefoot running shoes, and those with cushioning over an inch thick (an inch is 25.4 mm).
The theories on why one shoe is better for runners abound and often contradict one another. The idea behind high cushion is that it reduces impact forces and thus reduces injury. What does the research say? Research does not support a lower injury risk or less muscle fatigue with a higher cushioned shoe. It is the alignment of our lower leg that changes impact forces, and the alignment of our leg is changed due to sensory input our brain receives as we run.
Don’t fret all is not lost my high cushion loving runners. Here are some things we know about running with and without cushion.
Heel striking runners should not run in low cushioned shoes. It can be hard to tell if you are a heel, midfoot, or forefoot striker. The most reliable way is to look at the bottom of your shoe or have someone watch you run (when you’re not paying attention to your foot strike, because you’ll alter it). If you have more wear on the heel of your shoe, you’re a heel striker. About 80% of runners are, it’s not a bad thing, so long as you wear the right shoes. If the wear on the sole of your shoe is on the forefoot, you’re a forefoot striker. This is pretty rare and is usually sprinters and shorter distance runners.
Higher cushioned shoes can cause instability in the ankles and hips, especially, for beginning runners who have not developed the ankle and core strength to tolerate the instability. This instability can also be a problem on trails, which are already uneven. Some high cushioned shoes compensate by having a wider sole, although, this solves SOME of the instability it adds the problem of a wide ass shoe. A wider sole can get stuck between rocks easier. Also keep in mind that a wide ass shoe sole does not always translate into a wider toe box.
High cushioned shoes can protect the bottom of your feet from rocks, roots, and other nasties. As we age we lose some of the natural cushioning on the bottom of our feet making a higher cushioned shoe possibly a better option for runners as they age.
Heavier runners (over 170 for men and over 160 for women) are going to want a shoe with stiffer cushioning rather than the pillow soft stuff because of the compression that occurs when you land. If you have super soft cushion, it’s not providing you with much protection.
What I want you to take away from this whole series on shoes is everyone is an individual and research results are an average. Sometimes if researchers look at individual runners there is a difference. It could just be the runner’s belief (placebo effect) or other biomechanical differences between runners, but if it makes a difference for you, stick with the shoes or dump them as appropriate.
Wear what makes you happy and don’t be afraid to dry new stuff.