2019 was the first full year the Nike Vaporfly became widely available to the public. The year of the Vaporfly. The proliferation of new records and fast times set by runners wearing Vaporflys make it clear that the Vaporfly helps most runners run faster. Will 2020 bring us a Trail Version of the Vaporfly?
There are several theories as to why Vaporflys make running easier:
- A high stack height increases stride length by increasing effective length of lower leg.
- A lightweight resilient midsole foam helps in energy return.
- A stiff carbon plate acts like a spring also improving energy return.
- The layering of foam with a stiff plate reduces the vibration that causes fatigue.
Exactly why the Vaporflys work so well is up to conjecture. Any and all the aforementioned theories may be contributory. There have been shoes in the past that had stiff plates that were unremarkable. And there have been shoes with high stack height that offered no speed advantage. If you can believe a recent study that compared the performance of dozens of different shoes, a popular thick soled shoe the Hoka Bondi was actually the slowest of all shoes tested. Of course the Vaporfly was the fastest. Interesting that the slowest, the Bondi, and the fastest, the Vaporfly, have a similar high stack height.
As I have stated before, I think Nike stumbled upon a great combination of resilient foam and a stiff plate. Somehow it just works.
Will 2020 see the Vaporfly technology banned as the Puma brush shoe was banned back in the late 1960’s? Or will 2020 see a trail version of the Vaporfly? A Nike Vaporfly Trail% if you will?
The existing Vaporfly already has a carbon plate that protects a runner’s foot from sharp rocks – a nice feature for a trail running shoe. Unfortunately, the current Vaporfly Next% does not have a grippy outsole required for wet or slippery trail conditions. It also is a bit unstable with a high stack height and narrow foot print. A recipe for ankle twisting. For smooth dry trials without any sharp turns, the existing Vaporfly would be OK. Any courses with uneven terrain would require one to wear ankle braces to avoid rolling and ankle.
So what would a trail version of the Vaporfly look like?
Imagine this. Take the existing Next% and leave the upper unchanged but add a full length grippy cleated rubber outsole. Lower the stack height a bit without losing much of the magic cushioning and widen the footprint for stability. It wouldn’t take much to create a supper fast comfy trail version of the Vaporfly. It is already light, fast and protective with the full length carbon plate. It just needs some enhancement to traction and stability.
Experience Running some Rocky Trails in Vaporfly 4%
Recently I tried running in a pair of the Vaporfly 4% out in the rocky desert. Given my concerns about twisting an ankle in them, I used them with ankle braces. The combination worked pretty well, but is not recommended.
The stiff carbon plate offered terrific protection from all the sharp volcanic rocks on the trail. But that stiffness made them feel a bit clunky as the shoe gets torqued and pushed around by any irregularities on the trail.
The ZoomX (Pebax) foam midsole make the shoe light and cushy, but it also makes them very fragile. You may want to think twice before taking a pair of Vaporflys out on a rocky trail. The ZoomX foam is prone to tearing from encounters with sharp rocks on the trail. Depending upon just how rocky a trail is and how sharp the rocks are, trail running could quickly ruin what is an expensive pair of running shoes.