Comparing Several Carbon Fiber Racing Shoes

By: Brian Kasten

For a recent hard 20 miler I split the run up into 3 segments to compare different carbon fiber racing shoes to help me determine which ones I liked best. I will attempt to break them down for you in the following article.

But first some details on the shoes:

Vaporfly 4% – Purchased in October 2018 (2.5 years old) with 78 miles on them. This was my 2nd pair.

Vaporfly Next % – Purchased in September 2020 with 0 miles on them.

Endorphin Pro – Purchased in March 2021 with 2 miles on them.

 Heel ForefootDropWeight
4%39 mm29 mm10 mm6.9 oz
Next %40 mm32 mm8 mm6.6 oz
Pro39 mm31 mm8 mm7.5 oz

Here are my stats in the shoes for the 20 miler:

 Miles Time Pace Elev GainElev LossCadence Stride Length
Next %50:31:476:21.44545171.81.474

The first 15 miles of the run were running a fairly flat loop around my neighborhood and the last 5 (in the Pro) included large sections of downhill as I was planning to finish at Antrim.

Thoughts on comparing my splits:

I had never run a 20 miler this fast in my life. I kept wondering to myself when I was going to crash and burn but it never happened. I felt like I could have kept going for several more miles. I naturally had hoped for a negative split on the run but did not think it would happen based on how quickly I went out of the gate. Transitioning from mile 10 – 11 I was still fresh enough that I could clearly feel the difference between the 4% and the Next %. But by the time I put on the Endorphin Pro I figured I would have been spent and naturally faded but it never happened. But the first 2 miles in the Pro were mostly flat and I managed to keep a consistent pace (6:19 + 6:22). The next 2 miles had solid stretches of downhill but the last half mile of mile 20 was flat with a small uphill that led me to hit mile 20 right at the top of the hill at Antrim. I had no problem keeping the 6:15 ish pace I had going on the flat or the small uphill there at the end.

Thoughts on the Shoes:

Vaporfly 4% Flyknit

I wont talk about these as much as I feel like many people have tried them or heard plenty about them. They have a cushy feeling unlike anything you have ever felt before. When you run in them for the first time you almost feel like you are sink every stride but the energy return on the foam and the carbon fiber plate work together to propel you forward. Its unlike anything made before it. It feels like the faster you run the more you get out of it. The shoe is not very stable laterally and its rather narrow in the mid-foot and does not offer much for arch support. I would be worries about hairpin turns and courses that are not on the most perfect of surfaces. The flyknit upper is nice and it stretches a little, which worked for me with a slightly wider foot. Though it can get warm and it will also absorb water and get heavier if it’s wet out.

Vaporfly Next %

Much of this will focus on comparing it to the 4%. It feels stiffer than the 4%, which I thought was a good thing. You don’t quite get the same amount of sinking feeling to it but it does feel even taller (I looked it up and the stack height is a tad taller). It felt narrower to me than the 4% but I think that was due to the upper being a plastic-y canvas and was not as stretchy for my slightly wider foot. So the upper is much thinner and more efficient that the 4% but I also found it to be rather warm and did not think it was very breathable. Despite some initial concerns about the fit within a few strides I could really feel the speed of the shoe. There is no masking it, this is a fast shoe and you know it. Similar to the 4%, it’s a different feel and fit than most traditional shoes but once you get adjusted to it you will love the speed. The shoe offers slightly more lateral support than the 4% but not a ton, again I would be worries about hairpin turns and courses that are not on the most perfect of surfaces.

Endorphin Pro

This shoe looks more like a traditional running shoe and not some space age racing shoe. The stack height is more inline with a normal shoe as well, but it does use the same type of foam and a carbon fiber plate just like the Nike’s do. My first few strides in it felt a little awkward and like I was really heel striking but I quickly adjusted and it felt far more natural on my feet than the other shoes had. The shoe has a natural rocker motion to it that helps you smoothly round right into your next step. Just like the look it felt more natural once I adjusted to it. The upper on it felt more traditional and more breathable compared to the other shoes. I also felt like it had more lateral support as the base of the shoe felt wider throughout offering more lateral support and it did not have as high of a stack height. There was no heel counter or much for rigidity in the heel if you are looking for that. The shoe didn’t scream FAST at me like the Next % did but I could tell by my pace and my energy output it was just as efficient. 

Final Thoughts:

The Vaporfly 4% while being a ground breaking shoe, amazing in its own right and a trend setter were outclassed by both of the other shoes.

The Vaporfly Next % to me would probably be my choice for anything half marathon or less that was on good surfaces without a lot of hairpin turns.

The Endorphin Pro while it doesn’t wow you like the Next % does, I would put it neck and neck with the Next %. I would really consider using it at the marathon distance over the Next % due to the more traditional feel, more support and stability of the shoe. Especially if there was uneven surfaces or lots of sharp turns on the course. Not to mention the shoe is $50 cheaper.

For more information on my run and splits check out my Garmin Data:

Leave a Reply