That's the question I'm trying to find an answer for. I've been running in Nike Free running shoes ever since my first run in early 2007. The Free's are special, the sole is divided into small segments to increase flexibility to a maximum. If you're used to wearing "standard" running shoes, that particular model will certainly surprise you the first time you wear them - it's probably unlike anything you've worn before when it comes to running equipment or even shoes in general. It's almost like you're not wearing any - almost. Switching from a normal running shoe to the Free is like taking off concrete blocks, it was an eye-opening experience for me.
Lots of different opinions are floating around when it comes to Nike's unusual offering. "It doesn't even come close to running barefoot", they say. "It's only for training, 5-10k runs". "You can't run a marathon in it without injury". "It can't be your primary running shoe", some proclaim. Nike doesn't help by labeling the shoe a training instrument, not a regular running shoe. Whatever your opinion might be, fact is that the shoe can be your one and only running shoe, I know from experience. Up until February 2009, I had not worn anything else. In January, I ran the Dubai marathon in them. Shoe-wise, it was a pleasant experience. No issues whatsoever. None! So, you can indeed run a marathon in Nike Free's. The critical thing is though that you need to get used to the Free experience before doing so. Slowly increase distances to make sure that your feet can catch up without injury. As long as you keep that in mind, the Free works for just about anything...
Right after Dubai, I thought about replacing my worn-out Free 5.0 V3 with a new pair. That's when I stumbled across the Adidas Adizero line of running shoes. These are similar to the Free in that they represent a minimalist design. The sole, however, is more traditional and not as flexible as the Free's. On my first run, the Adidas Adizero Adios felt great. Running fast seemed to require considerably less effort. Several runs later, I still felt that fast paces were easier to handle in my new shoe of choice. I must say that it took quite some time until I felt truly comfortable in the Adizero Adios during long runs. Now, more than 600k and a marathon later, the Adios feels as good during runs and races as the Free.
The Adidas Adizero Adios still seems to be better suited for higher paces than the Nike Free I had which is why I'm going to keep the Adios for now. It's all subjective of course. Maybe a lighter version of the Free might feel the same. I tried the 3.0 back in 2007 and switched back due to knee problems - maybe it was just too early, the results might be different now. In any case, it's good to know that Nike is not the only one to offer lightweight running shoes. For those of you who're looking for alternatives, the Adidas Adizero Adios might be the perfect choice.
What's your take on the Free? Can the Adizero match up?