Brooks DNA

After seeing the Brooks Cavalcade of Curiosities last year, I have always kind of envied the person who got to be the Jesus Lizard. And, the other day when I was sitting very still for a very long time collecting data, I started thinking about how nice it would be to just get up and run across a pool of non-Newtonian liquid. Being that I couldn't (or I would screw up the data I had already patiently collected), I decided to write a blog post about it at lunch.

Brooks' cushioning system is known as Brooks DNA and is "engineered from what's called a non-Newtonian liquid". Non-Newtonian fluids have a non-linear shear stress vs. shear rate response (for the engineers who read this blog). More simply put, if you apply a sudden, quick force, the non-Newtonian substance behaves like a solid... if you apply the force more gradually, the non-Newtonian substance behaves more like a fluid. So, what does this mean for your sneaker? A lot of people initially describe Brook's cushioning system as being "pillowey" when they're just standing or easy jogging (i.e., applying force more gradually). However, when they start "really running", the shoe seems to firm up a bit (i.e., applying a greater force more suddenly). In other words, the cushioning is adaptive, or as they say - "soft comfort when you want it, firm support when you need it".

... and I finally remember where I originally heard this term: Bio-Fluids class (blood is also a non-Newtonian fluid)!