Have you ever given any thought to the relationship between the stiffness of a sport/dance surface and the force reduction level? I realize the most common answer to that question is something like, ‘No, not really’. As a designer and sports surface engineer, I my experience is that relatively small changes in force reduction (say 5%) represent a much larger change in the actual stiffness of the sport/dance surface. The attached paper and spreadsheet will help you understand how the stiffness of the surface is related to the force reduction property.
When I started working in the sports surface market I had several mentors. One of them that made a lasting impression was Jay Seals. Jay and I would sit and talk about sport surface performance, but those talks were not what you’d expect. Jay would relate chaos theory, string theory and even quantum mechanics to sports surface performance, and I’d sit there trying to understand the connection. I am a math nerd at heart and I enjoyed mechanical physics. During last summer I took some time to explore how I could use a very simplified model of a sport surface to explore force reduction levels. The results are the attached paper and spreadsheet files.
You see much of the testing that is done on sport or dance surfaces takes what is a very complicated biomechanical system impacting a very non-linear sport/dance surface, and attempts to quantify the differences the athlete will feel on the surface down to a single number generated from a simple mechanical test. How those results reflect the actual property of the sport or dance surface gets lost, or maybe was never actually considered. This post provides a very general view into the physics involved in determining the force reduction properties of a a sport or dance surface. I’ll warn you this is a bit of a dry read, and it’s certainly not for everyone.
The following contains the article:
For those very interested in this topic, I’ve also provided the spreadsheet used to generate the calculations.