on Sunday, April 3, 2011



The inefficiency of the spring floors and in the vault spring boards was never really something I considered.    This was a topic brought up in a section of an article called Jump and Jive which I found quite interesting.  Interesting results were obtained from an experiment performed examining high quality videos of gymnasts jumping.

What they found was that they gymnast would do an extra down and up when jumping on the flooe or springboards.  They took high-speed footage  discovered that this inefficiency was actually do to the floor itself.  The problem lies in the floor/springboard essentially being "out of tune".  They compared this to a diving board, because you can move the fulcrum on he board to make it behave how you want it to so that you get the correct rhythm and you fall on the board when the board is still going down.  If you were to jump on it when it's going up energy is wasted.  So the problem with the floor and springboards is that the gymnast is wasting energy by jumping on the apparatus that is not in tune.
http://www.aboutballet.com/vaulting-boards-c-594.html
The video of this wasn't able to be directly linked but it can be found here.

Some solutions for this including lowering the stiffness of the springs, however this causes a new problem of making the gymnasts travel too far on their tumbling passes. It was said that

"Combined spring/foam floors could offer some opportunity for improvement but further research is necessary. Linking the issue to injuries or performance is premature at this point, but Sands knows the current situation is not optimal."   

The other downside to the issue is that this is also putting a lot of strain on the  athletes legs because in order to counter the inefficiency they must increase their own strength.  In other words the inefficiency and the extra strain makes for a pretty good recipe for strain related injuries, such as rupturing an Achilles tendon. 

In school it seems like we talk a lot about the efficiency of our designs from an engineering perspective so this is interesting to see how what seems like a very small inefficiency can cause a lot of problems for athletes.  It will definitely be interesting over the next few years to see just what they come up with.