Physics of contortion

[cookbeat01]

I am trying to apply the laws of physics to contortion acts (backbend, splits, etc.) However, I do nkt know what laws of physics apply to the contortionist's flexibility. Could someone please help me out? Also, I mean physics when I say it so I do not a reply saying this should do with biology.

[J.C.MacSwell]

A contortionist's modulus of elasticity while relaxed would be much lower than mine and their strain to failure much higher.

 

Basically mechanics and to some extent dynamics. Modelling with ideal elements would give a reasonable first approximation.

[ecoli]

Yes a hydromodularelastic chess set uses the physics of bio-mechanical matter.

p.s. chess and cheese are parallel universes.

 

What-cha talking about?

 

 

As to the original post... A contortionist obey's all the laws of physics, it is imposiible not to... (unless God is a contortionist...lol)

 

A contortionist trains their body for peak flexibility, there muscles can stretch in such ways that normal people can't do... because of restrictions in genes, but mostly due to lack of training.

 

But I supposed it would be interesting to see the difference between a contortionist and a normal persons flexability... I'm sure there are some other properties you could test.

 

I wonder how far it's possible for a contortionist to bend? There has to be some sort of physical limit...

[Mokele]

Basically, this is my field, biomechanics, the application of physics and engineering to figure out how animals move, eat, etc.

 

For contortionists, they basically stretch a lot while young, and thus wind up with very elastic ligaments and tendons. The absolute limit to their abilities is mostly in terms of just how far the joints will allow movement and the limits of stretching muscle and tendons.

 

Mokele

[Rebiu]

I am trying to apply the laws of physics to contortion acts (backbend, splits, etc.) However, I do nkt know what laws of physics apply to the contortionist's flexibility. Could someone please help me out? Also, I mean physics when I say it so I do not a reply saying this should do with biology.

The physics of contortion are pretty basic. I think what you need to understand is the nature of human body.

 

Every joint has a range of motion. Throughout that range of motion the muscles that move and stabilize the joint have a degree of strength that varies with the position of the joint. Because most people do not regularly train these muscles at the extreme range of motion the muscles are weak at these extension and unable to protect the joint from overextension and damage so they contract before that danger zone is reached.

 

Stretching is actual a dynamic overload on the muscle that will strengthen it at the extreme extension thus allowing the muscle to relax farther and farther into the extension. The greater the range of motion the less mechanical leverage is available to prevent overextension and therefore the greater the strength needed to protect the joint so that not only must the muscle increase its strength in these new ranges of motion it must increase its strength to ever increasing levels. Thus stretching to increase flexibility is a strength building exercise.

 

Increasing strength involves body wide changes in physiology brought about by the training effect. To induce these changes significant amount of muscle must be stressed. If a person only does a few static stresses they are unlikely to produce these changes. The most reliable and consistent way to build flexibility is therefore as a part of a strength building regiment. The most reliable way to produce the training effect is to train the larges muscles in the body legs, gluts, and lower back.

 

The joints have a absolute potential range that is independent of the strength limitations of the individual. The hinge joints of the knees and elbows do not have the potential for a wide range of flexibility. The ball joint of the hip allows for flexibility in all directions as well as rotation. The shoulder is not actually a rigid joint but a configuration of bone ends that allows movement of the arm as well a movement of the shoulder. The back is a series of joints that allow extreme increases range of motion.