The mechanics of work

[Cannae]

Hello to all,

 

 

I have a (few) specific questions. From a physiological standpoint, how much work is obtainable with pure muscle power? Also, how is energy used in the body to perform work?

 

Thanks for any help.

[esbo]

depends how much work you use and energy you put in.

[Cannae]

depends how much work you use and energy you put in.

 

Ok but I was asking what is the maximum energy a person can put into work based on physiology.

 

 

 

[Xittenn]

The following is to the best of my limited knowledge!

 

Skeletal muscle works in antagonistic pairs. Skeletal muscle attaches at origins and insertions via tendons, and when a muscle contracts the skeleton will move. Skeletal muscle doesn't relax it has to be stretched back out by the contracted muscles antagonistic pair. When you lift something against gravity the weight acts similarly to the antagonistic skeletal muscle, in that cells that contract are stretched back out as the object attempts to fall back to where it came from. Internally to the body there is a concerto trying to move the skeleton by means of many cells contracting and being stretched back out again. The reason that cells do not maintain their contracted state is that ATP, the unit of biological energy, has a defined value and once it's used more is needed to continue the process. Furthermore the mechanical structure responsible for the contraction must be fed more ATP to be stretched back out or the filaments involved tear. A lack of ATP induces rigor mortis, which is a contraction that is unable to release do to lack of ATP.

 

Here's a video demonstrating the the basic concept.

 

There is also need to account for all other energy input such as the action potential, as well as loses due to internal resistances such as moving the weight of the bone.

Edited May 20, 2012 by Xittenn

[sammy7]

good answer good answer, just some random spewing i guess--- apparantly the body produces like its own body weight in atp each day....amazing imo...also before atp we have NADH or NAD (even coq10 comes after this i think, i think nad is also considered like coenzyme 1 so..) this of course is all going on in the electrontransport chain/oxidative phosphoralation etc etc...so you want to increase atp?? well NADH is something like NIACIN adenine dinucleotide....NIACIN=b3...so thats an important part of the molecule precursor to atp...also one of the first steps in the krebs cycle is acetyl coa-----what is part of this? vitamin b5 pantothenic acid... so a bunch of molecules in krebs cycle and everything after it are composed of/dependent on the b vitamins (water soluble vitamins)....so yeah.........also i think the largest molecule known to man is "titin" something like 34k amino acids or something...and the longest word in the world too depending on how its classified i think (lmao) hahaha yeah....oh yeah and thats a "molecular spring" which does something with muscles.......random musings thanks for your time etc etc lol

Edited May 20, 2012 by sammy7

[Joatmon]

Oxygen consumption is an indicator of aerobic power developed by an athlete. The link gives more details.

 

http://www.topendspo...ests/VO2max.htm

Edited May 20, 2012 by Joatmon