KEY POINTS:
Imagine an office chair which clings to every subtle contour of your backside.
That dream of sitting down for even longer periods of time just took a step closer to reality with a new aid: virtual buttocks.
Auckland University masters student Sarah Cox, 22, spent most of last year creating the most detailed and complex computer representation of the human buttocks to date.
The three-dimensional model incorporates 42 muscles and the pelvis and leg bones.
This is cutting edge research into putting bums on seats - the virtual model of the male buttocks demonstrates what happens to muscles on sitting, allowing furniture designers to create better chairs.
"It's a strange topic but so many people will sit for eight hours or so a day in an office chair that it's actually really important to be sitting on something that's comfortable."
While a lot is known about seats, not much is known about where pressure is exerted in the muscles, and how they change their shape in a seated position.
"We hope it will provide valuable information about how chair design can be altered to relieve pressure in the legs and buttocks."
It is also possible the research could help prevent pressure sores for people in wheelchairs.
To design the model, Miss Cox started with data from a male cadaver in the US National Library of Medicine's Visible Human Project.
Bodies donated to the project were sectioned at 1mm intervals (male) and one-third of a millimetre (female) and photographed, enabling medical researchers to have a complete digital image library of the male and female body. Images and measurements from the cadaver were used to create a model of the buttocks.
The data was then combined with existing hamstring and quadriceps (the muscles of the front of the thigh) models developed at the university's Bioengineering Institute, known worldwide for its computational modelling of human physiology.
Miss Cox said the next step involves measuring the pressure exerted by different sections of the buttocks on a chair.
She said the male model would give a general idea as to what would happen when people sat.
A female buttocks model is on the way, as are more buttocks of different shapes and sizes.
"It's just very time consuming creating the models - it will eventually be done," Miss Cox said.
Her research will be used by Formway, an office furniture company which approached the university for scientific input into chair design.
