The Ultimate Active Survivalist: The Cyberman
The previous post showed a natural human form however if we are to avoid complete bodily breakdown and death it will be inevitable that parts will need to be replaced. It is already happening now with replacement joints being quite common. Obviously it would be best to avoid getting replacement bits for as long as possible but when the time comes to do a bit of modification I say embrace it.
The Cybermen replaced almost all parts of their bodies except parts of their brain although some say that even this was totally replaced t00 - probably a good idea.
Here is a link to a website that has details on all the different Cybermen models and more.
Cybermen were constantly adjusting and improving their design. This is what makes them the ultimate Active Survivalists!