Now that many new cars are coming with have high-def wide-angle rear view cameras, I don't really need my neck muscles anymore. At some point we'll "evolve" to rocks... rocks with wifi.
That reminds me of a TED talk I saw where the speaker was saying that something he's noticed with a lot of academics and tech types is that they only care about flexing their mental muscles; their bodies are only useful for moving their brain from one place to another, so a lot of what they build is done to make it so they have to use their bodies less.
I picture something more like floating, life-extension vats where people spend their whole lives, getting entertainment, VR images, and drugs piped into their brains. Robots will do everything else.
Living involves the acts of experiencing the real world and doing things for yourself.