By the year 5555, two important questions will have been resolved for humanity:
1) the conflict between leisure and exercise will be decided in favour of leisure, as we substitute cute little mechanised karts (or possibly some form of un-armoured personnel carriers) for legs. Apparently, they will also feature Dr Octopus-like arms, too, as we will apparently not use any of our limbs.
2) natural evolution will finally lose its race with technologically-assisted evolution.
Of these, the first forecast seems less likely, unless teledildonics has also made incredible advances (not impossible in 2500 years, I guess…)