[guilloche]

It seems that I am not the only one gotten hurt by standing all day long.

In my case, the knees are fine, the joint between my right thigh and body got hurt baddly.

So, do not stand a lot, do not sit all day long either.

Do drink water regularly, (kidney stones for sitting programmers) too much water will cause kidney problems too.

[kennu]

Maybe lying on a couch is the safest choice then. :-)

[innguest]

That's why I've been waiting forever for a certain one-handed chorded keyboard called Twiddler. :) (I'm not affiliated with them).

[blunte]

Everyone has some difference in leg length. Perhaps your leg length difference is great enough that it's putting too much lateral stress on your pelvis/hips.

[collyw]

More likely that he putting more pressure on one than the other without realizing it. We have lots on unconscious habits we are unaware of.