Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

It seems to me that my forearm is naturally in a more pronated position than the anatomic (supinated) position and that it actually takes work to make it hold the supinated position. Anyone an expert in human anatomy/physiology here or know of any sources that could point towards a more scientific answer?

share|improve this question

The main reason why the anatomic position is supinated is because the radius and ulna are crossed when the arm is pronated and parallel when the arm is supinated. It doesn't have anything to do with the resting state of the arm, it's just the easiest way to arrange the bones neatly for description and analysis.

Arm pronated and supinated

share|improve this answer
I agree with the above answer. Also, we all tend to use our forearm more in the pronated form (holding, hand shake, driving, etc) so I guess it becomes second nature to us. – John Sep 2 '13 at 11:36

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.