system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel] How is Tony Stark able to fly without hurting his neck? He flies parallel to the ground but with his head facing forward, and I imagine it would be extremely uncomfortable long-term.

Just try laying flat on your stomach but still facing forward towards the wall in front of you, it's uncomfortable. If he was flying for long periods of time I imagine it would seriously put a crick in his neck.
gpt
Tony Stark most likely takes muscle relaxers for his neck and other muscles that would tense up from being immobile for long periods of time. On top of that he now has a stabilized form of extremis constantly healing him.