For the neck, consider that the overall line of action often is closely related to the line of the spine. Not the same as. Just there‘s a relationship between the two. And the spine goes through your neck, and is a LOT less bendy than people might assume. I mean, yes spines are flexible, really flexible. But they‘re not pipe cleaner flexible.
If you‘re not used to watching ballet or figure skating, definitely hit up youtube for some video. Or contortionist stuff like Cirque du Soleil. Yes, there‘s male contortionists. Yes, there‘s male figure skaters and danseurs.
Figure skating and the like will also help with static poses because they have a lot of static poses where you can learn to see the muscle movements it takes to hold still. Yes, holding still takes muscle. Lots of muscle. And there can be a lot of movement involved, and in a gesture drawing we draw what moves. There‘s even movement involved in a relaxed pose like for sleep, but in my opinion those are more advanced.
In the LOA photo set we more usually have ballet poses than figure skating, but the two sports are really similar on the fundamentals, and it‘s easier to learn the figure skating names for moves usually. If you can name it you can search for it ;)
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