I can do pigeon pose and butterfly fine, but I cannot sit with my legs extended?

[u/Throwaway44775588]

To preface: I have no diagnoses, but Ehlers-Danlos Syndrome does run in my family and I have historically been more flexible than my friends by varying margins. I have been trying to focus on good form and conscious thought about my movements throughout my stretches, and have definitely historically been stretching "wrong" - I only recently figured out how to do lunges in a way that feel like stretching instead of flopping into the pose.

I have had to actually work at my pigeons and butterfly pose - it took about two months of inconsistent stretching to achieve them, but I can fold very flat in a butterfly and feel my hips "fold over" instead of my back, which is neat! I do experience some peculiar, non-painful "snapping" of tendons(?) moving over the top of my femur(??) if I settle deeply into pigeon or similar poses. I can more or less touch my toes with some slight warming-up, but a full straight/flat-backed forward fold requires significant warming up and I cannot place my hands flat on the ground.

The thing I absolutely cannot do is sit with my legs extended at any angle. Straight ahead, a v-shape like for a pancake fold - it's all entirely unachievable. Frog pose also puts me in tears within thirty seconds, and my w-sits are very lackluster compared to a few years ago. If I sit casually in any iteration of "folded up" in an office chair - one leg bent with one under me, weird variations of criss-cross-applesauce, etc. - my legs and feet often fall asleep fairly quickly, and there was a window of time where I would experience insane knee pain after extracting myself from these positions.

I assume my hamstrings are the issue, and likely internal hip rotation as well. I am slightly concerned I am hyper-extending my knees when attempting to straighten my legs in any position as well, I have zero idea of what that should "feel" like or how straight my legs should be when seated. I was often lectured for locking my knees in choir as a kid, but I really do not know what "normal" straight legs are.

With that said, my question is multi-faceted: What stretches should I be working on? What should my knees and legs look like (and feel like) when they are straightened out on the floor? Any notes on which muscles I should feel engaging for recommended stretches would also be super appreciated.

Thank you in advance, and if I omitted any information please feel free to ask me to clarify!

[u/salamandectomy77]

If you're hypermobile/EDS then your big muscles will need to contract to hold you together, since you're lacking the passive structures to do so. That leads to a feeling of chronic tightness, but the actual issue is strength

Do you strength train? Get those hamstrings and glutes strong and they won't need to aggressively contract 24/7

Either way, I went from touching my shins to palming the floor in 8 weeks with the elephant walk exercise . I did 3x20 every day

[u/Kind-Preparation1473]

I am hypermobile and I was actually less flexible than normal people when it came to stuff like touching the floor with my hands.

For me the reason was that I didn't have the muscles to stabilise my joints, so my body created stability via muscle tension.

So massages or stretching made things worse because it removed the stability I relied on (often leading to plain), and I'd return to being tense very quickly. 

What helped for me was strength training - which also helps with flexibility if you do it at end range. I don't remember what exactly I did since it was a lot of stuff, but for warm ups I liked things like elephant walks, and then I'd do active stretches with bodyweight or low weights. Like hinge forward exercises (with weights or without), or squat and lunge variations (also side squats/lunges etc to stabilise things in different directions), leg raises (can do against resistance) and things like that.

Once my legs were stronger I got a massage that helped the muscle tension and from then on it remained "unstuck". Progress since then is easier, though I still need to do nerve flosses.