Progression from Bridge Curls to Single Leg Bridge Curls

Totally agree that the forum/video feedback will give additional information and is extremely valuable. At the same time I find it annoying if e.g. the follow along or demo videos don't live up to the requirements put forth on the forum, which not always are consistent between the coaches, either. In the end of course, we only are accountable to ourselves and it's up to everyone to decide how far they want to go down that rabbit hole. 

I can't imagine anyone meaning that you should keep PPT in the bridge. That just won't work, as you recognized. However, definitely keep your glutes engaged and don't just dump into the lower back for the arch, try to involve the thoracic spine as much as possible (see FL iM progressions)

"...using nothing other than hamstring and pushing hips up with ppt and straight body at 4x10r as mastery."

That part in this thread got me confused, as nobody objected to "ppt and straight body." 
Thanks for clarifying @Kai Ewert Thoracic extension is a major weakness of mine though. working on it. 
 

On 12/6/2016 at 1:33 PM, Kai Ewert said:

I can't imagine anyone meaning that you should keep PPT in the bridge. That just won't work, as you recognized. However, definitely keep your glutes engaged and don't just dump into the lower back for the arch, try to involve the thoracic spine as much as possible (see FL iM progressions)

In full thoracic bridge holding a neutral pelvic tilt, as best as we can, will prevent a number of lower back problems associated with holding full bridge in general. 

In yoga there is a position called, in English, "Fish" that aims to open the thoracic spine through the rib cage and forces one to hold a neutral pelvic tilt. 

I just did this cool "experiment" with my roller-skates. Please, ignore my technique. It's really ugly right now. But… this was the first time I was able to do a single leg curl. Yay….  maybe this is a good temporary solution for you too, @Jin Liu   

Haha, nice @Suzanna McGee! This is what i meant by a "very slippery slider" in my post, lol. But I don't have roller skaters and my best option right now is wearing socks on the wood floor. I'm getting more and more holes in the socks...

9 minutes ago, Jin Liu said:

Haha, nice @Suzanna McGee! This is what i meant by a "very slippery slider" in my post, lol. But I don't have roller skaters and my best option right now is wearing socks on the wood floor. I'm getting more and more holes in the socks...

Jin, when I did the first set, it felt so slippery, that I couldn't control it at all (compared to the furniture slider that I was using before). And you know what? Today, I am so SORE in my calves that I would not believe it. Deep inside in my calves, those stabilizing muscles when I just stand around… hamstrings are pretty ok. I guess I have many deficiencies in the back of those legs   

Interesting, I'd have never thought that'd kill the calves.. but i guess you do need extra strength to control and smooth out the momentum from the roller skaters. This IM has really opened my eyes. I've never experienced huge hamstring cramp like this before.