I don't have a video or pic, sadly. So I can only describe how it felt and the change.
So, my gelding has a really weak back from never using his hindquarters. Whenever I would ride (really showed up bareback) afterwards, when I got off or untacked, his back would be insanely dipped.
So, I got on him bareback the other day and walked and trotted him. He was in a halter and I tried tipping his nose in towards his chest a little bit while keeping his head level, kept my leg on him to keep a good pace, and felt a huge difference! His trot was alot smoother, his back didnt feel bony, and his withers didnt stab me. Part of me wants to say it felt like riding up hill, but im not sure. When I got off, his back was lifted like I had just done a bunch of back lifts!! (I did a little dance)
Could it be by simply tipping his nose in while keeping his head level and keeping him at a decent pace it got him to engage his hindquarters?
Might, might, be able to get a video tomorrow. Ill try.