I have no idea Kungfu and yoga has so much in common! Look at this warrior I pose. It's exactly the same stance as Gongbu! Back foot firm on the floor at 45 to 60 degrees. Back knee straight. Pelvis and body square to the front. Front thigh parallel to the floor. The only difference are the hands, arms and neck.
Gongbu/Warrior I is a wonderful stance and possibly the hardest to do correctly. It strengthens and stretches various parts of hips, legs and ankles. It also opens up the pelvis and chest. With hand-legs-arms coordination, it's also an introduction to self awareness.
For the longest time, I could never make my back knee straight. I thought it was impossible. It turned out I simply didn't tighten the right muscles (specifically my hamstring and butt.) Only when my back knee is straight, I was able to turn my hips and body fully forward.
Now I just have to focus on stepping into the correct Gongbu all the time!
PS. This site tells an interesting bit of why seemingly peaceful yogis named their poses warriors.
