Stretching

During the week, I usually train every morning before going to work for about 1 hour. I start with general warm-up for about 30 - 40 min with including stretching exercises, then basic kata sanchin and basics, again some stretching, then some advanced techniques (either weapon or advanced kata) then tensho.
As explained before, sanchin is for me also a chi cultivation exercise (I study goju ryu karate).
What I notice is that after training sanchin
when stretching, the muscles are more relaxed and warmed-up and stretching is a lot 'deeper' and intense.
Are there others who have simular experiences ? Is qi-qong (chi-qong) not an art in that area ?

FWIW, I stretch before I do any training so that I warm up the joints of my body.
My body always feels bette when I am training if I have properly warmed up first.

Even if I am just doing some mild Qigong work then I will sretch and warm up my joints.