I practiced the traditional style of hsingi (Sun Lu Tang – Chang Chuen-feng) for about four years (going to class twice a week) in which every posture felt like an isometric exercise. I have to admit, it got you in shape. I never felt stronger and this was without weight lifting. It was hard to practice softly, though, since my body was not “fit” enough. Only after many, many years of practice can one reach the level of softness and relaxation to generate qi.
I haven’t practiced the softer styles of hsingi. Maybe it’s different.
We also practiced San Ti (posture two with extended palm upright) and zhan zhuang which I think are fasters way of generating and circulating qi.
However, after many years of practicing taiji, I’ve begun to learn Wild Goose qigong and find it vastly superior in generating and eventually circulating qi in a shorter period of time. It’s not only the forms, but everything is done very softly.
At this stage, I’m more interested in generating qi for health, not martial arts.