Internal martial art, like tai chi, is about physical fitness. On the other hand, meditation, like Zen and Taoist meditation, is about mental healing. They are both internal arts. The question is: where do they meet?
To answer this question, we must first identify which part of our body can be both responsible for physical fitness and mental healing.
To answer the above identification question, we have to look at a practice that can be used both for physical fitness and mental healing. And then we have to answer why it can achieved the results of both physical fitness and mental healing.
The practice is the now rather popular zhan zhuang - standing meditation.
Empirically, the good benefits of zhan zhuang for both physical fitness and mental healing have been reaped by countless practitioners around the world, quite naturally mostly in the East with increasing number in the West. Decades ago, motivational speaker Tony Robbins said in his unlimited power seminar (I paraphrase): "you don't need to understand everything about the internal wiring to get the benefit of electricity. Your only need to know how to switch on the light!" True, and more true for zhan zhuang. Reading my explanations doesn't mean you can get the benefits out of zhan zhuang, while practitioners who don't know anything about its internal logic can still get good benefits, well, with the help of a good teacher! What I am also saying is that "you still have to practise after understanding!"
The gist of the matter is, if a practitioner can activate a certain group of muscles he can deliver both physical fitness and mental healing benefits. Such connection, in physiological terminology are muscles being connected/excited by their connecting fascia. And in chi kung's terminology, a practitioner can fill chi in that particular muscles group during mindful breathing. I mean chi-sensation (得氣感).
Where is the fascia/muscle group? In zhan zhuang, it starts with our big toes, running up through our inner thigh, via our pelvic floor muscles, Dan Tien, diaphragm, passing through our heart's fascia and up to our throat and tongue.
Readers who have some experience in internal martial art (such as tai chi) can perhaps understand why their teachers asked them to use their toes to grasp the floor (actually it should primarily be their "big toes") and to touch their pallet with their tongues (actually it should be "to energize your throat and tongue"). And readers who have some meditative experience can perhaps understand why their teachers ask them to visualize "a loving or passionate heart". Those who are familiar with Taoist meditation, may perhaps recall the requirement of "breathing from your ankles" (呼吸以踵) (seated meditation is from ankles rather than big toes).
If you still don't understand what I am talking about, not to worry, just follow your teacher's advice, practise, and you can get the good benefits. On the other hand, if you smile, perhaps you have experientially understood what I am talking about, then I find a kindred soul. Most others, assuming that they are interested in the subject matter, need more time to explore.