"The ultimate test of a scientific hypothesis is experiment. Experiment specifically means that you don't just wait for nature to do something, and passively observe it and see what it correlates with. You go in there and do something. You manipulate. You change something, in a systematic way, and compare the result with a 'control' that lacks the change, or you compare it with a different change."
- Richard Dawkins, The Greatest Show on Earth: The Evidence for Evolution, p.66
One way to view your practice of mind-body arts is that you are conducting an experiment with your body-mind. How does the practice of Tai Chi, Qigong, Yoga, or walking change you, change your attitude, change your mood, change your body, change your feelings.
Keep a log, a journal, a record of your progress. Be exacting, precise, factual in your reporting. Be scientific.
Quantify your key measurements. Consistently measure and record your blood pressure, hours of sleep, caloric intake, hours of exercise, etc. Use some psychological rating scale. Measure range of motion and flexibility. Quantify and compare changes over time.
Change something! Learn a new Taijiquan form, and articulate what happens. Change the pace of a form you know well.
Be systematic. Don't quit. Persist. Compare.
It is time for you to evolve, modify, change, become!!