When I talk about my teachers having so much energy from taiji, it has to do a lot with the fact that they save energy more than actually producing it out of nowhere, which seems impossible to the average person. This is one thing every practitioner who practices long enough learns about taijiquan. It’s true, you get only so much Qi (energy) when you’re born and as life progresses you lose it, or at least, lose access to it. But you can get it back, and one stepping stone to do that is by learning to conserve it, not waste it, use the energy you have wisely, and consciously bringing stuck qi back into availability. By doing taiji movement, you clear out superfluous energy, which in turn attracts your original qi and rebuilds it. It’s fantastic to reunite with what is essentially a part of ourselves.