Musical rhythms are based on patterns between sounds and silences, notes and pauses, allegros and adagios. In yoga, we can move to music to help get into the groove. Music is fun to move to for this reason - we can let the rhythm carry us away. There is no question music aids practice on those days when we're overtired or weary. But without music, we're forced to 'move within'. We're forced to go within one's being, beneath the skin, and it's discipline that spills into every aspect of life. To develop rhythm in yoga means going within, observing the natural rhythms and patterns between our thoughts and feelings, our feelings and willpower, our willpower and thoughts.
The larger rhythm of our daily practice is also cultivated from within, listening to our body's calls and needs and noticing our mental demands and pressures. Sometimes the body and mind are truly aligned, sometimes there is a tug-of-war, but observing what goes on within determines a frequency to our movement -- a frequency and tempo between stillness and exercise we can actively cultivate. What also arises in a rhythm in working on asanas that we struggle with and need a bit of tender loving care and those that we already have accomplished.
The dove or kapotasana represents rhythm, a rhythm between upper body and pelvis and legs, and a rhythm between the "holy dimension of the spirit" with the world of visible creation. Physically entering into the final pose, which I'm trying to do here, is alternatively working with the hips and legs and the upper body, the upper body and the pelvis. Once the tension in the legs start to dissolve, I shift to the spine. Once the spine elongates, I shift attention back to the lower half of the body and so on. The rhythm itself softens the body like sand.