Vata embodies the energy of movement (the air element). It governs all movement—the flow of the breath, the pulsation of the heart, all muscle contractions, tissue movements, cellular mobility—and communication throughout the mind and the nervous system.
Pitta represents the energy of transformation (the fire element). But in living organisms, pitta is largely liquid, which is why water is its secondary element. Pitta is closely related to intelligence, understanding, and the digestion of foods, thoughts, emotions, and experiences; it governs nutrition and metabolism, body temperature, and the light of understanding.
Kapha lends structure, solidity, and cohesiveness to all things. And is therefore associated primarily with the earth and water elements. It also embodies the watery energies of love and compassion. This dosha hydrates all cells and systems lubricates the joints, moisturizes the skin, maintains immunity, and protects the tissues.