Winter is ruled by the water element: the most nourishing and essential substance for life and the most Yin of all the elements. This element stores much of people's reserves of energy. That's why rest is crucial in the winter. This time of year, over-work and lack of sleep easily depletes the water element and the kidneys, especially. So our Winter practices help us reenergise and rebalance our water element through yoga postures stimulating the water meridians and energy points in our bodies.