There are many theories about energy. Hippocrates believed that the same vital force of energy flows through all things. He regarded the body as whole complete organism. He did not think of the body as independent parts. His thinking was that if there is a change in one part of an organism then that affects all of the other parts. The interdependence of the organism can applied to all living things. You can then understand how our energy can affect others.
By practicing yoga you up your positive energy which will have a positive effect on all others that you meet. You become more aware of your own energy and the impact it can have on others. Awareness of your own energy helps you to link with others in a more meaningful way.