When we have good posture, the muscles surrounding the spine are balanced and supporting the body equally. Good posture helps keep bones and joints in the correct position to prevent any muscle imbalances and decrease injury rate as well as decrease the wear and tear on your joints. Good posture also helps make for a healthy spine which regulates our body's sensory and autonomic functions. on the contrary, bad posture can decrease your lung capacity and compress your lungs making it more difficult to breathe. Poor posture can cause tension headaches, due to increased muscle tension in the back of the neck. Often if we correct our posture, we can reduce muscle tension and improve our headaches.

Having good posture can improve your confidence mood and overall health. Researchers at several top academic institutions, including Harvard, have been studying the link between bad posture and the brain and their recent findings show that improving posture can improve the brain’s function, and thus your mood and memory levels. Researchers found when standing in a confident, tall stance, your decision-making is subconsciously affected. 

When your bones and joints are in the correct alignment with one another, it allows the muscles to relax and do what they are intended to do so that you'll have more energy and less fatigue. It's basically because the muscles don't have to work as hard on normal daily tasks and to do what they are supposed to do.