Movement

Movement and exercise are one of the rights of the body. Just as food, drink, and rest are needed to enable a healthy bod to function, regular motion and exertion are as well. In the past, this did not warrant any special consideration. Our ancestors got significant motion just from the requirements of life. If they worked on farms, digging the earth, harvesting the fields, and taking care of the animals ensured enough physical activity. Otherwise, just walking to fetch the daily water or riding a horse was a workout in itself. But times have changed. Many of us can spend our entire day almost sitting in one place and not walking more than the distance of our home to the car in the garage.

Why do we need exercise? In turns out that several of our body systems simple do much better with it

Gut Health – a 2014 study from Ireland's University College Cork showed the greatest diversity of gut bacteria in athletes
Joint Nutrition – unlike our muscles and organs which have blood vessels to bring them nutrients and remove wastes, cartilage only this need fulfilled through the compression and traction of our joints by causing the movement of synovial fluid
Positive Emotions - a 2000 study from Duke University showed that exercise is better than Zoloft at treating depression
Improved Brain Function – an aggressive physical education program in the Naperville school district in Illinois has resulted them in achieving the highest science test scores in the world

Sources: Spark: The Revolutionary New Science of Exercise and the the Brain, John J. Ratey, MD; Brain Maker, David Perlmutter, MD.