There is a lovely clip on the BBC today of Dr Bill Frankland, a medical Doctor and still working at 105 years old. He ascribes his continued ability to work to a regime of exercises which he undertakes every morning. The clip is set to a jaunty tune that is meant to lighten the segment and perhaps implies a degree of eccentricity on the good Doctor's part and the article rightly points out that there must have been a degree of biological good fortune in preserving his health and mobility so well and for so long...but...his belief in movement preserving his health is not pure whimsy. Movement can improve the health of almost every bodily system:
Musculo-skeletal - as well as maintaining strength and suppleness of muscles and other soft-tissues and creating the forces which cause your bone to be replenished, most of your joints are lined with hyaline cartilage, which has a very poor blood supply, it is nourished by synovial fluid which is pumped and wiped across the surfaces of the joints during movement through a full range of motion.
Circulatory - The body contains lots of pumps, not just the heart. A well known example is the calf-pump; each time the big calf muscles contract during walking they squeeze the vein lying between them and because of the valves in the vein the blood flows in one direction back to the heart. The heart is designed to operate in conjunction with these pumps, if they aren't operational the heart has to work harder than it should and/or venous return may be compromised causing swelling of the legs and varicose eczema. Of course the main function of the circulatory system is to deliver nutrients and remove waste. Anything that improves circulation will improve the health of every tissue of your body from your brain to your digestive system, to your nerves, skin and sensory organs, not to mention your brain.
Respiratory - Your diaphragm is a muscle and your ribs are joined to your spine with joints, they also have muscles between them. Don't exercise and you'll find you are not able to take as deep a breath as once you were. Less breath, less oxygen, less energy and more CO2 and free-radicals scooting around and potentially causing mischief
Digestive - your digestive system needs to be massaged to maintain health and it achieves that through the movement of the muscles around it
Immune - Your immune system relies on cells moving around, guess how they move, you guessed it, they rely in large part on musculoskeletal pumping through the lymphatic system. Historical records showing that patients in the great flu epidemic 100 years ago survived much better when they had osteopathic treatment, so a recent series of studies set out to understand the mechanisms. Osteopathic pumping techniques were shown to increase the rapidity of immune response and the effectiveness of the immune cells in destroying combating pneumonia and the number of immune cells presented at the site of infection, as well as increasing the number overall...exercise was shown to do the same, the techniques were only repeating the mechanisms the body had created for itself (still very useful in a bedbound patient).
Regular movement has so many life-enhancing and potentially prolonging benefit before you even consider the obvious counteraction of our modern tendency to consume more calories than we burn
Congratulations Dr Frankland. We can learn a lot from you