Not so obvious, but one can see for oneself, is that focusing attention on a part of the body during meditation, for example by visualizing breathing directly into the area, will increase circulation in that area. The area will soon feel warmer, look redder, & may swell slightly (eg hands during standing meditation). This is a healthy, parasympathetic "relaxation response."
These next two are more advanced, but make sense and are definitely worth experimenting with.
• Immediately after an acute physical injury (that doesn't require medical or first aid treatment), drop all anger, worry or concern, and know that the injured area will heal perfectly fine on its own, and carry on as if nothing happened. Remember, for millions of years, our ancestors would have behaved precisely this way, even for more severe injuries! It will surprise you how much less pain, swelling, redness, stiffness & loss of function you will experience.
Nowadays, we typically do the opposite - we get mad at ourself or whoever we blame for the accident; get all worried that it will hurt; anxious that it will take a long time - if ever - to heal properly, etc. Such emotional overreactions markedly ramp up the acute inflammatory response: pain, swelling, redness, stiffness, and delay healing - all for a very minor injury that is best simply left alone.
• During an otherwise pleasant musical performance, the couple sitting beside you compulsively text in the dark theater, despite you repeatedly looking at them with disapproval. Your anger steadily mounts with unpleasant fantasies of what you'd like to say / do to them. You feel physically tight & know your blood pressure is elevated. Suddenly you decide to drop all anger, worry & concern, and simply enjoy the show. The tightness & pressure you felt is immediately replaced by looseness, relaxation & gentle tingling throughout your body (felt flow of energy - qi or prana).
It takes practice to suddenly intentionally shift the flow of your energy from fight / freeze / flight (sympathetic nervous system) to relaxation (parasympathetic nervous system), but it's remarkably gratifying & wholesome, and will prevent all manner of short- & long-term problems in your life.
It's disconcerting to realize how many times per hour we mentally, emotionally - & therefore physiologically & in other physical ways - isolate parts of our self from the rest of ourself, or our entire self from other people or the rest of the universe. Unthinkingly, we erect all sorts of these needless conceptual walls, causing us & everyone else endless problems. A classic book on this: Wilber K. "No boundary. Eastern and Western approaches to personal growth." Shambhala, 1979.
But with dedicated, intentional practice we can & will gradually break down all the "walls" (boundaries, armor, ego defences, etc) on which we once depended for survival (or thought we did), but which now are heavy burdens.
During qi gong breathing, we open up all the pores in our body welcoming in fresh air & energy as we breath in. During the out-breath, we release all the stale air, stress & fatigue. We learn to be increasingly porous & open, allowing vital energy to circulate freely, re-establishing normal healthy circulation between ourselves, parts of ourselves, and the universe.
Green Tree by Alice Mason https://www.etsy.com/ca/shop/AliceMasonArtist?ref=l2-shopheader-name