You could explain to them the simple principle of 'If you don't use it, you lose it.' The body likes to conserve resources. So, if some part is not used, the body sends it less nourishment and does not clean out the waste products. In effect, reducing the circulation of blood in that area. Any kind of movement, whether it is passive or active, will encourage the body to provide more circulation to the area and even build up the muscle tone. It is not a substitute for exercise, but it can be considered along the same lines as the benefits of exercise to the body.
he or she passively submits to fate
That is the correct spelling of "passively" (in an indirect way, or in a deferential manner).
passive is the root word for passively.
He passively ignored the questions of probing reporters.
water passively follows salt
Osmosis.
IDS
A high level of salt in a cell would cause water molecules to move passively into the cell.
Passively, via diffusion.
no
The Ascending potion of the henle's loop. Since it it is impermeable to water but permeable to electrolytes.
i show assertive feelings