Georgia Hunter said...
Basically, swelling is caused by two things, cardiac insufficiency or renal insufficiency.
Depends if its blood or just water/non blood fluid. Some examples:
If its blood swelling in the legs- there can be leg vein valve insufficiency. This can be seen in ultra sound - this use for US new in the medical field, very few places can/know how to detect it. Even athletes can get it.
Genes- there are clotting genes. People with this, no matter how active they are can get deep leg clots or superficial clot (not deep) which causes swelling too.
Lymph fluid too- there are massages for this