lost in space,
That's edema. When the body gets too much sodium or loses too little (kidneys and perspiration) the extracellular fluid holds more sodium which the body carefully dilutes to keep the concentration in a VERY narrow range to support life.
THe net result is too much extracellualr fluid and this is felt as high blood pressure (too much fluid in the blood vessels), puffy hands, wrists and ankles (too much fluid fluid outside the vessels) and pain (too much fluid in the joint capsules increasing joint pressure and irritating the nerve linings.)
Less salt or taking diuretics will usually cure the symptoms...1/2 hour in a sauna works wonders too.