Hot and Cold Water Immersion
Hot and Cold Water Immersion is a method used primarily to stimulate bloodflow to extremeties, like the hands, legs, feet, etc. There are reports of people with affected limbs from diabetes, gangrene, and other maladies being saved using only this method. It is also valuable to fight lymph node swelling, edema of the limbs, and other circulation disorders. It generally produces a noticeable improvement in hours if not immediately.
The method is to immerse a limb or other body part in water as hot as is comfortable. Leave for 3 minutes. Add more hot water as tolerance to the high heat increases. Remove limb and immerse in very cold water, preferably in the 32-40 degree F range (water with some ice cubes), for 30 seconds. Repeat hot/cold immersion two more times and end with three minutes in hot water. Massage after and/or during immersion.
For whole body use, this is not practical, although some of the same benefit can be had by alternating between a hot tub and a cold pool. Just taking hot baths, preferably with water jets, works well enough. Using epsom salts (magnesium sulfate) in the water usually makes it more effective and can greatly assist therapy for some even serious disorders. Other additions can include baking soda or sea/mineral salt. If this is an ongoing therapy, try all three to see which works best.
If it is not practical to use hot and cold water on the area, much of the same benefit can be had from using a heating pad and an ice pack instead of the hot and cold water.