The way the weighted blanket helps sore muscles is that its weight compresses the muscles. The act of compression causes the circulation to increase. The more oxygenated blood that gets to the sore muscle, the sooner it will cease to be achy.
Weighted Blanket Sore Muscles, as the oxygenated blood continues to circulate to and from the sore muscle, the area in question begins to heal. These same blankets are used in deep pressure therapy to relax the nervous system and relieve anxiety. Used as a sore muscle therapy, they initiate similar responses from the body. Delayed onset muscle soreness will seem at its most painful after 24 to 72 hours. So, keep that weighted blanket ready for use.
Fresh blood will naturally flow more readily as your body responds to the pressure initiated by the weight of the blanket. You will benefit by waking the next day to muscles that no longer ache.