Final answer:
Peristalsis is the involuntary system of muscle contractions that moves waste matter through the digestive system. This process assists in the digestion, absorption, and elimination of waste, which includes the movement of feces through contractions of the rectal muscles assisted by the voluntary Valsalva's maneuver.
Step-by-step explanation:
A system of massage which moves waste matter through the body is called peristalsis. Peristalsis involves rapid, involuntary, wave-like contractions of smooth muscles. This process occurs naturally in our bodies and pushes food through the gastrointestinal tract, as well as urine through the urinary tract. In the digestive system, peristalsis helps to move food along the tract, aids the body in digesting food, absorbing nutrients, and eventually in the elimination of waste.
The Valsalva's maneuver is a voluntary process that assists in the elimination of feces by increasing intra-abdominal pressure to facilitate the expulsion of waste through the anus by contracting the diaphragm and abdominal wall muscles. It should be noted that while peristalsis is an involuntary process, some massage therapies are designed to mimic this action to help in reducing waste buildup in the body.