What can cause a knot in the stomach muscles?

Answer 1

Knots in stomach muscles can be caused by stress and stomach ailments such as gastritis. Another cause of protruding knots on the abdomen wall can also be caused by a hernia, which is a tear in the abdominal sack.

Answer 2

Knots in muscles are usually attributed to what is referred to as taut band, That is a group of muscle fibers that have been shortened and the central part of that "taut band" has resulted in a small section of it being bunched up more tightly than the rest. This knot, or contracted tissue, then prevents the flow of blood to that area, and the resulting loss of oxygen and nutrients then starts to accumulate metabolic toxins. The pain is from the poisons accumulating. Pain is the body's distress call, saying that something is wrong. When tissue does not get what it needs, it becomes painful.

Try and think of it this way: You are having a hard time breathing, are hungry and tired, and everybody else is having a good time. How would you feel? Well, that's what the muscle is experiencing, it is overworked and underfed, and all the neighbors are doing better. I'd be tied up in a knot and complaining too, if I was in that condition.