Panel A shows the microscopic myoarchitecture of the circular and longitudinal muscle layers of the lower esophageal sphincter and stomach. The circular muscle fibers of the esophagus cross each other ...

Micro-organisms in the gut support healthy digestion by helping nerve cells within the intestine to regulate the contraction and relaxation of the muscle wall of the colon, according to new research ...

Muscle contraction is the tightening, shortening, or lengthening of muscles when you do some activity. It can happen when you hold or pick up something, or when you stretch or exercise with weights.