Medically reviewed by Katrina Carter, DPT Key Takeaways Voluntary muscles can be controlled by the person, like muscles in your neck and legs. Involuntary muscles work without you thinking about it, ...

A new study by researchers at Yale and Johns Hopkins University has discovered how asthmatic bronchial spasms — muscle contractions in the airway that cause difficulty breathing in asthma patients— ...

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 ...