If you have severe back pain, whether acute, recurring, or chronic (long-term), it may lead to muscle spasms, which are sudden, involuntary contractions of a muscle that can be very uncomfortable.

It is caused by the disruptions of signals from nerve cells of the spinal cord (called motor neurons) to skeletal muscles that control body movements. Possible causes include spinal cord injury, ...

Edited by Kurt Beam, University of Colorado Anschutz Medical Center, Aurora, CO; received September 3, 2024; accepted February 20, 2025 ...

Building muscle mass requires a consistent strength training routine, and it's a process that takes time. Social media makes it seem like quick results are the norm -- yes, some people gain muscle ...

Skeletal muscle fibers display a wide diversity in size both within individual muscles and among different muscles. This heterogeneity in muscle fiber diameter is initiated during development and ...