When the cardiac muscle is damaged or undergoes a pathological process (e.g. inflammation), its contractile and electrical properties change.
In the retching phase, the abdominal muscles undergo a few rounds of coordinated contractions together with the diaphragm and the muscles used in respiratory inspiration.
When muscles are undergoing strenuous activity, they generate CO and lactic acid as products of cellular respiration and lactic acid fermentation.
The ribs are much thicker than those of similarly sized mammals and the spinal muscles have undergone some radical changes.
As you exercise, muscles undergo a cycle of breakdown during the workout followed by remodeling and growth afterward.
Most insect muscles are phasically responsive (i.e. they contract and relax relatively quickly) but some skeletal and all visceral muscles undergo sustained tonic contractions.
At all methods muscles and tendons undergo stretching stress (various methods only change this stretching conditions).
For example, in the push-off in sprinting, the muscles undergo an explosive shortening contraction (after being pre-tensed) to produce maximum force and resultant running speed.
