Search results
Results from the WOW.Com Content Network
A fused tetanic contraction is the strongest single-unit twitch in contraction. [6] When tetanized, the contracting tension in the muscle remains constant in a steady state. This is the maximal possible contraction. [3] During tetanic contractions, muscles can shorten, lengthen or remain constant length. [7]
Tetany or tetanic seizure is a medical sign consisting of the involuntary contraction of muscles, which may be caused by disorders that increase the action potential frequency of muscle cells or of the nerves that innervate them.
Local tetanus is an uncommon form of the disease, in which people have persistent contraction of muscles in the same anatomic area as the injury. The contractions may persist for many weeks before gradually subsiding. Local tetanus is generally milder; only about 1% of cases are fatal, but it may precede the onset of generalized tetanus. [1]
The rate at which the nerve impulses arrive is known as the motor unit firing rate and may vary from frequencies low enough to produce a series of single twitch contractions to frequencies high enough to produce a fused tetanic contraction. Generally, this allows a 2 to 4-fold change in force.
Depiction of smooth muscle contraction. Muscle contraction is the activation of tension-generating sites within muscle cells. [1] [2] In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding something heavy in the same position. [1]
This is a popular state equation applicable to skeletal muscle that has been stimulated to show Tetanic contraction. It relates tension to velocity with regard to the internal thermodynamics. The equation is (+) (+) = (+), where is the tension (or load) in the muscle
The rate of muscle twitch contractions and relaxations are thermally dependent (Q 10 of 2.0-2.5), whereas maximum contraction, e.g., tetanic contraction, is thermally independent. [ 6 ] Muscles of some ectothermic species. e.g., sharks, show less thermal dependence at lower temperatures than endothermic species [ 4 ] [ 7 ]
Time to peak of a twitch contraction (response to a single nerve impulse) FF — Fast fatigable — high force, fast contraction speed but fatigue in a few seconds. FR — Fast fatigue resistant — intermediate force, fatigue resistant — fast contraction speed and resistant to fatigue. FI — Fast intermediate — intermediate between FF and FR.