Muscle tone

In physiology, medicine, and anatomy, muscle tone (residual muscle tension or tonus) is the continuous and passive partial contraction of the muscles, or the muscle's resistance to passive stretch during resting state.^[1]^[2] It helps to maintain posture and declines during REM sleep.^[3] Muscle tone is regulated by the activity of the motor neurons and can be affected by various factors, including age, disease, and nerve damage.

^ O’Sullivan, S. B. (2007). Examination of motor function: Motor control and motor learning. In S. B. O’Sullivan, & T. J. Schmitz (Eds), Physical rehabilitation (5th ed.) (pp. 233-234). Philadelphia, Pennsylvania: F. A. Davis Company.
^ Ganguly, J; Kulshreshtha, D; Almotiri, M; Jog, M (16 April 2021). "Muscle Tone Physiology and Abnormalities". Toxins. 13 (4): 282. doi:10.3390/toxins13040282. PMC 8071570. PMID 33923397.
^ Tinguely, Gilberte; Huber, Reto; Borbély, Alexandera; Achermann, Peter (2006). "Non-rapid eye movement sleep with low muscle tone as a marker of rapid eye movement sleep regulation". BMC Neuroscience. 7: 2. doi:10.1186/1471-2202-7-2. PMC 1389709. PMID 16401347.

[osullivan-1] O’Sullivan, S. B. (2007). Examination of motor function: Motor control and motor learning. In S. B. O’Sullivan, & T. J. Schmitz (Eds), Physical rehabilitation (5th ed.) (pp. 233-234). Philadelphia, Pennsylvania: F. A. Davis Company.

[Ganguly-2] Ganguly, J; Kulshreshtha, D; Almotiri, M; Jog, M (16 April 2021). "Muscle Tone Physiology and Abnormalities". Toxins. 13 (4): 282. doi:10.3390/toxins13040282. PMC 8071570. PMID 33923397.

[tinguely-3] Tinguely, Gilberte; Huber, Reto; Borbély, Alexandera; Achermann, Peter (2006). "Non-rapid eye movement sleep with low muscle tone as a marker of rapid eye movement sleep regulation". BMC Neuroscience. 7: 2. doi:10.1186/1471-2202-7-2. PMC 1389709. PMID 16401347.

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