Effects of Muscle Fatigue on Muscle Latency and Muscle Activation Under Whole-Body Vibration

Whole-body vibration and muscle fatigue have both been shown to delay the trunk muscle reflex response and increase trunk muscle activation, leading to an increased risk of low back injuries. However, the effects of whole-body vibration on previously fatigued trunk muscles have never been tested, despite tests showing that prolonged exposure to wholebody vibration can lead to muscle fatigue. The purpose of this research was to investigate the effects of muscle fatigue on muscle latency, muscle activation and perceived discomfort when exposed to whole-body vibration. The results showed that a fatigued muscle state resulted in increased muscle latency, muscle activation and perceived discomfort, which all escalate the risk of low back injuries. Additionally, the ISO 2631-1 comfort ratings did not increase with fatigue, showing a disconnect between these comfort ratings and the perceived discomfort ratings in a fatigued muscle state.

Year	Entry
1999	Bovenzi M, Hulshof CTJ. An updated review of epidemiologic studies on the relationship between exposure to whole-body vibration and low back pain (1986–1997). Int Arch Occup Environ Health. September 1999;72(6):351-365.
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1997	Mechanical Vibration and Shock: Evaluation of Human Exposure to Whole-Body Vibration, I: General Requirements. ISO Standard ISO 2631-1. [ISO Standard thesis]. Geneva, Switzerland: International Organization for Standardization; 1997.
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Year

Entry

1999

Bovenzi M, Hulshof CTJ. An updated review of epidemiologic studies on the relationship between exposure to whole-body vibration and low back pain (1986–1997). Int Arch Occup Environ Health. September 1999;72(6):351-365.

1990

Boshuizen HC, Bongers PM, Hulshof CTJ. Self-reported back pain in tractor drivers exposed to whole-body vibration. Int Arch Occup Environ Health. February 1990;62(2):109-115.

1997

Mechanical Vibration and Shock: Evaluation of Human Exposure to Whole-Body Vibration, I: General Requirements. ISO Standard ISO 2631-1. [ISO Standard thesis]. Geneva, Switzerland: International Organization for Standardization; 1997.

1990

Griffin MJ. Handbook of Human Vibration. London, UK: Academic Press Limited; 1990.

1992

Panjabi MM. The stabilizing system of the spine, II: neutral zone and instability hypothesis. J Spinal Disord. December 1992;5(4):390-396.