In this research, the imposed force on three muscles including: Gastrocnemius muscle, Trapezius muscle and Quadratus lumborum muscle of the tractor\\\'s driver during clutching has been studied. The number of sample people was assigned 30 and the research was conducted on two domestic tractors: MF285 and MF399 tractors. The clutching forces for these tractors were measured as 437.2 N and 317.2 N, respectively. The angle of knee location in these two tractors at the one percent level was significantly different. The decrease of pain threshold after 30 seconds and 60 seconds clutching and 60 seconds rest after clutching in MF285 tractor in all three muscles were more than MF399 tractor. In order to reduce the imposed force of clutching for MF285 tractor some modifications is required. In this regard the force transfer joint between the pedal and the disc in the mechanism of clutching can be replaced with the one made of cast iron.

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