Comparison of Selected Kinetic Variables of Agonist and Antagonist Muscles of Knee in Active Young Women at Open and Closed Kinetic Chain at 60 and 180 Deg/Second

Since the optimization of different forms of exercise and training in exercise and treatment, especially the use of open and close chains, has been discussed in the past studies, the present study was conducted to compare the selected kinetic variables (peak torque, time to torque, average power, and total work) agonist and antagonist muscles of the knee extensor in active women at two open and closed kinetic chain ways at 60 and 180 °sec, respectively.

Participants of the current semi-experimental comparative study included groups of active women. The isokinetic device was used with two special attachments for the open and closed knee movements, while for each type of the test, the device was adapted to the type of test and type of speed and physical physics. The method of testing were first explained to the participants. The information and type of test related to each participant was recorded and stored on the device. For data analysis, mean, standard deviation, and independent T test were used to compare variables as well as the two types of kinetic chain at two speeds with the significance rate set at 0.05.

The results revealed a difference between two open and closed kinetic chain ways with isokinetic device at two speeds of 60 and 180 degrees per second in active group. According to the findings of peak torque, the average power and total work variables in the open kinetic chain in the active group at 60 and 180 degrees per second at two speeds were more in active group and the time of peak torque in closed chain was more than that of open kinetic chain at both speeds.

According to the findings of the study, due to the differences in the results of flexion and extension testing of knee in the open and closed kinetic chains at two speeds of 60 and 180 degrees/s, the results indicated more control and accuracy of the isokinetic test in closed chain in comparison with the open chain at both speeds in the active group. Meanwhile, the results indicated that the time to peak torque of the closed kinetic chain test can be possibly a preference for using this method for post-traumatic rehabilitation; therefore, it is recommended to educators and therapists. Also, due to the higher kinetic values in other variables except for time at both speeds in open kinetic chain, to improve muscle strength and function, performing an open kinetic chain is suitable and useful.