Maximal voluntary muscular torque output, total work and endurance ratio of the quadriceps and hamstrings during isokinetic exercise was studied in order to obtain the isokinetic normative data of the knee for clinical use. 160 subjects were tested, from 3rd decade to 6 th decade, 20 men and 20 women in each decade respectively.

The results obtained were as follows:

1) The torque values of males were significantly greater than females at each test speed and in quadriceps and hamstring.

2) The more the age was younger the more the torque values were significantly greater.

3) The quadriceps torque values was significantly greater than the hamstrings at each test speed.

4) The torque values decreased as speed of exercise increased.

5) No significant differences of knee torque values was found between dominant and nondominant limbs.

6) The ratio of hamstring torque values to quardriceps torque values significantly increased as the test speed increased.

7) The total work was significantly decreased in female, old decade and hamstring respectively.

8) The endurance ratio was generally more than 50% except hamstring in 6th decade.

9) The peak torque acceleration energy was significantly decreased in female, old decade and hamstring respectively.

10) The average power was significantly decreased in female, old decade and hamstring respectively.