The purpose of this study was to investigate isokinetic values and cardiovascular responses of hip abductors and adductors in 34 normal untrained subjects(age 26,7±3.1; female 17, male 17) at rest and during separate session of upright and side-lying isokinetic exercises at angular velocity of 30°/sec using isokinetic dynamometer, Cybex 6000.

The results were as follows;

1) The peak isokinetic torque ratio of hip adductors to abductors in upright exercise was 122.8±14.2%, and 85.3±12.6% in side-lying exercise which showed a significant difference in torque values according to positions(p<0.01).

2) Angle of peak torque occurred in upright and side-lying exercises for hip adductors were 29.0±5.3° and 27.9±6.5° respectively , and for hip abductors -0.2±3.1° and -1.7±3.6° respectively which did not show any significant difference between upright and side-lying positions of isokinetic exercise.

3) Heart rate and diastolic blood pressure measured at rest showed a difference between upright and side-lying positions at rest(p<0.01).

However, systolic pressure at rest did not show any significant difference between upright and side-lying positions of isokinetic exercise(p<0.01).

4) In the upright exercise, the increment ratio of heart rate, systolic, and diastolic blood pressures obtained were found to be higher than in the side-lying exercise(p<0.01).

These findings indicate that upright isokinetic exercise of hip abductors and adductors produces a higher afterload than the side-lying maneuver and different positions of exercise may affect isokinetic peak torque values as well.

Therefore, these variables must be considered when prescribing a isokinetic exercise of hip abductor and adductor muscles.