Method Sixrteen physically active elderly men and women (age 64.40±3.66) were recruited. The subjects underwent a 12-week knee flexor/extensor isokinetic exercise program of concentric contractions at a velocity of 180 degrees/sec of the both knee twice a week for 12 weeks. Training was carried out on the isokinetic dynamometer. The subjects were evaluated with muscular strength at 90 degrees/sec, endurance at 180 degrees/sec, cardio-pulmonary function, balance, mood and life quality at baseline, 4-week, 8-week and 12-week.

Results
Six of 16 people gave up in the middle of the course, 10 people completed a muscle strengthening exercise program. Muscular strength, balance, mood and life quality improved.

Conclusion Isokinetic exercise of the knee joint muscle was carried out and showed the result of multivalent effect in old age. Therefore strengthening exercise in aged persons was thought to be provided for welfare policy of an aging society as well as personal health improvement.