1978 Volume 22 Issue 6 Pages 343-349
The purpose of this study was to observe the difference of training effect on the absolute muscle strength between static and dynamic strength training. The subjects were 14 adult males of whom 7 were exposed to static training and others to dynamic training. All subjects were trained every day for 12 weeks except Sundays. Training intensity was two-thirds of maximum isometric strength in static training group (S-group) and two-thirds of one repetition maximum (1RM) in dynamic training group (D-group). In S-group muscle strength was exerted statically for 1O seconds on the right angle of the elbow joint. In D-group the elbow joint was flexed between 75 and 105 degrees of the angle of elbow joint with the rhythm of one repetition in two seconds using audiovisual metronome, and it was repeated five times in a set. All training exercises for both groups were given three sets in a day. The cross-sectional area of elbow flexor muscle was measured at the extended position of the elbow joint before and after training by means of ultrasonic method, and the absolute muscle strength was calculated. The results were as follows: 1)Maximum isometric strength significantly increased (p < 0.001) by 25.9±4.2% (mean ± standard error) in S-group and 30.7±3.8% in D-group. No significant difference of strength increase was observed between dynamic and static training group. 2)The dynamic strength, measured as 1RM significantly increased (p < 0.001) by 22.7±1.1% in S-group and by 33.1±4.0% in D-group. The increase of 1RM in D-group was significantly higher than that in S-group. 3)1RM was about 70% of isometric maximum strength, which value was not affected by both training programs. 4)Cross-sectional area of muscle increased significantly by 5.4±1.4% (p < 0.01) in S-group and 3.2±1.3% (p < 0.05) in D-group. No significant difference in increase of muscle area was observed between S- and D-group. 5)Absolute muscle strength increased by training up to about 9.7kg/cm^2 (muscle area measured at extended position of elbow joint) in both training groups.