EARLY PHASE DIFFERENTIAL-EFFECTS OF SLOW AND FAST BARBELL SQUAT TRAINING

To examine the importance of resistance training movement speed, two g roups of women (24 +/- 4 years, 162 +/- 5 cm, 59 +/- 7 kg) squatted re peatedly at 1) 2 seconds up, 2 seconds down (slow, N = 11); or 2) 1 se cond up, 1 second down (fast, N = 10), doing three warm-up sets and th ree eight-repetition maximum sets, three times per week for 7 weeks. T ests included force platform and video analysis of the vertical jump, long jump, and maximum squat, and isometric and isokinetic knee extens or testing at speeds from 25 to 125 deg/sec. The groups improved simil arly in many variables with training but also showed some differences. In the long jump, the fast group was superior in numerous variables i ncluding knee peak velocity and total-body vertical and absolute power . In the vertical jump, fast training affected the ankle and hip more (e.g., average power), and slow training mostly affected the knee (ave rage torque). in isokinetic testing, the fast group improved strength most at the faster velocities, while the slow group strength changes w ere consistent across the velocities tested. Although both slow and fa st training improved performance, faster training showed some advantag es in quantity and magnitude of training effects.