title: The effects of varying resistance-training loads on intermediate- and high-velocity-specific adaptations.
abstract: The purpose of this study was to compare changes in velocity-specific adaptations in moderately resistance-trained athletes who trained with either low or high resistances. The study used tests of sport-specific skills across an intermediate- to high-velocity spectrum. Thirty NCAA Division I baseball players were randomly assigned to either a low-resistance (40-60% 1 repetition maximum [1RM]) training group or a high-resistance (70-90% 1RM) training group. Both of the training groups intended to maximallv accelerate each repetition during the concentric phase (IMCA). The 10 weeks of training consisted of 4 training sessions a week using basic core exercises. Peak force, velocity, and power were evaluated during set angle and depth jumps as well as weighted jumps using 30 and 50% 1RM. Squat 1RMs were also tested. Although no interactions for any of the jump tests were found, trends supported the hypothesis of velocity-specific training. Percentage gains suggest that the combined use of heavier training loads (70-90% 1RM) and IMCA tend to increase peak force in the lower-body leg and hip extensors. Trends also show that the combined use of lighter training loads (40-60% 1RM) and IMCA tend to increase peak power and peak velocity in the lower-body leg and hip extensors. The high-resistance group improved squats more than the low-resistance group (p < 0.05; +22.7 vs. + 16.1 kg). The results of this study support the use of a combination of heavier training loads and IMCA to increase 1RM strength in the lower bodies of resistance-trained athletes.
authors.affiliation: American Sports Medicine Institute, Birmingham, Alabama 35294, USA.
authors.forename: K
authors.initials: K
authors.lastname: Jones
authors.forename: P
authors.initials: P
authors.lastname: Bishop
authors.forename: G
authors.initials: G
authors.lastname: Hunter
authors.forename: G
authors.initials: G
authors.lastname: Fleisig
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001490:Basketball / Q000502:physiology*; D006801:Humans; D008297:Male; D010806:Physical Education and Training / Q000379:methods*; D014741:Video Recording