title: Effect of movement velocity on the relationship between training load and the number of repetitions of bench press.
abstract: This study investigated the effect of movement velocity on the relationship between loading intensity and the number of repetitions of bench press. Thirteen healthy men (age = 21.7 +/- 1.0 years; weight = 76.8 +/- 2.5 kg; 1 repetition maximum [1RM] = 99.5 +/- 6.0 kg), who were involved in regular weight training, voluntarily participated in the experiment. Subjects performed bench presses on a Smith machine at 5 different intensities (40-80% 1RM), repeated for 4 velocity conditions (slow: 0.15 +/- 0.03 m.s(-1); medium: 0.32 +/- 0.07 m.s(-1); fast: 0.52 +/- 0.12 m.s(-1); ballistic: maximum velocity), which were randomly assigned over 5 experimental sessions after a 1RM test. Velocity significantly changed the relationship between intensity (%1RM) and the number of reps performed (p < 0.001), with faster velocities producing a higher number of reps. A significant interaction between intensity and velocity meant that velocity had a much greater effect on repetitions at lower intensities. These results suggest that the benefits of using a stretch-shortening cycle during faster movements outweigh the associated disadvantages from the force-velocity relationship. The practical applications of this study are that, when trainees are assigned a resistance training with specific RM values, the lifted intensity (%1RM) or weights will not be consistent unless velocity is controlled during training.
authors.affiliation: University of Sydney, Faculty of Health Sciences, School of Exercise and Sport Science, Lidcombe, Australia.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Sakamoto
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Sinclair
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D010806:Physical Education and Training / Q000379:methods*; D014891:Weight Lifting / Q000502:physiology*