title: Effects of antagonist pre-load on knee extensor isokinetic muscle performance.
abstract: The aim of this study was to evaluate and compare acute effects of a reciprocal action protocol and a super-set protocol on knee extensor performance during concentric isokinetic exercise. Fourteen men aged 29.4 ± 6.1 years were tested on three different protocols, with 1 min of rest between sets: control (3 sets of 10 isokinetic knee extension repetitions), reciprocal action protocol (3 sets of 10 repetitions of reciprocal isokinetic concentric knee flexion and knee extension repetitions), and super-set protocol (3 sets of a combination of 10 repetitions of knee flexion immediately followed by 10 repetitions of knee extension repetitions). Tests were performed at 60° · s(-1) and 180° · s(-1), randomized across 3 days and separated by at least 72 h. There were no significant differences between protocols for peak torque at 60° · s(-1) or 180° · s(-1). Total work was significantly higher during the reciprocal action protocol compared with the super-set protocol at 60° · s(-1). There was a significant decline in peak torque (from 240.6 to 212.9 N · m) and total work (from 2294 to 1899 J) for the control condition at 60° · s(-1). Also, total work declined significantly across sets for the super-set protocol at 60° · s(-1) (from 2157 to 1707 J). Results indicate that a reciprocal action protocol provides torque maintenance during multiple sets of isokinetic training, both at slow and high velocities.
authors.affiliation: College of Physical Education, University of Brasilia, Brasilia, Brazil. rodrigocarregaro@yahoo.com.br
authors.forename: Rodrigo L
authors.initials: RL
authors.lastname: Carregaro
authors.forename: Paulo
authors.initials: P
authors.lastname: Gentil
authors.forename: Lee E
authors.initials: LE
authors.lastname: Brown
authors.forename: Ronei S
authors.initials: RS
authors.lastname: Pinto
authors.forename: Martim
authors.initials: M
authors.lastname: Bottaro
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D006801:Humans; D007717:Knee / Q000502:physiology*; D007719:Knee Joint / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D055070:Resistance Training / Q000379:methods*; D055815:Young Adult