An Efficient Method of Key-Frame Extraction Based on a Cluster Algorithm

• Authors: Gavin L. Moir , Bruce W. Graham , Shala E. Davis , John J. Guers , Chad A. Witmer
• Languages of publication: EN

Abstracts

EN

The purpose of the present study was to investigate the effects of different configurations of repetitions within a set of deadlifts on the mechanical variables of concentric force, concentric time under tension, impulse, work, power, and fatigue. Eleven resistance trained men (age: 21.9 ± 1.0 years; deadlift 1 repetition maximum: 183.2 ± 38.3 kg) performed four repetitions of the deadlift exercise with a load equivalent to 90% of 1 repetition maximum under three different set configurations: Traditional (continuous repetitions); Doubles cluster (repetitions 1 and 2, and 3 and 4 performed continuously with a 30 s rest inserted between repetitions 2 and 3); Singles cluster (30 s rest provided between repetitions). The order of the sessions was counterbalanced across the subjects and the mechanical variables were calculated during each repetition from the synchronized signals recorded from force platforms and a motion analysis system. Relative to the Traditional set, the insertion of rest periods in the cluster set configurations resulted in greater time under tension (p < 0.001) and therefore, greater impulse (p < 0.001) during the repetitions. Reductions in power were observed during the cluster sets compared to the Traditional set (p = 0.001). The Doubles cluster set resulted in greater fatigue scores for power compared to the Traditional set (p = 0.04). The influence of cluster sets on mechanical variables appears to be mediated by the mechanical characteristics of the exercise (i.e. stretch-shortening cycle) and the competing physiological mechanisms of fatigue and potentiation.

Keywords

EN

interrepetition rest; fatigue; resistance exercise

• Publisher: De Gruyter Open
• Journal: Journal of Human Kinetics
• Year: 2013
• Volume: 39
• Issue: 1
• Pages: 15-23

Dates

published

1 - 12 - 2013

online

31 - 12 - 2013

Contributors

author

Gavin L. Moir

• Exercise Science Department, East Stroudsburg University. USA.

author

Bruce W. Graham

• Exercise Science Department, East Stroudsburg University. USA.

author

Shala E. Davis

• Exercise Science Department, East Stroudsburg University. USA.

author

John J. Guers

• Exercise Science Department, East Stroudsburg University. USA.

author

Chad A. Witmer

• Exercise Science Department, East Stroudsburg University. USA.

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Identifiers

DOI

10.2478/hukin-2013-0064