title: Rowing skill affects power loss on a modified rowing ergometer.
abstract: OBJECTIVE
  In rowing, the athlete has to maximize power output and to minimize energy losses to processes unrelated to average shell velocity. The contribution of velocity efficiency (evelocity; the fraction of mechanical power not lost to velocity fluctuations) to rowing performance in relation to the contributions of maximum oxygen uptake (V[spacing dot above]O2max) and gross efficiency (egross) was investigated. Relationships between evelocity and movement execution were determined.
  
  
  METHODS
  Twenty-two well-trained female rowers participated in two testing sessions. In the first session, they performed a 2000-m time trial on a modified rowing ergometer that allowed for power losses due to velocity fluctuations. The V[spacing dot above]O2max, the evelocity, and the amount of rower-induced impulse fluctuations (RIIF) due to horizontal handle and foot stretcher forces were determined in a steady state part of the time trial. RIIF was used as a measure of movement execution. In the second session, egross was determined at submaximal intensity.
  
  
  RESULTS
  As expected, V[spacing dot above]O2max accounted for the major part of explained variance in the 2000-m time (53%, P < 0.001). Velocity efficiency accounted for a further 14%, egross for 11% (P < 0.05). Negative correlations were found between evelocity and RIIF values of several discreet intervals within a stroke cycle. The results suggest that optimal timing of forces applied to the ergometer will help minimizing power loss to velocity fluctuations.
  
  
  CONCLUSIONS
  This study indicates that a relationship exists between performance and evelocity. Furthermore, evelocity appears to be related to movement execution, in particular the timing of handle and foot stretcher forces.
authors.affiliation: Faculty of Human Movement Sciences, Research Institute MOVE, Vrije Universiteit Amsterdam, The Netherlands. m.hofmijster@fbw.vu.nl
authors.forename: Mathijs J
authors.initials: MJ
authors.lastname: Hofmijster
authors.forename: A J
authors.initials: AJ
authors.lastname: VAN Soest
authors.forename: Jos J
authors.initials: JJ
authors.lastname: DE Koning
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D009048:Motor Skills / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology*; D012767:Ships