title: Contrast loading: power output and rest interval effects on neuromuscular performance.
abstract: OBJECTIVE
  This study examined the effect of rest interval after the execution of a jump-squat set with varied external mechanical-power outputs on repeated-jump (RJ) height, mechanical power, and electromyographic (EMG) activity.
  
  
  METHODS
  Twelve male volleyball players executed 6 RJs before and 1, 3, 5, 7, and 10 min after the execution of 6 repetitions of jump squats with a load: maximized mechanical-power output (Pmax), 70% of Pmax, 130% of Pmax, and control, without extra load.
  
  
  RESULTS
  RJ height did not change (P = .44) after the jump squats, mechanical power was higher (P = .02) 5 min after the 130%Pmax protocol, and EMG activity was higher (P = .001) after all exercise protocols compared with control. Irrespective of the time point, however, when the highest RJ set for each individual was analyzed, height, mechanical power, and EMG activity were higher (P = .001-.04) after all loading protocols compared with control, with no differences observed (P = .53-.72) among loads.
  
  
  CONCLUSIONS
  Rest duration for a contrast-training session should be individually determined regardless of the load and mechanical-power output used to activate the neuromuscular system. The load that maximizes external mechanical-power output compared with a heavier or a lighter load, using the jump-squat exercise, is not more effective for increasing jumping performance afterward.
authors: Dept of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece.
authors: Konstantinos
authors: K
authors: Sotiropoulos
authors: Ilias
authors: I
authors: Smilios
authors: Helen
authors: H
authors: Douda
authors: Marios
authors: M
authors: Chritou
authors: Savvas P
authors: SP
authors: Tokmakidis
mesh_terms: D000293:Adolescent; D054874:Athletic Performance; D018592:Cross-Over Studies; D004576:Electromyography; D006115:Greece; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology*; D064797:Physical Conditioning, Human / Q000379:methods*; D020127:Recovery of Function; D013647:Task Performance and Analysis; D013997:Time Factors; D054798:Volleyball; D055815:Young Adult