title: The effect of acute pre-workout supplementation on power and strength performance.
abstract: BACKGROUND
  Consumption of pre-workout dietary supplements by both recreational and competitive athletes has increased dramatically in recent years. The purpose of this study was to determine the acute effects of a caffeine-containing pre-workout dietary supplement on various measures of performance including anaerobic power, upper and lower body power, and upper body strength in recreationally trained males.
  
  
  METHODS
  Thirteen males (mean ± SD age = 24 ± 6 yrs; height = 180.3 ± 5 cm; body mass = 83.4 ± 9 kg) participated in this investigation in which they reported to the laboratory on four separate occasions, each separated by one week. Each subject underwent an initial familiarization session on week one followed by baseline (BA) performance testing on week two. Performance testing included a medicine ball put (MBP) to determine upper body explosive power, vertical jump test (VJ) to determine lower body explosive power, one-rep maximum bench press (1-RM) for determining upper body strength, and a Wingate Anaerobic Power Test (WAnT) to determine measures of anaerobic power. On week three, subjects were randomly assigned to ingest either a pre-workout supplement (SUP) or a placebo (PL) and again complete the performance testing protocol. Subjects were provided with the crossover treatment on the fourth and final week. Performance testing commenced 20-minute following ingestion of both treatments, which was similar to previous investigations.
  
  
  RESULTS
  Significant differences in anaerobic peak power relative to the WAnT were observed following ingestion of the SUP (782 ± 191 W) in comparison to the PL (722 ± 208 W; p = 0.003; effect size = 0.30) and BA (723 ± 205 W; p = 0.011; effect size = 0.28). Significant differences were also observed for anaerobic mean power following ingestion of the SUP (569 ± 133 W) in comparison to the PL (535 ± 149 W; p = 0.006; effect size = 0.24) and BA (538 ± 148 W; p = 0.020; effect size = 0.22). No significant differences between trials were observed for upper body power, lower body power, or upper body strength.
  
  
  CONCLUSIONS
  Ingestion of the pre-workout dietary supplement led to significant improvements in anaerobic peak and mean power values in comparison to the placebo and baseline treatments. No improvements were observed in upper and lower body power or upper body strength. Taken prior to exercise, a caffeine-containing pre-workout dietary supplement may improve anaerobic power performance.
authors.affiliation: Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA.
authors.forename: Nic
authors.identifier: 0000-0003-0463-3529
authors.initials: N
authors.lastname: Martinez
authors.affiliation: Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA.
authors.forename: Bill
authors.initials: B
authors.lastname: Campbell
authors.affiliation: Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA.
authors.forename: Madison
authors.initials: M
authors.lastname: Franek
authors.affiliation: Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Buchanan
authors.affiliation: Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Colquhoun
mesh_terms: D015308:Anaerobic Threshold / Q000187:drug effects / Q000502:physiology*; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D015444:Exercise; D005526:Food, Formulated; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000187:drug effects / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology; D010807:Physical Endurance / Q000187:drug effects / Q000502:physiology*; D055070:Resistance Training; D064133:Sports Nutritional Physiological Phenomena; D055815:Young Adult
keywords: Anaerobic power; Dietary supplement; Human performance; Pre-workout; Sports nutrition