title: Effects of a supplement designed to increase ATP levels on muscle strength, power output, and endurance.
abstract: BACKGROUND
  The present study examined the acute effects of a nutritional supplement intended to improve adenosine triphosphate (ATP) concentrations on vertical jump height, isometric strength of the leg extensors, leg extension endurance, and forearm flexion endurance.
  
  
  METHODS
  Twenty-four healthy men (mean age +/- SD = 23 +/- 4 yrs, stature = 181 +/- 7 cm, and body mass = 82 +/- 12 kg) volunteered to complete a familiarization trial plus 2 randomly-ordered experimental trials separated by a 7-day washout period. Participants received either 6 (body mass < 91 kg) or 8 (body mass >/= 91 kg) tablets of the treatment (TR; 625 mg of adenylpyrophosphoric acid and calcium pyruvate, 350.8 mg of cordyceps sinensis extract and yohimbine hydrochloride) or placebo (PL; 980 mg of microcrystalline cellulose) 1 hour prior to the following tests: countermovement vertical jump (CVJ), forearm flexion repetitions to exhaustion, isometric maximal voluntary contractions (MVCs) of the leg extensors, and a 50-repetition maximal concentric isokinetic leg extension endurance test.
  
  
  RESULTS
  There were no differences between the TR and PL trials for CVJ height (P > 0.05), isometric MVC peak torque (P > 0.05), maximal concentric isokinetic peak torque (P > 0.05), percent decline during the leg extension endurance tests (P > 0.05), or repetitions to exhaustion during the forearm flexion endurance tests (P > 0.05).
  
  
  CONCLUSIONS
  These findings indicated no improvements in the measured variables as a result of ingesting this nutritional supplement. Future studies should examine whether chronic supplementation or a loading period is necessary to observe any ergogenic effects of this supplement.
authors.affiliation: Department of Health and Exercise Science, University of Oklahoma, Norman, USA.
authors.forename: Trent J
authors.initials: TJ
authors.lastname: Herda
authors.affiliation: Department of Health and Exercise Science, University of Oklahoma, Norman, USA.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Ryan
authors.affiliation: Department of Health and Exercise Science, University of Oklahoma, Norman, USA.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Stout
authors.affiliation: Department of Health and Exercise Science, University of Oklahoma, Norman, USA.
authors.forename: Joel T
authors.initials: JT
authors.lastname: Cramer