Effects of a supplement designed to increase ATP levels on muscle strength, power output, and endurance

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.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).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.Nutritional supplements are commonly used by recreational and competitive athletes as ergogenic aids to improve their physique and performance capabilities. For example, creatine is a widely used nutritional supplement that has been proven in multiple studies to increase skeletal muscle phosphocreatine and free creatine concentrations, which may enhance the ability to sustain high adenosine triphosphate (ATP) turnover rates during strenuous exercise [1]. As a result creatine supplementation may delay neuromuscular fatigue [2], improve muscle strength and power output [3], and increase muscle size [4]. The various p