摘要:International Journal of Exercise Science 9(5): 685-693, 2016. The purpose was to examine the effects of a 5-Hour ENERGY® shot (5HES) on aerobic performance in recreational athletes. Maximal Aerobic capacity (VO2max), substrate utilization and time to fatigue were determined in twenty-three male participants (21.7±3.3 years, Mean±SD), with a BMI of 25.6±3.7 kgm-2(Mean±SD). Each participant was tested twice in a randomised, double-blind cross-over study design, during which participants were provided with either a 5HES or a placebo shot to ingest prior to exercise. Participants completed a VO2 max treadmill test with RER and RPE values also being measured. Ingestion of a 5HES shot before exercise had no effect on peak VO2 (p=0.194), peak heart rate (p=0.507), peak RER (p=0.678), peak ventilation (p=0.056), and running time to exhaustion (p=0.091) as compared with the ingestion of a placebo shot before exercise. Test results also showed that at the end of each stage there was no difference between heart rate and RER, with P values ranging from 0.226 to 1.000, with an exception being RER at 6 minutes, where p=0.009. The results of this study indicate a 5HES shot before exercise does not have an effect on oxygen consumption, heart rate, or substrate utilization during submaximal and maximal exercise.