The effect of three different energy drinks on oxygen consumption and perceived exertion during treadmill exercise

Methods Fifteen (22.1 ± 2.7 years old) participants completed the study. Maximal oxygen consumption (VO2 max) was initially measured to establish each participant’s exercise for the 70% treadmill exercise protocol after ingesting an energy drink. Following VO2 max testing, all participants completed a total of four conditions. Each condition required a participant to ingest an energy drink then rest in a seated position for one hour. Following one hour of rest, participants exercised for a total of 15 minutes on a treadmill at 70% of their VO2 max. For each condition, participants blindly ingested one of four price-matched beverages (12 oz. placebo (Squirt), 8.4 oz. Red Bull, 16 oz. Monster Energy , 2 oz. 5-hour ENERGY). Relative VO2 (ml.kg min) and RPE (6-20 Borg Scale) were recorded each minute during the treadmill exercise and averaged in five-minute increments and as an average for each 15-minute condition.