Aim: The present study was aimed at investigating the effect of Red Bull Energy drink (RB) on muscle endurance and fatigue.
Methods: Twenty students of second year MBBS (males N.=10, females N.=10) were involved in a cross over design separated by 7 days, where they received either RB (caffeine at 2 mg/kg body weight) or isoenergetic, isovolumetric, noncaffeinated control drink (CD). After one hour of intake of the drink, maximum isometric force (MVC) and electromyogram (EMG) (flexor carpi radialis) were recorded from the dominant hand using Biopac Systems. After MVC, all subjects performed a sustained isometric contraction at 75% of MVC to fatigue. The Root mean square amplitude (RMS) and mean frequency (MNF) were calculated from the EMG data. Statistical analysis was done using r within and across groups.
Results: Following consumption of RB, the fatigue task showed a decreased tendency to fatigue based on the MNF value for both the drinks. However the EMG index with reference to RMS was inconclusive to interpret any delaying effect on fatigue. There was no significant difference between the two drinks in the parameters assessed during MVC and endurance time.
Conclusion: The Red Bull energy drink (caffeine at 2 mg/kg body weight) was no better than CD at significant delaying effect on fatigue during isometric contraction.