Table A6.

Investigations in multiple sports.

Study	Participants	Habituation to Caffeine	Study Design	Sport	Supplementation	Dose	Main Outcome
Chen et al. (2015) [34]	10 males/19 females 20 ± 2 years	All participants were not regular caffeine consumers (<200 mg·week−1)	DB, R, Cx	Tennis, basketball, and soccer	Energy drink or placebo, consumed 1 h before the exercise	6 mg·kg−1	Significant increase in isometric muscle strength
Rahnama et al. (2010) [58]	10 males 22 ± 2 years	All participants were moderate caffeine users	DB, R, Cx	Not specified	Red Bull energy drink (RB), Hype energy drink (HE), or placebo, consumed 40 min before exercise	RB = 85 mg, HE = 75 mg	Greater VO2max and time to exhaustion
Salinero et al. (2014) [8]	53 males/37 females 24 ± 6 years	All participants were light caffeine consumers (<60 mg·day−1)	DB, R, Cx	Rugby, volleyball, tennis, badminton, swimming, soccer, and hockey	Fure, ProEnergetics energy drink, or placebo, consumed 1 h before exercise	3 mg·kg−1	Increase in self-perceived muscle power during exercise

DB = double-blinded, R = randomized, Cx = crossover, VO_2max = maximum oxygen uptake.