British Journal of Nutrition

Full Papers

Human and Clinical Nutrition

The use of energy drinks in sport: perceived ergogenicity and side effects in male and female athletes

Juan J. Salineroa1, Beatriz Laraa1, Javier Abian-Vicena1, Cristina Gonzalez-Millána1, Francisco Arecesa1, César Gallo-Salazara1, Diana Ruiz-Vicentea1 and Juan Del Cosoa1 c1

a1 Exercise Physiology Laboratory, Camilo José Cela University, Castillo de Alarcon, 49 Villafranca del Castillo, Madrid 28692, Spain


The use of caffeine containing energy drinks has dramatically increased in the last few years, especially in the sport context because of its reported ergogenic effect. The ingestion of low to moderate doses of caffeinated energy drinks has been associated with adverse side effects such as insomnia or increased nervousness. The aim of the present study was to assess psycho-physiological changes and the prevalence of side effects resulting from the ingestion of 3 mg caffeine/kg body mass in the form of an energy drink. In a double-blind and placebo controlled experimental design, ninety experienced and low-caffeine-consuming athletes (fifty-three male and thirty-seven female) in two different sessions were provided with an energy drink that contained 3 mg/kg of caffeine or the same decaffeinated energy drink (placebo; 0 mg/kg). At 60 min after the ingestion of the energy drink, participants completed a training session. The effects of ingestion of these beverages on psycho-physiological variables during exercise and the rate of adverse side effects were measured using questionnaires. The caffeinated energy drink increased self-perceived muscle power during exercise compared with the placebo beverage (6·41 (sd 1·7) v. 5·66 (sd 1·51); P= 0·001). Moreover, the energy drink produced a higher prevalence of side effects such as insomnia (31·2 v. 10·4 %; P< 0·001), nervousness (13·2 v. 0 %; P= 0·002) and activeness (16·9 v. 3·9 %; P= 0·007) than the placebo energy drink. There were no sex differences in the incidence of side effects (P>0·05). The ingestion of an energy drink with 3 mg/kg of caffeine increased the prevalence of side effects. The presence of these side effects was similar between male and female participants.

(Received February 19 2014)

(Revised June 13 2014)

(Accepted July 06 2014)

(Online publication September 12 2014)

Key Words:

  • Energy drinks;
  • Side effects;
  • Ergogenic effects;
  • Sport;
  • Sex differences


c1 Corresponding author: J. Del Coso, fax +34 918 153 131, email


  Abbreviations: RPE, rate of perceived exertion