TY - JOUR
T1 - Effects of caffeine on countermovement-jump performance variables in elite male volleyball players
AU - Zbinden-Foncea, Hermann
AU - Rada, Isabel
AU - Gomez, Jesus
AU - Kokaly, Marco
AU - Stellingwerff, Trent
AU - Deldicque, Louise
AU - Peñailillo, Luis
N1 - Publisher Copyright:
© 2018 Human Kinetics, Inc.
PY - 2018/2
Y1 - 2018/2
N2 - Purpose: To examine the effects of a moderate dose of caffeine in elite male volleyball players on countermovement-jump (CMJ) performance, as well as temporal concentric- and eccentric-phase effects. Methods: Ten elite male volleyball players took part in 2 experimental days via a randomized crossover trial 1 wk apart in which they ingested either 5 mg/kg of caffeine or a placebo in double-blind fashion. Heart rate and blood pressure were measured at rest and 60 min postingestion. Afterward, subjects also performed 3 CMJ trials 60 min postingestion, of which the average was used for further analysis. They filled out a questionnaire on possible side effects 24 h posttrial. Results: Caffeine intake, compared with placebo, increased CMJ peak concentric force (6.5% ± 6.4%; P = .01), peak power (16.2% ± 8.3%; P < .01), flight time (5.3% ± 3.4%; P < .01), velocity at peak power (10.6% ± 8.0%; P < .01), peak displacement (10.8% ± 6.5%; P < .01), peak velocity (12.6% ± 7.4%; P < .01), peak acceleration (13.5% ± 8.5%; P < .01), and the force developed at peak power (6.0% ± 4.0%; P < .01) and reduced the time between peak power and peak force (16.7% ± 21.6%, P = .04). Caffeine increased diastolic blood pressure by 13.0% ± 8.9% (P < .05), whereas no adverse side effects were found. Conclusions: The ingestion of 5 mg/kg of anhydrous caffeine improves overall CMJ performance without inducing side effects.
AB - Purpose: To examine the effects of a moderate dose of caffeine in elite male volleyball players on countermovement-jump (CMJ) performance, as well as temporal concentric- and eccentric-phase effects. Methods: Ten elite male volleyball players took part in 2 experimental days via a randomized crossover trial 1 wk apart in which they ingested either 5 mg/kg of caffeine or a placebo in double-blind fashion. Heart rate and blood pressure were measured at rest and 60 min postingestion. Afterward, subjects also performed 3 CMJ trials 60 min postingestion, of which the average was used for further analysis. They filled out a questionnaire on possible side effects 24 h posttrial. Results: Caffeine intake, compared with placebo, increased CMJ peak concentric force (6.5% ± 6.4%; P = .01), peak power (16.2% ± 8.3%; P < .01), flight time (5.3% ± 3.4%; P < .01), velocity at peak power (10.6% ± 8.0%; P < .01), peak displacement (10.8% ± 6.5%; P < .01), peak velocity (12.6% ± 7.4%; P < .01), peak acceleration (13.5% ± 8.5%; P < .01), and the force developed at peak power (6.0% ± 4.0%; P < .01) and reduced the time between peak power and peak force (16.7% ± 21.6%, P = .04). Caffeine increased diastolic blood pressure by 13.0% ± 8.9% (P < .05), whereas no adverse side effects were found. Conclusions: The ingestion of 5 mg/kg of anhydrous caffeine improves overall CMJ performance without inducing side effects.
KW - Nutrition
KW - Power
KW - Rate of force development
UR - http://www.scopus.com/inward/record.url?scp=85045551357&partnerID=8YFLogxK
U2 - 10.1123/ijspp.2016-0705
DO - 10.1123/ijspp.2016-0705
M3 - Article
C2 - 28488924
AN - SCOPUS:85045551357
SN - 1555-0265
VL - 13
SP - 145
EP - 150
JO - International Journal of Sports Physiology and Performance
JF - International Journal of Sports Physiology and Performance
IS - 2
ER -