Abstract
Background: this study examined the effects of caffeine supplementation on anaerobic performance, neuromuscular efficiency and upper and lower extremities fatigue in Olympic-level boxers. Methods: Eight male athletes, members of the Spanish National Olympic Team, were enrolled in the study. In a randomized double-blind, placebo-controlled, counterbalanced, crossover design, the athletes completed 2 test sessions after the intake of caffeine (6 mg·kg−1) or placebo. Sessions involved initial measures of lactate, handgrip and countermovement jump (CMJ) performance, followed by a 30-seconds Wingate test, and then final measures of the previous variables. During the sessions, electromiography (EMG) data were recorded on the gluteus maximus, biceps femoris, vastus lateralis, gastrocnemius lateral head and tibialis anterior. Results: caffeine enhanced peak power (6.27%, p < 0.01; Effect Size (ES) = 1.26), mean power (5.21%; p < 0.01; ES = 1.29) and reduced the time needed to reach peak power (−9.91%, p < 0.01; ES = 0.58) in the Wingate test, improved jump height in the CMJ (+2.4 cm, p < 0.01), and improved neuromuscular efficiency at peak power in the vastus lateralis (ES = 1.01) and gluteus maximus (ES = 0.89), and mean power in the vastus lateralis (ES = 0.95) and tibialis anterior (ES = 0.83). Conclusions: in these Olympic-level boxers, caffeine supplementation improved anaerobic performance without affecting EMG activity and fatigue levels in the lower limbs. Further benefits observed were enhanced neuromuscular efficiency in some muscles and improved reaction speed.
Highlights
Caffeine is one of the five nutritional supplements considered ergogenic aids (EA) with good to strong evidence of benefits in specific sports scenarios [1,2], along with other EA such as beetroot juice, sodium bicarbonate, β-alanine, and creatine
While fewer studies have focused on sports modalities inducing a predominantly anaerobic metabolism than one mostly dependent on oxidative processes, it is emerging that caffeine may have an ergogenic effect on anaerobic efforts [12,13]
Our results show that the ingestion of caffeine in Olympic-level boxers significantly improves anaerobic performance and has a positive effect on neuromuscular efficiency
Summary
Caffeine is one of the five nutritional supplements considered ergogenic aids (EA) with good to strong evidence of benefits in specific sports scenarios [1,2], along with other EA such as beetroot juice, sodium bicarbonate, β-alanine, and creatine. All are included in the classification system for nutritional supplements of the Australian Institute of Sports (AIS) based on the demonstrated level of Nutrients 2019, 11, 2120; doi:10.3390/nu11092120 www.mdpi.com/journal/nutrients. While fewer studies have focused on sports modalities inducing a predominantly anaerobic metabolism than one mostly dependent on oxidative processes, it is emerging that caffeine may have an ergogenic effect on anaerobic efforts [12,13].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
