Caffeine improved cycling trial performance in mentally fatigued cyclists, regardless of alterations in prefrontal cortex activation

Paulo Estevão Franco-Alvarenga; Cayque Brietzke; Raul Canestri; Márcio Fagundes Goethel; Florentina Hettinga; Tony Meireles Santos; Flávio Oliveira Pires

doi:10.1016/j.physbeh.2019.02.009

Caffeine improved cycling trial performance in mentally fatigued cyclists, regardless of alterations in prefrontal cortex activation

Physiol Behav. 2019 May 15:204:41-48. doi: 10.1016/j.physbeh.2019.02.009. Epub 2019 Feb 10.

Authors

Paulo Estevão Franco-Alvarenga¹, Cayque Brietzke¹, Raul Canestri¹, Márcio Fagundes Goethel¹, Florentina Hettinga², Tony Meireles Santos³, Flávio Oliveira Pires⁴

Affiliations

¹ Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil.
² Department of Sport, Exercise, and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom.
³ Federal University of Pernambuco, Recife, Brazil.
⁴ Exercise Psychophysiology Research Group, School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, Brazil; Human Movement Science and Rehabilitation Program, Federal University of São Paulo, Santos, São Paulo, Brazil. Electronic address: [email protected].

PMID: 30742838
DOI: 10.1016/j.physbeh.2019.02.009

Abstract

Purpose: To verify whether caffeine (CAF) could increase the prefrontal cortex (PFC) activation and improve 20 km cycling time trial (TT_20km) performance in mentally fatigued cyclists.

Methods: After preliminary TT_20km, twelve recreational cyclists (VO_2MAX of 58.9 ± 6.2 mL kg min^-1) performed a familiarization with a cognitive test to induce mental fatigue (MF) and psychological scales. Thereafter, they performed: 2) a baseline TT_20km; 3) a mentally fatigued TT_20km (MF); 4 and 5) a mentally fatigued TT_20km after CAF (MF + CAF) or placebo (MF + PLA) ingestion, in a double-blind, counterbalanced design. Performance and psychological responses were obtained throughout the TT_20km, while PFC electroencephalography (EEG) theta wave was obtained before and after the mental fatigue test.

Results: The mental fatigue-induced increase in EEG theta wave (↑ ~ 4.8%) was reverted with CAF (↓ 8.8%) and PLA ingestion (↓ 4.8%). CAF improved TT_20km performance in mentally fatigued cyclists by reducing time (p = .00; ↓ ~ 1.7%) and increasing W_MEAN (p = .00; ↑ ~ 3.6%), when compared to MF + PLA. The RPE-power output ratio was lower (p = .01), but affect (p = .018), motivation (p = .033) and emotional arousal (p = .001) were greater throughout the TT_20km in MF + CAF than in MF + PLA.

Conclusions: CAF ingestion improved TT_20km performance and psychological responses in mentally fatigued cyclists, despite the unaltered PFC activation.

Keywords: Fatigue; Pacing; Placebo; RPE; Supplementation.

Publication types

Randomized Controlled Trial
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Arousal / drug effects
Athletic Performance*
Bicycling*
Caffeine / pharmacology*
Central Nervous System Stimulants / pharmacology*
Cognition / drug effects
Double-Blind Method
Electroencephalography / drug effects
Humans
Male
Mental Fatigue / drug therapy*
Mental Fatigue / psychology*
Motivation / drug effects
Physical Endurance
Prefrontal Cortex / drug effects*
Theta Rhythm / drug effects

Substances

Central Nervous System Stimulants
Caffeine