Caffeine Increased Muscle Endurance Performance Despite Reduced Cortical Activation and Unchanged Neuromuscular Efficiency and Corticomuscular Coherence

Autor(es)

Franco-Alvarenga, Paulo Estevao ^{[1, 2]} ; Brietzke, Cayque ^[1] ; Canestri, Raul ^[1] ; Goethel, Marcio Fagundes ^[1] ; Viana, Bruno Ferreira ^{[1, 3]} ; Pires, Flavio Oliveira ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Arts Sci & Humanities, Exercise Psychophysiol Res Grp, BR-03828000 Sao Paulo, SP - Brazil

^[2] Univ Estacio Sa, Phys Educ, BR-27515010 Resende, RJ - Brazil

^[3] Augusto Motta Univ Ctr, Rehabil Sci Grad Program, BR-21041010 Rio De Janeiro - Brazil

• Tipo de documento: Artigo Científico
• Fonte: NUTRIENTS; v. 11, n. 10 OCT 2019.
• Citações Web of Science: 0

Resumo

The central and peripheral effects of caffeine remain debatable. We verified whether increases in endurance performance after caffeine ingestion occurred together with changes in primary motor cortex (MC) and prefrontal cortex (PFC) activation, neuromuscular efficiency (NME), and electroencephalography-electromyography coherence (EEG-EMG coherence). Twelve participants performed a time-to-task failure isometric contraction at 70% of the maximal voluntary contraction after ingesting 5 mg/kg of caffeine (CAF) or placebo (PLA), in a crossover and counterbalanced design. MC (Cz) and PFC (Fp1) EEG alpha wave and vastus lateralis (VL) muscle EMG were recorded throughout the exercise. EEG-EMG coherence was calculated through the magnitude squared coherence analysis in MC EEG gamma-wave (CI > 0.0058). Moreover, NME was obtained as the force-VL EMG ratio. When compared to PLA, CAF improved the time to task failure (p = 0.003, d = 0.75), but reduced activation in MC and PFC throughout the exercise (p = 0.027, d = 1.01 and p = 0.045, d = 0.95, respectively). Neither NME (p = 0.802, d = 0.34) nor EEG-EMG coherence (p = 0.628, d = 0.21) was different between CAF and PLA. The results suggest that CAF improved muscular performance through a modified central nervous system (CNS) response rather than through alterations in peripheral muscle or central-peripheral coupling. (AU)

• Processo FAPESP: 16/16496-3 - Efeitos do bochecho de carboidrato sobre o desempenho físico e respostas psicofisiológicas de indivíduos mentalmente fadigados durante teste de VO2MÁX
• Beneficiário: Flávio de Oliveira Pires
• Modalidade de apoio: Auxílio à Pesquisa - Regular