Caffeine ingestion increases estimated glycolytic metabolism during taekwondo combat simulation but does not improve performance or parasympathetic reactivation - Lopes-Silva, João Paulo; Santos, Jonatas Ferreira da Silva; Branco, Braulio Henrique Magnani; Abad, César Cavinato Cal; Oliveira, Luana Farias de; Loturco, Irineu; Franchini, Émerson; Benatti, Fabiana Braga (PLOS ONE, 2015)