The following link will take you to the preamble of this article, written in Spanish by Juan Ribas: https://www.laktate.com/en/information/technical-issues/lactate-from-undesirable-to-valuable-metabolite-the-role-of-lactate-production-in-the-regulation-of-the-excitability-during-high-power-requirement-in-muscle-fibres/. In this same section you will be able to find a link to access the original article, written in Spanish, where the author attempts to show his current conception of the role of lactate in muscle physiology, with the relevant scientific support.