article 2014 Caffeine bars used as pre-exercise supplements influence endurance performance, energy metabolism and perception of effort in trained cyclists Kuno Hottenrott, Stephan Schulze, Sebastian Ludyga, Stefanie Geissler JournalJournal of Nursing Education and PracticeDOI10.5430/jnep.v4n3p180Publication typeOriginal ResearchPopulationtrained cyclists View on DOI ↗