Carlos Castellar has a Degree in Sports Science, a Master's in Physical activity and health, and a PhD in High Level Sports Performance. Castellar is working as a Lecturer in Sport Sciences at the University of Zaragoza, Spain. He is an expert in endurance and ultra-endurance sports. He is a researcher in the research group Training, Physical Activity and Sports Performance. Castellar collaborates in projects with local and regional entities to promote the use of bicycles in the urban and natural environment. He has participated in numerous national and international conferences. He is co-author of 6 JCR scientific papers. Castellar is Professor in the PhD program of the University of Zaragoza. His teaching activity is focused on different topics such as the impact on the body of different sports efforts or the analysis of cyclical endurance sports.