the physiology of soccer has been updated, focusing on the physical demands, physiological profiles, and training methods for players and referees. soccer is a popular sport involving players of all ages and skill levels, with performance influenced by technical, tactical, mental, and physiological factors. while players do not need extraordinary abilities in any single area, systematic training and selection have influenced player profiles. soccer is not a science, but scientific approaches can enhance performance. efforts to improve performance often prioritize technique and tactics over physical fitness. during a 90-minute game, elite players run about 10 km at an intensity near the anaerobic threshold. they require numerous explosive actions, including jumping, kicking, and sprinting. the best teams continue to improve their physical capacities, while less ranked teams have similar values as in the past. the role of aerobic capacity is significant, with lower division teams showing comparable aerobic capacities to professional teams. this article provides an update on the physiology of soccer players and referees, along with relevant physiological tests and examples of effective strength and endurance training programs. a review of 9893 papers identified 843 for closer analysis, with 181 selected for discussion. the information has important implications for the safety and success of soccer players, and should be understood and acted upon by coaches and players.the physiology of soccer has been updated, focusing on the physical demands, physiological profiles, and training methods for players and referees. soccer is a popular sport involving players of all ages and skill levels, with performance influenced by technical, tactical, mental, and physiological factors. while players do not need extraordinary abilities in any single area, systematic training and selection have influenced player profiles. soccer is not a science, but scientific approaches can enhance performance. efforts to improve performance often prioritize technique and tactics over physical fitness. during a 90-minute game, elite players run about 10 km at an intensity near the anaerobic threshold. they require numerous explosive actions, including jumping, kicking, and sprinting. the best teams continue to improve their physical capacities, while less ranked teams have similar values as in the past. the role of aerobic capacity is significant, with lower division teams showing comparable aerobic capacities to professional teams. this article provides an update on the physiology of soccer players and referees, along with relevant physiological tests and examples of effective strength and endurance training programs. a review of 9893 papers identified 843 for closer analysis, with 181 selected for discussion. the information has important implications for the safety and success of soccer players, and should be understood and acted upon by coaches and players.