title: Player Load, Acceleration, and Deceleration During Forty-Five Competitive Matches of Elite Soccer.
abstract: The use of time-motion analysis has advanced our understanding of position-specific work rate profiles and the physical requirements of soccer players. Still, many of the typical soccer activities can be neglected, as these systems only examine activities measured by distance and speed variables. This study used triaxial accelerometer and time-motion analysis to obtain new knowledge about elite soccer players' match load. Furthermore, we determined acceleration/deceleration profiles of elite soccer players and their contribution to the players' match load. The data set includes every domestic home game (n = 45) covering 3 full seasons (2009, 2010, and 2011) for the participating team (Rosenborg FC), and includes 8 central defenders (n = 68), 9 fullbacks (n = 83), 9 central midfielders (n = 70), 7 wide midfielders (n = 39), and 5 attackers (A, n = 50). A novel finding was that accelerations contributed to 7-10% of the total player load for all player positions, whereas decelerations contributed to 5-7%. Furthermore, the results indicate that other activities besides the high-intensity movements contribute significantly to the players' total match workload. Therefore, motion analysis alone may underestimate player load because many high-intensity actions are without a change in location at the pitch or they are classified as low-speed activity according to current standards. This new knowledge may help coaches to better understand the different ways players achieve match load and could be used in developing individualized programs that better meet the "positional physical demands" in elite soccer.
authors.affiliation: 1Department of Physical Education, Nord Trøndelag University College, Levanger, Norway; 2Strømsgodset Toppfotball, Drammen, Norway; 3Center for Elite Sports Research, Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway; 4Rosenborg FC, Trondheim, Norway; 5Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway; and 6Norwegian Center of Football Excellence, Oslo, Norway.
authors.forename: Terje
authors.initials: T
authors.lastname: Dalen
authors.forename: Jørgen
authors.initials: J
authors.lastname: Ingebrigtsen
authors.forename: Gertjan
authors.initials: G
authors.lastname: Ettema
authors.forename: Geir Havard
authors.initials: GH
authors.lastname: Hjelde
authors.forename: Ulrik
authors.initials: U
authors.lastname: Wisløff
mesh_terms: D000054:Acceleration; D061725:Accelerometry / Q000295:instrumentation; D000328:Adult; D054874:Athletic Performance / Q000502:physiology; D003654:Deceleration; D006801:Humans; D012420:Running / Q000502:physiology*; D012916:Soccer / Q000502:physiology*; D013996:Time and Motion Studies