A soccer ball is round, and must measure between 27-28" in circumference and weigh between 14 and 16oz. How big must a soccer field be? What do all the markings mean? What must the pitch be made of?

5 Department of Cardiology, St. Olav’s Hospital, Trondheim, Norway Correspondence to: Dr U Wisløff Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Olav ...