American football: A prolate sphere is about 11 inches long (28 cm) and a circumference of about 22 inches (56 cm) in the center and weighs about 0.875 lbs.
Rugby: A soccer ball prolate. The accepted international size is called “size 5” and is about 27 cm long and 60 cm circumference at its widest point and weighs about 1lb.
United States, Canada Worldwide
What is it? American football is a game with strong physical aggression with players who have speed, power and explosions that require helmet and cushioning. Rugby is a game with strong physical aggression and stamina needed only a mouth guard to play. Some properties require speed and agility, others require strength.
Current World Championship New England Patriots New Zealand All Blacks (Rugby World Cup)
Number of Umpires/Referees 3 to 6 referees plus booth 4 referees including TMO (match officials on television), who claim to test valid or invalid via camera for attempts Not visible to the referee or caused after illegal violations and 2 assistant referees.
Infinite Substitutions Up to 7 substitutions are allowed (subject to the rules of the tournament) Once withdrawn cannot be replaced again unless there is an injury and there is no other replacement.
Player size NFL brandon players bank 70 kg. (155 lbs.) Was at a point of 67 kg. (149 lbs.) The lightest NFL player since 2010 while the largest NFL player is 162, 3kg (358 lbs.) The largest runner is 122kg (268 lbs.) Brandon jacobs. The lightest rugby player ever to play international rugby is Gordon McGhie, who weighs just 58kg. His largest international rugby cavubati (165, 3kg) is heaviest at 201, 7kg (438, 5lbs).
Field Length: 120 yards (109, 728 meters) of total (100 yards (91, 44 meters) of playing field, with two areas ending 10 yards (9,144 meters)) Width: 160 feet (48, 768 meter) 100 (120m if included “target area”) including 70 meter length 70 meters wide with 20 meter test area.
Protective Helmets, shoulder/chest/protective pads, upper leg pads and mouth guards are required. Players are only allowed to moderate cushioning on the Head, Shoulders, Clavicle, etc. Only need mouth protection.