As different styles of play come and go, what is regarded by coaches as good player attributes also changes. This happens in any sport, coaches emphasise speed so fast players are needed, strength and players with muscle bulk are sort after.
Michael Lewis looks at this in his book The Blind Side. He looks at American Football and the interesting trend of recent years that means the left tackle is the second highest paid player on the offense behind the quarterback. As teams have come to rely more on the passing game the left tackle has become very important because for a right handed quarterback the left tackle protects the quarterback's blind side, the side most sacks come from. As quarterback salaries have increased the left tackle's salary has also increased. But not just anyone can play left tackle, a very special physical freak is needed and what impressive specimens they are. Players in this role are usually taller that 6 and a half feet (198cm) and weigh more than 300lbs (136kg), and yet have the body control of a ballerina and the foot speed of a boxer.
Lewis follows a future left tackle from high school into college by the name of Michael Oher. At the age of sixteen when we first meet Michael he is 6ft 6in (198cm) and weighs 350lbs (158kg), and is one of the fastest kids over the 40 yard dash, he runs it in 5 seconds. Lewis tells the amazing story of Michael as he overcomes many obstacles to finally be one of the top prospects in college. Oher will probably be drafted into the NFL over the next couple of years so he is a name to watch out for.
You might think this book would only appeal to American Football fans, but sports fans in general will enjoy this book.