There are several attributes that separate NFL players from the average player in a Sunday flag football league or even the Division I college player. Professional athletes are decidedly faster and stronger and have more refined on-the-field instincts. Many players point out how much faster the professional game is. Whereas in college, they could get by on sound technique, in the NFL most players were amongst the fastest and most technically sound players on their college teams.
Most NFL players begin playing the sport in Pop Warner and recreation leagues as children. By the time they entered high school, they have a firm grasp of the game and generally outperform their teammates and opponents on the field. They continue their development during high school and begin to garner attention from college coaches. The vast majority of players in the NFL played college football, and most did so at a Division I program. It is at these major programs that players receive the greatest exposure to NFL scouts. Furthermore, they will have the experience of playing against other elite athletes.
Speed & Agility
The NFL, like the NBA, generally attracts some of the most explosive, fast-twitch players, especially at the skill positions (i.e. receivers, and offensive and defensive backfields). Players spend countless hours working out to increase their speed, by doing explosive Olympic lifts such as squats and cleans, as well as plyometric jumps. Additionally, coaches look for players who are agile as straight-line speed is rarely utilized in the course of a game; instead football players rely on cutting and change-of-direction movements. At the NFL Combine, they are tested on their speed and agility during the 40-yard dash and L-drill. Flexibility is a major component of speed and agility training, thus underscoring the importance of stretching.
Upper Body Strength
Aside from working on speed and agility, players also spend a significant amount of time working out to improve their overall strength. There is a certain onus placed on overall strength development in the game. For example, wide receivers need upper body strength to fight off cornerback jams at the line. Similarly, defensive lineman require strength to disengage themselves from their offensive counterparts, and get the ball-carrier as quickly as possible. Among the most popular lifts are dumbbell curls, bench press and seated row.
Outside of superior physical attributes, NFL players also possess certain intangibles like heightened awareness on the field and the mental aptitude to memorize an NFL playbook. Players are tested on the latter category during the Combine, when they are required to pass the Wonderlic test. The objective is to reach a point where the player has a solid grasp of the offensive or defensive schemes, and may simply react as a play develops. Furthermore, players must have the maturity to handle the frenzied lifestyle of a professional athlete.