Football Guide: Positions, Rules and Health Benefits

NFL football positions carry specific responsibilities ranging from offensive line to special teams. Learn the official size of an NFL football and the health benefits of playing this high-impact sport.

an african american football player in a red and white uniform is jumping up with arms outstretched to catch a football

Main Muscles Used in Football

Published Jul,08 2011 | By Kim Nunley

Football is a sport that requires strength and power in nearly every muscle throughout the body. Both lower- and upper-body muscles are involved in activities like running, jumping, blocking, catching and throwing.

Football Drills to Increase Speed & Agility

Published Jul,08 2011 | By Kim Nunley

To excel at football, you’ve got to have exceptional speed and agility. On offense, you’ll be able to run faster down the field and dodge opponents. Defensively, you’ll be better able to stay on a wide receiver and track down a running back.

Kim Nunley has been screenwriting and working as an online health and fitness writer since 2005. She’s had multiple short screenplays produced and her feature scripts have placed at the Austin Film Festival. Prior to writing full-time, she worked as a strength coach, athletic coach and college instructor. She holds a master's degree in kinesiology from California State University, Fullerton.