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49ers Fitness Corner


Assistant strength and conditioning coach Duane Carlisle joined the 49ers this off-season from the Philadelphia Eagles. He is in charge of directing all of the speed, agility, and conditioning programs for all positions on the team. The president and founder of Lighting Fast Training Systems is one of the leaders in the area of athletic performance training. He has spent the last 13 years pushing athletes to perform to their maximum potential.

Each week Carlisle will provide valuable insight into with columns geared toward educating our fans about the latest aspects of; speed development, quickness training, strength and power development, nutrition and general fitness topics. Carlisle has also developed workout videos which can be viewed, by clicking here!

In addition, head strength and conditioning coach Johnny Parker will join Carlisle in answering a few questions from our fans. To have your question considered, please email Carlisle and Parker at

My focus for the next several weeks in these columns will be on how to improve movement. In the game of football the ability to move efficiently, explosively, and quickly in all planes of directions-forward, laterally, diagonally, and backward is critical to the success of our players. This article emphasizes the general principles of movement and in forthcoming articles I will address how to improve position-specific speed, agility, and quickness.

For years, it was believed that athletes were inherently fast or slow. Consequently, the belief that speed was impossible to teach was widely accepted. Another wide-held belief associated with speed is that in order to become faster an athlete must run, run, run. Even today, when asked about the definition of speed, the most common answer is "speed is how fast a person can run."

Speed training counteracts all of the above mentioned beliefs. With the help of modern science, we now know that every individual is born with a certain percentage of fast twitch (fast) and slow twitch (endurance) muscle fibers. Maximizing an athlete's fast twitch potential is the objective of speed development.

Speed development training focuses on maximizing three areas related to an athlete's movement: speed, quickness, and agility. Often, speed, quickness, and agility are thought of as being one in the same. However, they are really three distinct skills that require individual development.

Speed is a term used to describe the velocity at which an athlete is moving. It can be measured forward, backward, laterally and diagonally. Speed and time go hand and hand. Athletes must increase their speed in order to decrease the amount of time it takes to get from point A to point B.

Agility is the athlete's ability to change direction suddenly with minimal loss of speed, balance, and body control. Agility is a complex skill that involves all six fundamental aspects of sport movement (speed, strength, timing, rhythm, balance, and body control).

The term quickness is often used vaguely, like in the context "the athlete is cat-quick." Simply defined, quickness describes the athlete's body limb movement speed, acceleration, reactive ability, and explosiveness. The more athletes improve limb speed, reaction and acceleration, (quickness) the greater the potential to increase their speed.

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