Chapter 19 of the Essentials of Strength Training and Conditioning covers all of the major steps involved in designing a speed and agility program.

Many of the same steps are involved in program design for resistance and aerobic endurance training.

Program Design and Technique for Speed and Agility Training

• Speed - the skill and ability to accelerate and reach high movement velocities.
• Change-of-Direction - the skill and abilities needed to change movement direction, velocity or modes. This is predetermined like running a route.
• Agility - the skill and abilities needed to change movement direction, velocity or modes in response to a stimulus like a coach blowing a whistle or pointing.
• Strength - the ability to produce force.
• Each of these abilities may overlap but, they are not all always present in sport. The coach must be aware of which is required for each sport.
• There is a limited amount of time to produce force so while strength is important, maximal strength does not contribute as much to speed, change of direction and agility.

Speed and Agility Mechanics

• Rate of Force Development - how fast an athlete can generate maximal force. Typically used as an index for explosive strength. Change in force divided by change in time.
• Impulse - the net result of force over time at the time required for its production. The area under the force time curve. The amount of force that is being generated at the given time.
• Force - a relationship between two physical objects. A mass times the amount of acceleration present.
• Acceleration - the rate of change in velocity with respect to time.
• Velocity - how fast an object is traveling and which direction it is traveling in.
• Momentum - the relationship between the mass of an object and the velocity of movement.
• Impulse and RFD are direct measures that provide insight. Power is not discussed because it is not clear whether that value has been reached as a result of force or velocity.

Neurophysiological Basis for Speed

• Strength, plyometric and sprint training in combination produces changes in the neuromuscular system that may help improve sprint performance.
• Strength training works to enhance neural drive, the speed and amplitudes of impulses sent from the nervous system to muscles.
• Stretch-Shortening Cycle (SSC) - a three phased muscle action that is manipulated in this chapter to create powerful movements. Phase I is eccentric and involves loading the SEC with stored energy via a stretch and muscle spindle activation. Phase II is a transitional pause phase called amortization. Phase III is a concentric muscle action that takes advantage of all of the stored energy.
• Training to improve the SSC should involve both brief work bouts or clusters that manage fatigue and aim to keep quality high as well as skillful multi joint movements that transfer force through the kinetic chain and utilize elastic reflexive mechanisms.
• Complex Training - alternating heavy resistance training exercises with SSC tasks aiming to take advantage of the postactivation potentiation effect.
• Postactivation Potentiation - a change in the strength of a nerve impulse caused by stretch. Force is increased due to the demands of the previous contraction. Ex. Jumping higher after a heavy squat.
• Spring-Mass Model (SMM) - a model that illustrates sprinting as an action where the displacement of body mass as the result from energy produced and transferred into the ground by the spring like action of muscles. One spring compresses and then propels the body forward as the other swings.

Running Speed

• Sprinting - a series of flight and stride phases grouped together in an attempt to maximally propel the athlete forward at maximal acceleration, velocity or both.
• The amount of vertical force applied to the ground is the largest difference between the novice and elite sprinters.
• Recovery - after a foot strike when the leg is cycling back through the air towards the butt.
• Ground Preparation - the time before a foot strike.
• Emphasize brief ground support times to achieve a rapid stride rate.
• Emphasize developing the SSC to help increase the amplitude of impulse in each stride of the sprint. The complete Olympic lifts and variations are key for overloading the SSC.

Agility Performance and Change-of-Direction Ability

• Change-of-direction and agility performed at shallow cutting angles (less than 75 degrees) with shorter ground contact times will benefit from training in the same manner as speed training with an added cognitive wrinkle.
• Agility and change-of-direction performed at aggressive angles (75 degrees or greater) with greater than 250ms ground contact times benefit from eccentric and maximal strength alongside concentric explosiveness.
• Tests like the L test require maintaining velocity and bending and can be considered more tests of maneuverability.
• In agility training, focus attention towards the opponent's shoulders, trunk and hips and move the body into positions that allow force to be expressed braking and accelerating.

Methods of Developing Speed

• Demonstrating speed is a result of a good periodized program focused on the right qualities at the right times.
• No exercise improves sprinting more than maximum-velocity sprinting.
• Strength is important because sprinting relies on the ability to direct large amounts of force into the ground in a brief period of time. This should be done as specific as possible to transfer training to sprinting performance.
• Sufficient mobility allows the athlete to reach optimal positions to express the physical characteristics needed for successful performance.

Methods of Developing Agility

• Strength should emphasize relative strength and other speed-strength qualities, especially eccentric strength. It will take some time for newly gained strength to transfer into performance gains.
• Change-of-direction as drills can be periodized to progress from simple to more advanced adding in more cognitive layers.

Program Design

• Periodization - short, medium and long term planning of phases of training to achieve a specific goal at a specific time. Often peak performance at a competition date or period of time.

Speed Development Strategies

• Speed should be periodized in the same way that strength is.
• High speed cameras and laser timers are recommended for assessing sprint performance in monitoring.

Agility Development Strategies

• Agility is also best developed using a periodized approach as opposed to random selection of agility drills. Progression should more from change-of-direction drills to specific tests of agility.
• Tests of maneuverability can also be considered separately.
• If high end three-dimensional motion analysis equipment is not available, high speed cameras (more than 10 frames per second) and timers may be used to monitor.