jueves, 23 de octubre de 2014

C h a p t e r N i n e. Training Sprinters (2/3)

TESTING AND EVALUATION
It is common for coaches to create a single master training plan for all of their sprinters. Certainly, we should expect some commonalties to exist when the training programs of sprinters are compared. However, only by respecting and addressing the unique qualities and objectives of each athlete can coaches lead them towards achieving their highest levels of performance. Just as a physician examines each patient to properly attend to the individual needs, so must the coach explore the personal capacities of each athlete under his/her charge. Before a training program can be developed, we should “test for success” and look past obvious, surface-level data to explore the depths of undiscovered potential. We will introduce tests that examine both psychological and physiological performance factors.

PSYCHOLOGICAL EVALUATION
We must realize that even if a coach creates a perfect training program to develop the physiological potential of a particular athlete, little will be accomplished if that athlete’s goals and perceptions do not line up with those of the coach. If a coach wants to win a national championship, but the athlete is just looking for a better fit of his or her bathing suit, the conflicting objectives will make for a difficult and unsuccessful relationship. The evaluation process should begin with the completion of an athlete’s questionnaire. This questionnaire provides a coach with valuable insights that serve to identify characteristics unique to the athlete. The questionnaire should include sections that explore relevant statistical, personal, medical, and volitional data. By understanding the unique circumstances surrounding the person, not just the performer, we are able to match appropriate training methods to individual needs

STATISTICAL DATA
The survey process should begin with questions such as address, telephone number, date-of-birth, grade-point average, and college-board scores. Class schedules should also be noted. It is also helpful to list shoe and uniform sizes in this section. With a master list of this information on hand, emergency equipment problems can be minimized. Many more questions of this type can be included in this area of the questionnaire.
One of the most important inquires from this portion of the questionnaire is the determination of training age. Training age is a measurement of athletic experience expressed in years. It is determined by totaling the amount of time spent in a structured athletic program. The athlete who participates in sport for only three months per year, over a total of four seasons has a training age of “one.” Though a four-year veteran, a training age of one-year suggests that this athlete is still in athletic infancy. This important characteristic should greatly influence the training loads prescribed for any performer.

PERSONAL DATA
This section of the questionnaire examines the home environment, family influences, personal achievements, and employment status of the individual. It should be determined if one or both parents are in the home, or if the athlete lives with other relatives. How many brothers and sisters does the athlete have and what are their ages? Are parents or siblings athletes? Does the athlete have a nickname? Is the athlete a member of any clubs or organizations? Does the athlete have a part-time job? We should also explore other areas of the athlete’s life that may have provided opportunities for success. Has the athlete earned any awards in academics, art, and drama or in other sports? This data serves to identify the intangible qualities the athlete may possess as demonstrated in other activities. Demonstrated qualities such as determination, dedication, persistence, loyalty, and other virtues can transfer to any athletic endeavor.

MEDICAL DATA
A medical history should be included in this questionnaire. The family doctor’s name, date of last examination, any prescribed medications and allergies should be listed. Any injuries, especially those suffered in athletics, should be documented with their diagnosis, therapy and current status.

VOLITIONAL DATA
Volition is defined as “the act or power of the will.” In this section we should attempt to discover the motivation, tolerance and objectives of the athlete. is best to begin by simply asking, “ Why are you here?” The wide range of responses to this question may surprise you. Some athletes participate because they are looking to earn a scholarship, while others are attracted to being part of a team. Others may be compelled to participate by pressure from their parents and friends. They may have joined the team simply out of love for the sport or to improve their fitness. And of course, there are always those who are not really sure why they signed up! Perhaps they stumbled in your door by chance or out of curiosity.
The novice athlete who is unconvinced of their athletic potential will demand a special rapport with the coach. The athletic infancy of a novice will require not only reduced training loads, but special encouragement as well. The experienced athlete with state-meet aspirations will likely have a very different relationship with the coach, as well as significantly more challenging workloads.

FIELD TESTS
The test course will consist of an acceleration zone and a 30-meter timing zone. Novice athletes should use a 15-meter acceleration zone, while more accomplished athletes can use a fly zone of 20 to 25 meters.
15 - 20m 30 m
- - - - - - - - - - - ————————
ACCELERATION ZONE TIMING ZONE

Evaluating Maximum Velocity
The 30-meter fly test evaluates the maximum velocity capacity of the athlete. The athlete is instructed to sprint through the acceleration zone and the 30-meter action zone with maximum effort. He or she is timed, however, only from the start of the 30-meter test zone to its finish. When the distance run (30-meters) is divided by the time recorded, the answer reveals the maximum velocity of the athlete in terms of meters per second (the number of meters traveled in one second, while sprintingat full speed). If the split time were 3.0 seconds in the fly 30 test, the maximum velocity of the performer would be 10.0 meters per second. To date, the world’s fastest men and women have posted top marks of 12- and 10-meters per second respectively. Developing athletes will register values close to 10 meters per second for boys and 8 meters per second for girls.

Evaluating Acceleration
Acceleration skills can be evaluated by conducting a standing 30-meter dash. Athletes should be instructed to sprint from the start of the 30-meter timing zone through the finish beginning from an upright, standing start. The watch should be started from the instant the rear foot leaves the ground, and stopped when the torso crosses the end of the timing zone. Only experienced athletes of at least college-level should use a crouched start for this test.
The acceleration skills of an athlete can be judged by reviewing the differences in performance between the 30-meter fly test and the standing 30-meter test. Subtracting the fly 30m time from the standing 30m time reveals the acceleration differential. Accomplished sprinters will register a 1.0 second differential, while a developing athlete’s mark will fall into the 1.4 to 1.6 range. Lowering this differential is the best evidence of improvement in the acceleration phase.

Evaluating Sprint Endurance
Sprint endurance can be determined by adding a second 30-meters to the existing timing zone for a 60-meter fly test. Athletes should be instructed to sprint through the acceleration zone and both 30-meter timing zones. The test effort should include a split time at 30-meters and a finish time at 60-meters. Sprint endurance can be evaluated by comparing the performance times recorded in both 30-meter test zones. If the first 30-meters was covered in 3.0 seconds, the second zone should measure no more than 3.09 seconds for the elite sprinter (a 3% variance). Developing sprinters may show a differential between the 30-meter splits of 5 – 6%.

Evaluating Speed Endurance
The objective here is to measure the athlete’s resistance to fatigue with a block-start or standing 150-meter test run. From the recorded time, we can calculate the mean or average velocity run over this distance by dividing 150 meters by the finish time. If the athlete posts a mark of 20 seconds, the mean velocity is 7.5 meters per second. A primary training objective should be to narrow the gap between a sprinter’s mean and maximum. If the athlete has shown a maximum velocity of 10-meters-per-second and a speed endurance mean velocity of 7.5 meters per second, we can conclude that the athlete’s current speed endurance capacity is 75% of maximum speed. We will want to increase this percentage through training.
Evaluating Special Endurance
Special endurance can be evaluated by conducting a timed 300-meter run. Special endurance reflects an important metabolic capacity of the sprinter. Once again, the mean velocity is calculated. For example, if the athlete’s time was 40 seconds, the mean velocity for special endurance is 7.5 meters per second. If the maximum velocity of the athlete measured 10 meters per second, we can conclude that the special endurance of the individual is 75%. Again, we will want to increase this value through training.

MEASURING AEROBIC CAPACITY
Aerobic or work capacity refers to the amount of work an athlete is capable of producing. We can also identify the capability of expanding a sprinter’s range of performance to include middle-distance events with this test.
The simplest aerobic capacity test is a 12-minute run recording the total distance covered during that time. Developing athletes will typically travel 2200 to 2600 meters (5.5 to 6.5 laps of a 400m track) in 12-minutes. Accomplished sprinters will cover 2800 to 3200 meters (7-8 laps) in this test. This test is most appropriate, however, for the developing athlete. The results of this run should also be expressed in terms of the mean velocity achieved. For example, if the athlete covers a distance of 2400 meters during a 12-minute run, endurance capacity is : 2400 meters divided by 720 seconds (12-minutes) = 3.33 meters per second.
This mean or average velocity should then be used to evaluate current endurance capacity and to measure improvements over time.

Measuring Elastic Strength
The vertical-jump test measures elastic strength. From a squat jump, the athlete extends vertically covering as great a vertical distance as possible. The jump height can be calculated by attaching a measuring tape to a wall. The athlete should begin with arms outstretched overhead and noting the starting point. When the jump is executed, total distance covered above the starting mark is recorded. It is essential that both arms reach upward simultaneously to assure consistent results. A developing female athlete will record marks between 46cm and 56cm, while her elite counterpart will tally 61cm to 71cm. The developing male will demonstrate 61cm to 66cm, while the elite male will post a jump of
71cm to 82cm.

Evaluating Elastic Power
The 5-stride bounding test will provide insights into an athlete’s power capacity. The athlete should be instructed to stand with feet aligned, and starting off both feet, to bound forward for a total of 5-strides. The object is to span as great a distance as possible. The best bounders will show high levels of negative foot speed, stable joint systems, and little front/side distance at landing.
Expect developing women athletes to show marks of 11.5 meters to 12.8 meters, while elite women will show a range of 12.8 meters to 14 meters. Developing men will bound between 12 meters and 13.5 meters, while elite men will post bounds of 14 meters to 15 meters.

COACHING THE MECHANICS OF SPRINTING
The process of achieving faster sprint times begins with training to improve the sprinting mechanics of the athlete. This can be achieved through carefully choreographed drills. With repeated rehearsal, these sprint drills will create permanent patterns of movement which work like an auto-pilot for the sprinter.

DORSIFLEXION
A key principal to understand is the importance of dorsiflexing the foot (pulling the toe-up) while sprinting. A visible technique in all great sprinters, this important joint position is exhibited throughout proper mechanics. It can be demonstrated with this exercise: Raise your arm as if to flex your biceps, but keep the muscle relaxed. Place your free hand on its bicep. Now turn your wrist-in (the “walk-like-an-Egyptian” pose). What happens to the muscle? It seems to disappear. Now turn your wrist back to its original position. The biceps comes back to life! This exercise illustrates how joint positions determine muscle recruitment. If your wrist is in the wrong position, your biceps simply turns off and is useless to you.
In the same way, ankle positions determine which muscles are active during running. When the ankle is dorsiflexed so that the toes are pulled up, you can feel the gastrocnemius (calf ) muscle go to work. When functioning, it allows the athlete to pull their leg through the recovery phase (heel-to-butt) in less time during the running stride. The result is less time wasted in the air. Therefore, a key mechanical principle in running at any speed is keeping the toe up! When that same leg reaches to land on the next stride, once again the ankle should be dorsiflexed. With the toe-up at landing, the ankle works like a spring-board and muscle elasticity moves the athlete off the ground in less time. Less time on the ground, or in the air, gets every runner to the finish line faster.

DRILLS FOR SPEED
Ankling Drill
Objectives: To limit time spent on the ground and to develop an elastic response in the ankle joint. Beginning with a walk, with each small step taken, step no higher than the top of the opposite ankle. Emphasize the ankles remaining dorsiflexed throughout the drill. The look of the drill is that of a quick-shuffle action. As tempo increases, an elastic response in the ankle increases. Arms and legs should be active with the elbows loosely positioned at 90 degrees. In ankling, horizontal speed is insignificant. The focus is on limiting the time spent on the ground. Athletes should be instructed to listen to their steps and try not to make a scuffing noise with their shoes. Verbal Cues: “toes up,” “quick feet,” “hot ground,” “fast shuffle,” spring-board action.”

Butt-Kick Drill
Objective: To reduce the time necessary for recovering the foot from the ground to the buttocks by using the gastrocnemius muscle to fold the calf tightly against the hamstrings.
The technical focus of the butt-kick drill is the ankle, which should be dorsiflexed throughout the exercise. Beginning with a jog, proper ankle position should be maintained as the heels quickly fold-up to the buttocks. A contact “slap” should be audible. When the drill is first introduced, the thigh can be close to perpendicular when the foot contacts the buttock. As skill increases, however, the knee should rise and the thigh will approach a parallel position as each heel slaps the buttock. Once again, avoiding scuffing the running surface is key. This drill is an excellent exercise to simultaneously improve a sprinter’s arm-action by driving the elbows back quickly in sync with the legs. Verbal Cues: “elbows back,” “toes up,” “hands like hammers.”

A” Drills
Objective: To improve efficiency of movement and to establish the best mechanical position in which to begin the next stride. The names we tend to give exercises can distract us from proper execution. High-knee Drills” are perhaps the best example. Getting the knee high isn’t sufficient. Therefore, the “A” series avoids any confusion with the use of a generic name. In the “A” Drill, the toe, heel, and knees should come up simultaneously. The calf should be kept tightly folded against the hamstrings and thigh parallel to the ground as the foot steps-over the opposite knee. To complete the stride cycle, the thigh is then driven back down to and then past the perpendicular position at landing and the foot
pulls the ground back underneath the hips. The “A” Drill should begin with a march. As skill increases, the march can transition into a skip and then a run. The shoulders should remain above the hips throughout the A drill, and the athlete should avoid tilting the pelvis back like a drum major to make it easier to lift the knees.

Verbal Cues: “toe up-heel up-knee up”, “step-over the opposite knee”.

Fast Claw Drill
Objective: To re-pattern neuro-muscular movements and create improved vertical leg speed.
This exercise is performed one leg at a time. It begins with the athlete standing erect with the thigh of the active leg blocked in a parallel position, the toe should be up and ankle cocked, and the heel of the support leg off the ground. To begin, the thigh is driven down to a perpendicular position as fast as possible, and the foot recovered back up as quickly as possible. The knee joint remains loose allowing the lower leg to swing out naturally. The cyclical action used in previous drills applies here. The Fast Claw Drill can be performed continuously, for adesignated number of repetitions or on command.

B” Drills
Objective: To reduce breaking forces at ground contact by generating high levels of negative (backward) foot speed. (Can also be used to simulate the sensation of hurdle clearance.)
The single characteristic which most distinguishes developing sprinters from elite sprinters is the ability to produce negative foot speed. This exercise allows athletes to experience the sensation of pulling the running surface back underneath them. When this negative or backward foot speed is at least equal to the velocity of the hips traveling forward, little deceleration occurs as the foot lands.
The “B” Drill begins with the same action as the “A” series with the toe-up, heel-up, knee-up, and the foot stepping over the opposite knee. When the thigh blocks in a parallel position, it should be quickly re-accelerated back to a support stance. In the “A” series of drills, the speed of the leg through the stride cycle is the same. In the “B” Drill, the speed of thigh driving back toward the ground is noticeably faster than the recovery action and the front-side movement dominates the exercise. Contrary to popular opinion, it is not necessary for the sprinter to try to kick-out the lower leg in front of him/her. This action will occur naturally as a result of the quick change of direction in the thigh position. Unlike the “A” series, “B” Drills should begin with a full skip and progress to the march that requires high levels of strength, flexibility and skill. The full series of “B” Drills includes a full skip with both legs active, a single- leg “B” skip, a “B” run, and a “B” march.
Verbal Cues: “step over,” “drive the thigh,” “grab back.”

Straight-Leg Shuffle
Objectives: To develop high levels of negative foot-speed and increase specific strength in the hamstrings and glutes. in this exercise, athletes should be told to forget they have a knee joint. Keeping the toes up, ankles dorsiflexed and shoulders positioned in front of the hips, the leg swings straight out, then quickly changes direction and drives back into the running surface. Athletes should feel the hips projected forward as they attempt to pull the ground back underneath them. Once the basic movement is mastered, the straight-leg shuffle can evolve into a straight-leg bounding action by applying greater negative force at each landing. Proper running posture should always be maintained.
Verbal Cues: “tear back the track,” “pop the hips through.”

COACHING THE MAXIMUM VELOCITY PHASE
Seeking improvements in the maximum velocity of the athlete should be our first training focus with sprinters. Gains in this performance phase are the foundation of success in sprinting. Though the duration of this segment of a sprint race is often only 2-4 seconds, its impact on the finishing result is profound. Our training objective is to break through the dynamic stereotypes which limit performance and create new, improved motor patterns in the athlete. These new motor patterns will result in improved efficiency of movement, mechanical gains in force output, and a reduction in time spent on the ground and in the air. In strength training, we understand that as an athlete’s maximum capacity increases, every other degree of strength will benefit as well. Just as we design training in the weight-room based on a percentage of an athlete’s maximum strength capacity, so should we address speed development. With improvements in our sprinters’ maximum velocity, measurable benefits will filter down to all their other movement skills. Since the maximum speed capacity of an athlete relies less on strength and power than other racing phases do, it makes sense to begin this training early in the season when strength is lacking. This begins with the most important drills the sprinter will ever perform.

FAST-LEG DRILLS
Objectives: To develop vertical leg-speed and neuromuscular coordination. This series is designed to improve the maximum speed of the athlete without any emphasis on horizontal movement. Here our focus is on improving the vertical component of sprinting.

Four-Step Fast-Leg Drill
Horizontal speed is unimportant so this drill should begin with a slow jog, recovering one leg only, up as quickly as possible and back down again four times as quickly as possible. As always, emphasize “toe-up, heel-up, knee-up, step-over the opposite knee.” The sprinter should feel as if he is leaving the support leg behind, never stepping forward with it. This drill is performed with sets of four repetitions separated with a few jogging strides using one active leg over a distance of 30-meters, and returning to the starting point drilling the other leg. It can progress to distances of 50 to 70 meters.

Alternate Fast-Leg Drill
Once both the left and right side fast-leg drills are mastered individually, you can enhance the skill with an alternate fast-leg routine by taking two steps and fast-leg the other side. As skill increases, the jog progresses into a moderate run. The legs should function autonomously from the upper body. No jerking of the torso should occur during the fast-leg action.

Continuous Fast-Leg Drill
Instruct athletes to imagine one leg is dragging a weight from the ankle. (The sensation is not unlike wearing a ball-and-chain as some prisoners once did.) The drill starts with a walk, with the support leg lagging behind, and fast-leg action on the other side on every stride. Balance is maintained by keeping the arms and legs synchronized.

Command Fast-Leg Drill
In this drill athletes move in a slow jog down the track. The coach shouts the number of fast- legs to be performed in a consecutive effort. The athlete performs the quota, and then returns to a jog waiting for the next number of fast-legs to be performed. One, two or three reps are appropriate.
The side on which the fast leg is performed can also be designated, along with the number of reps desired, e.g. “2 left... 1 right... 3 right.”

Complex Fast-Leg Drills
You can further enhance fast-leg skills by using the routine with other drills like ankling, butt- kicks, and straight-leg bounding.

TRAINING AT SPEED
Speed-work,” as commonly defined, does not fit into the Speed Dynamics® philosophy. Traditional speed-work sessions with bouts of 10-to-30 second runs do not replicate the actual short duration of maximum velocity sprinting. Since the neuromuscular system can only fire at maximum levels for only 2 to 3 seconds at a time, speed work for sprinters must reflect this reality.

Fly-In Sprints
Fly-in sprinting is an excellent training tool to develop maximum speed. The training course should consist of a “fly” or acceleration zone of 15-25 meters, and an “action zone” of 20 to 40 meters marked with traffic cones or hurdles on either side of the dedicated lane(s). The objective of these fly-in sprints is to capture the maximum velocity phase of the sprinter’s race so that specific improvements can be made. The speed of the run increases gradually through the fly zone as the action zone is approached. The action zone represents the maximum velocity phase of a sprint race. Transit time through the action zone should never be more than 2 to 4 seconds.
The length of the action-zone should be based on the maximum velocity capacity of the athlete as measured in the fly 30m test. The developing sprinter will typically begin training with an action-zone of 20-meters.
More accomplished sprinters can utilize a 30-meter action-zone. In time, the length of these respective zones can increase to 30-meters for the developing sprinter and 40-meters for the accomplished sprinter.
During acceleration, the sprinter should breath normally, but when the action zone is reached, the athlete should hold his breath for the first 4 to 6 strides and sprint as fast as they can through the end of the action zone. The coach should always cue the specific mechanics desired during maximum velocity sprinting. Since the time available to cue the athlete and prompt a response is short, cues should be composed of no more than two words or syllables. “Toe up,” “step over,” “grab back” are best.
. Breath Control
One of the unusual nuances of this training is the breath control previously described. Research has shown that holding one’s breath actually increases the ability to apply force. This action, which has been
traced back to the “fight or flight reflex” of our ancient ancestors, causes physiological changes advantageous to explosive movement to take place. Evidence suggests that instinctively, we have always been aware of this advantage. From the attempt to pry loose the stubborn lid on a jar, to the Herculean effort of a maximum lift in the weight room, holding one’s breath makes the task easier to perform by increasing thoracic and interabdominal pressure which acts as an “air-splint” for the spine. Stabilization of the spine improves the ability to apply force. Furthermore, research shows that breath control increases intra-cranial blood pressure, which leads to an improved ability to recruit motor units. In short, the ability to apply big forces to the track improves when holding the breath. However, breath control is useful only if it can be implemented practically. The use of breath control in fly-in sprints and the Ins-and-Outs training to be discussed later, will lay the foundation for a new race model over the course of the season. This model will allow new sprinting skills developed in training to be transferred to competitive sprinting. Another advantage of using breath control techniques is the improved awareness it prompts in the sprinter. Holding one’s breath is a dramatic cue that signals the athlete that a special focus is now required. It also creates a definite sense of urgency about reaching the normal breathing check-point. Coaches will find their sprinters will no longer coast through a sprint session without the attention to detail required for success in these events.

Sets, Reps & Recovery Notes for Maximum Speed Training
Fly-in sprints should be introduced with a single set of three repetitions. As training continues, this routine can progress towards a total of three sets with three repetitions in each set. For the developing sprinter, total volume should not exceed 500-meters per week. For the accomplished sprinter, 800-900 meters per week is appropriate. Recovery times for metabolic training have long been the subject of debate. For speed-work, however, full recovery is appropriate regardless of the period of season. The operative word here is speed. When speed-development is the goal, full recovery is required between bouts of running. Energy system training is an altogether different matter. While the opposite would seem to be true, the developing sprinter generally requires less recovery time between repetitions and sets since a young person’s neurological system is more pliable than an adult. This is because novice athletes have not developed the ability to fully stress their nervous systems as more accomplished athletes have. Another consideration for adjustments in recovery time for the developing athlete is the short attention span typical of this group. Often the novice cannot maintain training focus through long recovery phases. In this instance, shorter recoveries may be wise when all is considered.
Two-minutes recovery between reps, and ten minutes between sets, is a good starting point for developing athletes. At the elite level, as much as ten-minutes between reps and twenty- to-thirty-minutes between sets may be appropriate. Speed development sessions can be utilized two-to-three times per week. Gains in the performance of the neuromuscular system, however, are contingent on sufficient time being allotted for recuperation. Coaches should always allow 40 to 72 hours of recovery time between maximum speed-training sessions, depending on their duration and the training age of the athlete.
Coaches can measure the readiness of the athlete’s neuro-muscular system with a simple diagnostic test. Just as the endurance athlete tests readiness by monitoring heart-rate data, the sprinter can judge the status of the neurological system with the use of a stopwatch. This is done by the athlete starting the watch and immediately clicking-off as many splits as possible in ten-seconds and noting the range of split-times registered and their consistency. Typically, the athlete will produce split times of .16 to .20 when rested. If the neurological system is fatigued, the split-times increase and become more inconsistent. If sufficient recovery of the athlete is in doubt, prior to a speed-training session this stop- watch test can offer valuable feedback. If the performer shows a marked increase in the split-times registered from previous trials, it may be wise to postpone the speed-work session until the next day.

ACCELERATION
Once the development of the maximum velocity capacity has begun, the next sprint-training focus should be improving acceleration. The objective of the acceleration phase is to reach maximum velocity as quickly and efficiently as possible. The acceleration phase, from a mechanical point of view, must be broken down into a “pure acceleration phase” and a transition phase.” Pure acceleration begins after the first two steps out of the blocks, and blends into the transition phase after the tenth or twelfth step. The duration of the transition phase is typically 6 to 8 strides.
CHARACTERISTICS
The primary characteristics of the pure acceleration phase are the relationship between the hip and foot of the sprinter. Unlike sprinting at maximum velocity, accelerating requires the feet of the sprinter to hit the track behind the hips in the earliest strides. With each additional step, the sprinter assumes a more upright posture. The distance between the center of mass and base of support continues to lessen until the feet land directly under the hips. During acceleration, the joint angles at the hip and knee are much sharper prior to ground contact when compared to maximum velocity. The direction of forces applied is more horizontal than vertical in this racing phase. Correct acceleration mechanics require maximum acceleration of the thigh over its full range of motion, meaning the knee comes up fully and quickly. Rather than the cyclical action of top-speed sprinting, the shins move with a “back and forth” piston-like action in acceleration.
The knee of the sprinter remains in front of the foot, both in the recovery and drive phases and the feet remain close to the ground. The corresponding angles of the shin and torso should be the same with respect to the ground.
The ankle is always cocked in anticipation of ground contact being made with great force.
Acceleration and maximum velocity not only differ in the direction of the forces applied to the track, but also in the origin of those forces produced. In acceleration, much of the force is generated from muscle contraction rather than elastic response. This is true in all events requiring acceleration.
Stride-length in the initial two steps of block-clearance and the ensuing eight to ten steps of pure acceleration increases at an amazingly regular rate. A range of increase of 10 to 15 centimeters is not uncommon. A slight decrease in stride-length is found near the end of the phase. This increment is directly related to the sprinter’s leg-length and strength and power to body-weight ratios. Surprisingly, stride-frequency is extremely high for the elite sprinter during the acceleration phase. Here too, we see an incremental increase in the stride-rate of the athlete. Only in acceleration do we see striderate and stride-frequency increase this way.

IMPROVING ACCELERATION
As coaches, we can improve acceleration skills of our sprinters in three ways:
1. Give task-specific cues. Offering concise instructions to the athlete will help to actualize the precise body positions and mechanics sought in this racing phase.
2. Increase the general and specific strength and power capacities of the athlete. Many different means of training can be utilized to accomplish this objective.
3. Re-program the neuro-muscular system.We can choreograph the precise movements of acceleration through specific training and regular rehearsal.
Task-Specific Cues
Significant study and preparation are required in all areas of a coach’s responsibilities. Yet, the coaching capacity that may influence the sprinter and their performance the most is usually the one allotted the least amount of thought or preparation. The way in which desired results are communicated to the athlete is perhaps the most important single component in the coach- athlete relationship.
The words coaches speak create specific visual images. It is these images that will prompt action by the athlete. Whatever mental picture the sprinter is provided with, whether it is desirable or not, will be acted upon. Since the mind follows the direction of its current thought, the coach must be exact and precise with cues given to a sprinter. In training and competition, the athlete should be reminded of the specific motor responses needed. This reminder is not new information. Instead, the cue will call up in the mind of the athlete the mental stimulus to be acted upon. Since each racing phase has its own inherently unique characteristics and demands, the instructions offered to the sprinter must reflect this diversity. Each racing phase requires its own set of specialized cues.
In contrast to the vague clichés common in coaching jargon, the cues given to sprinters must describe a specific action which paints a universally recognized picture. The frequently used cue for acceleration of stay low” is an example of the misdirection many coaches inadvertently offer to athletes. This cue provides the sprinter with a distorted mental image of the body position required in acceleration. Bending at the torso as if ducking under a tree branch is a common but undesirable body position in sprinters. No doubt the “stay-low” cue has much to do with it. Instead, we want the sprinter to lift the chest up so that a power line is created from the ankle of the support leg through the torso and head. In this way the body lines up at about 45 degrees with respect to the track. More appropriate cues would include “stab back” or “push the track behind you.” These descriptions relate to the direction of forces and foot placement required for acceleration. The following recommended drill sequences for acceleration also serve to emphasize the unique characteristics of this racing phase. The sprint coach is continually challenged to develop new cues to create the responses he seeks. He can signal the high frequency desired in acceleration with cues like “hot ground,” “quick feet,” or even generic sounds that emulate the rhythm and tempo of the reoccurring foot strikes. Hand claps with an ever increasing rhythm, for instance, make that point. When a sprinter describes how their race is to be run, the words they choose can be very telling. If their account of the actions of the race is general and nondescript, we can expect this to be reflected in their technical execution on the track. Athletes should be regularly questioned to determine the state of their technical understanding of their events. If language seems to be failing either the coach or the athlete, pencil and paper can help. When uncertainty exists regarding the sprinter’s imagery of racing techniques, ask him to draw stick-figure examples of the desired movements and body positions throughout the various sprint-racing phases. This transfer of the athlete’s mental image of technical performance characteristics to paper will give a coach a clear view into the mind’s eye of that sprinter.
Another method to clarify an athlete’s grasp of specific technical cues and concepts is to carefully observe how he/she assists younger, inexperienced sprinters. A person can only teach what he/she knows
him/herself. So when one athlete instructs another, his/her expertise is revealed. Observing the athlete as a teacher is an acid test of his/her technical awareness.

TRAINING FOR GENERAL & SPECIFIC STRENGTH
The ability to accelerate will improve in direct proportion to gains in strength. We can increase the general strength and power capacity of the sprinter with many different means of resistance training. All of these methods are intended to increase the amount of force the athlete can apply and the integrity of the pillar and the joint systems, and to limit the time spent on the ground.
Simple jogging is the place to begin. Even a slow jog requires the performer to move against the resistance of gravity. As a foundation of general conditioning is developed with easy running, we can increase the demand on the athlete by changing the grade of the running surface.
Running up a hill or incline requires the athlete to lift the recovered leg through a greater range of motion than on a flat surface. The athlete must therefore exert a force against the ground sufficient to lift the center of mass somewhat higher than normal. The result is an increase in strength and power where the sprinter needs it most.
Multi-throws training is another excellent means to improve general and specific strength and power values. “Multi-throws” are exercises which combine movements through various ranges of motion followed by throwing an implement for distance using shots and medicine balls. One example of a multi-throw routine is the “between the legs forward throw.”Holding the implement in both hands, the athlete bends forward and swings it back between the legs, then quickly changing directions, swings it up underhanded for as great a forward distance as possible. In this type of exercise, the body mass of the athlete increases by the weight of the implement held. As that body moves, stressors to the muscular system increase. Finally, when the ball is launched, a great force must be applied into the ground. The athlete also must extend into the same body position desired in acceleration. This combination of increased loading, greater force application, and desirable body position are all obvious benefits for acceleration training.
Sprinting with a weighted vest or weighted pants is another proven method of enhancing strength and power. Once again, we increase the load to the athlete’s sprint systems by adding weight. By increasing the mass of the sprinter, we effectively expand the stimulus to the stretch shortening phenomena. The result is an improvement in general and specific strength and power and a reduction in time spent on the ground.

CHOREOGRAPHING THE MOVEMENTS OF ACCELERATION
As we work to improve the strength and power of our sprinters, we must simultaneously develop the specific skills of the acceleration phase. These skills are best introduced through the following drills and exercises. Each is 0designed to teach proper body-position and the desired direction of forces applied to the track. Repeated rehearsal of these routines will refine the motor pattern of the athlete to adapt to the unique demands of this racing phase.

A LEARNING PROGRESSION FOR DEVELOPING ACCELERATION SKILLS
Acceleration March Drill
Objective: To teach the desired body position and piston-like movement of the legs. Start with the athlete standing approximately one-and-one-half meters from a wall or other stationary object. With the feet fixed in place, have the athlete lean against the wall placing the hands flat against it. The body position achieved should now be approximately 45-degrees with respect to the ground.
On your command, the athlete begins to march by recovering one leg up with the ankle dorsiflexed and knee rising high to a point above waist level. Then the other leg is similarly recovered while the first is returned to exactly the same position on the floor. This march should continue for a 10-second interval. The pillar should remain in line with the support leg throughout the exercise. The movement of the legs is not cyclical as is the case in maximum speed running. Look for a back-and-forth leg action with the knees remaining in front of and above the ankle at all times. While this exercise will test pillar strength, it is intended most to familiarize the athlete with the critically important body position unique to acceleration.

Wall Sprints:
Objectives: 1) To mimic the sprinting action found in acceleration without fighting the forces of gravity; 2) To improve stride frequency and refine the direction of forces applied to the track. Begin by assuming the same position as in the acceleration march drill. The athlete recovers one leg up into the ready position. This leg should be the same one that will be positioned in the front pedal of the starting blocks. This “ready” stance requires that the ankle on the recovered leg is dorsiflexed, knee is up above waist height, and torso is in line with the support leg.
The coach then announces in advance how many total steps are to be taken in succession. It is recommended to begin with sets of 3-steps. Holding his/her breath, the athlete sprints through 3 steps, exhales and holds his/her position. The instruction for the next set comes right away.
Doing three continuous sets is standard. Once mastery is achieved, 5-steps then 7-steps, etc. can be utilized in each set.

Continuous Wall Sprints:
Objective: To promote pillar strength, stride rate, and energy system fitness while replicating the movements of acceleration. Here again, the athlete assumes the same ready position as previously described. On the coach’s command, the athlete begins to sprint continuously. The focus is on achieving the highest possible frequency while moving the legs through a complete range of motion. The duration
of exercise begins with 5-second intervals. As competency increases, the time should be increased up to 10-seconds or more.

PARTNER DRILLS
Hip Hold:
Objective: To support the athlete so that desired body position and movements of acceleration can be rehearsed at sprint speeds. A spotter stands behind and places his/her hands on the hips of his/her partner who leans forward with a flat back and firm abs. The spotter steadies his/her body position. On the coach’s command, the athlete begins to pump his/her legs and arms in the desired piston-like motion sought in acceleration. His/her body position is maintained due to the support of the spotter.
After 4-to-10 steps, the athlete is released and continues to sprint through a designated distance of 30-meters. Regardless of the number of steps taken, when the spotter can no longer feel the weight of his/her partner, he/she lets him/her go. If he/she cannot feel the weight of his/her partner, we know the sprinter has lost the desired body position.

Face to Face:
Objectives: To increase forces applied to the track and identify when desired body position is compromised. In this exercise, the spotter faces his/her partner and supports forward body-lean by placing his/her hands on the shoulders and accepting his/her partner’s weight. On cue, the athlete begins to sprint with proper acceleration mechanics. Arm action should be encouraged. Total distance is 30-meters. When the spotter can no longer feel the weight of the athlete, let go and step aside. The athlete will likely revert back to old bad habits and allow the legs to become perpendicular at some point in the exercise.

Face and Chase:
Objectives: To develop transition skills. The athlete begins as in the previous drill. After 2-to-6 seconds of action, the spotter turns away from the performer and sprints to the finish 30-meters away. The athlete now becomes the pursuer. The goal is to catch the spotter before the finish-line. The spotter of course will attempt to out-sprint his/her partner.
This exercise becomes a game while addressing several crucial training objectives. When the spotter turns and runs from the athlete, the resistance which his partner worked against ends, as does the artificial support of his body position. Neurologically, the sprint systems respond to the contrasting demands of early resistance against the spotter and then the full final-sprint without the impedance. Add to the mix the competition factor between the partners, and the result is an effective training session for both sprinters.

Face, Chase and Race:
Objectives: To improve transition skills, pillar strength, and energy system fitness.

This final progression in partner drills adds another element to the Face & Chase routine. Again, designate a start- and finish-line 30-40 meters apart. Begin the exercise as before. The spotter supports the athlete with his/her hands on his/her shoulders. The partner drives out against the resistance aggressively. Two to six seconds after the exercise begins, the spotter turns away from the partner and attempts to sprint across the finish without being caught from behind. The new element to this exercise is that when the spotter is tagged by his/her partner’s hand, both athletes stop, turn 180-degrees and race back to the starting line. If the spotter is not caught before reaching the finish, they both turn around after the spotter reaches the finish line and sprint back to the start line. Many benefits can be derived from this drill. First, the competitive aspect of the drill improves its intensity of performance. Second, the sprint systems respond to the contrasting demands of resistance, braking, change of direction, and re-acceleration. Finally, the drill shows that serious training can be achieved in a game-like setting and that hard work and fun can go together.

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