Speed abilities

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Training speed abilitiesThere are different manifestation of speed in training, e.g. the speed of a sprinter in a 100-meter run, reached javelin release speed, maximum speed of the starting run of the athlete in a long-distance jump, the speed of changing position of the middle player from the middle part of the net into side area, break-free with the ball in basketball etc. Sports performance is conditioned by performing a given movement with maximum speed possible. External manifestation of the resulting speed of both cyclic movement and single-speed movement are always related to as fast carrying out of the movement as possible along defined specific track through muscle contraction. The specificity of movement is given by specific skill in the sports discipline. Manifestations of speed in sports are always characteristic in their maximum intensity. Acyclic movement (throws, casts) can be performed against slight resistance (up to 20 % 1RM). Cyclic movement (sprint) is usually performed without resistance without any significant change is direction. During cyclic movement, a significant change in direction can occur accompanied with decrease and subsequent increase in speed and movement frequency (movement of player with the ball in handball). In this case, it is specific manifestation of speed which is called agility. As far as the duration of the performance of specific motor activity is concerned, it is speed up to 15 seconds (duration exceeding 15 seconds is speed endurance). An independent part of speed abilities is represented by the scope of reaction speed. Reaction speed is manifested by speed as a reaction to a given stimulus (e.g. reaction to start-up shot in 100-meter sprint) and it is understood as time lasting from stimulus to the start of motor activity.

Speed can generally be defined as an ability to reach high speed and frequency of cyclic, single-speed (acyclic) or combined movement through muscle contraction.

Basic areas of speed abilities

Basic areas of speed abilities

 

The most important areas of speed abilities from the point of view of sports training are represented in Figure.

Significant areas of the complex of speed abilities

Significant areas of the complex of speed abilities

Cyclic speed (locomotion speed) is understood as an ability to reach high frequency of cyclic movement through muscle contraction without any significant resistance in duration unitl 15 seconds.

Single speed (acyclic speed) represents an ability to reach maximum speed of the movement without resistance or against slight resistance through muscle contraction.

Agility is an ability to change direction of movement quickly; it is accompanied by sudden decrease and subsequent increase in acceleration and speed of the movement.

Speed endurance is understood as an ability to maintain high speed of movement for a time period longer than 15 s or an ability to repeatedly produce high speed of movement with minimum resting period between individual repetitions.

Reaction speed is an ability to react to a given stimulus as fast as possible.

Development of speed is closely related to strength development; mainly to development of fast speed and reactive strength. To be able to perform a given motor task (motor ability), the athlete must apply strength as fast as possible. Strength is understood as a product of mass and acceleration. Strength which is necessary for performing movement is produced by skeletal muscle. Speed performed in sports is affected by three basic parameters:

  • Strength impulse which is given by an ability to apply as big force as possible in restrected time given by a specific sports event. Strength impulse is then equal to the change of momentum of the athlete or tools.
  • Net power output which is understood as the result of the product of applied force and speed while performing a specific movement within a given sports skill.
  • Stretch shortening cycle (SSC) which represents a combination of eccentric and subsequent concentric muscle contraction.

Maximum value of strength impulse is importance in situations where it is necessary to apply a big amount of force in short time. A good example of this is sprint during which support and flight phases of the left and right lower limbs alternate regularly. During support phase, the runnes has only 0.1-0.2 seconds to take off from the surface do another flight phase. Within such short time, the athlete must applie as high rate of force development (RFD) as possible at take-off; whereas the maximum growth in force occurs only at times between 0.6 and 0.8 s. Te speed of force development is presented in Figure. Training of maximum rate of force development within limited time interval in specific sports skills is an important part of training performing speed.

Rate of force development

Rate of force development

Net power output plays an important role in training performing speed. For instance, in javelin throw, the length of throw depends on two basic parameters: release angle and release speed. Choosing release angle is a matter of thechnique of this skill. Reached release speed is related to reached net power output. The athlete must be able to reach maximum net power output with mass defined in advance (in this case it is the weight of the javelin). Net power output results from the relationship of velocity of movement and force which causes the movement. The relationship between velocity of movement and the acting force is indirect. Maximal force is reached at a low velocity and on the other hand, at maximum velocity, the acting force is small. In both of these extreme situations, net power output is low. Maximal net power output is a compromise between velocity of movement and the amount of acting force. The athlete must act on the javelin with optimum force which ranges, as described in theory, around 40% of maximal force and around 30% of maximal velocity. The above relationship is presented in Figure. Another example can be bench press exercise. It has been proved that for the training method of dynamic effort, load within the range of 30-50 % 1RM is most appropriate for professional football players. With such load, the players reached maximal net output and therefore the load is most appropriate from the point of view of traning stimulus and subsequent adaptations.

 Relationship between applied force and the velocity of movement

Relationship between applied force and the velocity of movement

The principle of training maximal net power output is an important part of training performing speed. In sports disciplines such as sprint, the athlete must reach maximum performance with the weight of his/her own body. In cast disciplines like javelin throwing, the athlete must reach maximum performance with weight of the tool defined in advance. For instance, for a squat with jump performed by a discus thrower, the load of 30 % of maximal force was determined as optimum to reach maximal net power output. This phenomenon is used in training where it is possible to make load parameters individual and optimum to reach maximal net power output for a specific exercise (e.g. bench press).

Many motor skills contain the stretch shortening cycle (SSC). The principle of SSC is a combination of eccentric stretch and immediate concentric shortening of the muscle tendon complex during movement. With such a combination of movements, accumulated elastic energy during eccentric contraction is used. An example of this is landing after block in volleyball with subsequent move away from the net. At first, there is a stretch of the triceps surae and accumulation of elastic energy which is subsequently used while shortening during the first step away from the net. Motor skills which contain stretch shortenin cycle lead to improvements in mechanical efficiency of the movement, impulse of force and muscle power through elastic energy. Elastic energy applied during SSC positively affects muscle stiffness and neuromuscular activation. SSC is prevalent mainly in sports which include running, jumping, or other explosive changes in momentum or velocity.

Development of speed abilities is one of the most difficult tasks of training. It is because speed ability is to a great extent affected by innate dispositions (only about 20 % can be affected by training). Movement velocity is determined by mutual relationships of individual factors. Key innate factors affecting speed abilities are as follows:

  1. Qualities of the central nervous system, mainly the speed of stimulus transmission.
  2. The ability of the nervous system to quickly alternate stimulation and decrement during muscle innervation which directly affects the speed of contraction and relaxation of muscles.
  3. The ability of the central nervous system to react sensitively to only low level of stretch reflex which appears in the muscle spindle (muscle length sensor) and it evokes subsequent contraction during muscle stretch.
  4. The ability of intermuscular coordination between antagonist and agonist muscle groups.
  5. First, the amount of creatinphosphate (CP) and ATP for the start of motor activity and second, available amount of carbohydrates.
  6. Predominance of fast muscle fibers (muscle fibers of type II).

General parameters of load during speed development

  • Load intensity:maximal
  • Work interval:10 to 15s
  • Rest interval:2-5 min
  • Number of repetitions:10-15 repetitions
  • Way of rest:active

Load intensity:

Training performing speed is conditioned by maximum concentration on performed motor activity with maximum effort during the performance. If the motor activity is not performed with maximal intensity, there is no sense in carrying on with the training.

Work interval:

Work interval results first from the needs of specific sports performance and, second, it depends on selected development method.

Rest interval:

Sufficient rest interval during performing speed development is essential for:

  • Necessary resynthesis of energy resources (Table ).
  • Removing part of oxygen dept which appeared during preceeding anerobic activity.
  • Central nervous system recovery.

CP resynthesis depending on the duration of rest interval

Duration of rest interval (s)Repletion of CP (%)
<10 <50
30 50
60 75
90 88
120 94
>120 100

Number of repetitions:

The number of repetitions is determined by the moment of decrease in maximal intensity of the motor activity. If the trainees start to manifest signs of fatique, it is necessary to end speed training.

Way of rest:

During rest interval, it is recommended to employ additional movements of low intensity (walking, jog, trot, easy stretching etc.). An active way of rest keeps the activity of the central nervous system for further speed load.

The most favourable conditions for developing “pure” speed come at the age of 12-13 when the basis of neural manifestations, force mobility, lability and speed of neural processes is being created. Further improvement in speed occurs due to improved technique and strength abilities development.

Velocity of running

Bipedal running is a ballistic mode of locomotion with an alternating flight phase and single-leg support phase (by comparison, walking is nonbalistic without flight phase, and the stance alternates between double and single support phase). Sprinting is a series of running strides that repeatedly launch the athlete’s body as a projectile at maximal acceleration or velocity (or both), usually over brief distances and durations. Running speed is the interaction of stride frequency and stride length. Differences between novice and elite athlete:

  • Elite sprinters achieve greater stride length and are capable of increasing it up to 45 m from a static start, whereas novices achieve their maximum stride length at 25 m.
  • Elite sprinters achieve greater stride frequency (5 strides per second) and are capable of increasing it up to 25 m from a static start, whereas novices achieve their maximum stride frequency at 10 to 15 m.
  • Elite sprinters produce greater initial forces and velocities at the start and reach maximal velocities of up to 12 m/s after 5 to 6 seconds (45-55 m), whereas novices reach their top speed at 20 to 30 m.

Stride frequency also tends to vary among individuals and generally seems to be more trainable than stride length. As the athlete accelerates to his or her maximum stride rate, ground contact time decreases from 0.2 second during acceleration to 0.1 second at top speed.

The most basic aim of sprint training is to reach high stride frequency with optimum stride length in trajectory which can be desribed as explosive take-off with minumum vertical impulse.

Methods of developing speed and agility

The methods of developing speed can be divided into primary, secondary and tertiary. The methods must focus on key parameters which affect speed. Among the key parameters that influence speed, there are:

  • Force impulse
  • Net power output
  • Stretch shortening cycle (SCC)
  • Stride frequency
  • Stride length

Primary Methods

The primary method for developing speed is performing proper movement technique of a specific motor ability. The speed of performing an acquired skill increases depending on the quality of the skill. At the beginning of motor learning, the athlete should perform activities at submaximal speed to fix correct mechanism. As he or she gradually masters the skills, performence in the given task can come closer to or exceed full competition speed.

Secondary Methods

Secondary methods include sprint resistance and sprint assistance. The aim is to develop special skills in modified performance conditions.

Resistance method

This method includes gravity-resisted running (e.g., uphill or upstair sprinting) or other means of achieving an overload effect (e.g., harness, parachute, or weighted vest). The objective is to provide resistance without arresting the athlete’s movement mechanics, primarily as a means of improving explosive strength and stride length. In general, ≥10% changes in movement resistance have detrimental effects on technique.

Assistance method

Sprint assistance includes gravity-assisted running (e.g., downhill sprinting on a shallow 3-7°slope), high-speed towing (e.g., harness and stretch cord), or other means of achieving an overspeed effect. The objective is to provide assistance without significantly altering the athlete’s movement mechanics, primarily as a means of improving stride rate. Regardless of whether the athlete actually achieves overspeed or not, this method may also improve quality of effort during normal maximum-velocity sprinting by reducing the time and energy needed to accelerate. In general, apply assistance conservatively, exceeding maximum velocity by ≤10%.

Contrast method

It is based on the combination of resistance and assistance methods. Load under natural conditions is combined with load under difficult or on the other hand under easy conditions.

Tertiary Methods

Tertiary methods include flexibility, strength and speed-endurance training. Their aim is to develop general skills and abilities.

Flexibility

Flexibility represents an important condition for speed developing. Small joint scope and insufficient elasticity of skeletal muscles limits the athlete in maximum use of the overall capacity of the speed of a given movement. An example of this is insufficient stretching of the muscles of the back thigh the consequence of which will be limiting stride length while sprinting. An ability to fully stretch the leg before recovery stage is a predondition for reaching correct ready position on the groud and subsequently also landing. Inadequate flexibility may therefore result in incorrect foot posture, longer ground contact and bigger braking force while running..

Strength

Athletes must develop fast and reactive strength in order to maximise their speed and agility. This does not mean that they should only perform movements of low resistance and high speed during their training. The ability to reach high movement speed desires an ability to apply strength within the whole range of net muscle power output. Therefore, the program of strength traning must focuse on the whole strength-speed range .

Speed endurance

The issue of speed endurance can be viewed from two different perspectives. Speed endurance can be understood as an ability to maintain high movement speed for a time period exceeding 15 s, for example in running disciplines in athletics (200-meter and 400-meter running) when the athlete is trained for performance in a single run (qualifying, finals) which is followed by a sufficient rest period; or it is possible to be understood as an ability to repeatedly produce high movement speed with minimum rest intervals between individual repetitions. This model appears for example in ice hockey, florball etc., when the player must be able to repeatedly produce maximum performance during the whole course of the game. Load interval (time spent in the pitch) and rest interval (time spent on substitutes bench) then follow from practical requirements of the specific sport. An appropriate method to develop this tupe of endurance is represented by interval methods. An example of interval methods for developing speed endurance according to the creterion of load duration follows:

Speed endurance

Load interval:6-20s(20s-2mins)

Rest inteval:1:4(1:3)

Load intensity:maximal(maximal)

Way of rest:active(active)

The presented parameters are only of informative nature; in practice, it is necessary to watch for the moment of decreasing maximal intensity of performing the motor activity. As soon as there is a decrease in intensity, it is necessary to end this type of load. Duration of rest interval is also informative; it depends on immediate level of training. It is good to watch for the decrease in heart rate. The next load interval can start once the value has decreased to 120-130 b.p.m.

Developing Reaction Speed

In sports, reaction speed is manifested in different situations (e.g. the reaction of a sprinter to start-up shot, the reaction of a goalkeeper in football to direct free kick, the reaction of the coxwain to a sudden gust of wind in yachting etc.). The speed of reaction is determined by the time (latency period) which lasts from the stimulus to initiating a motor response by skeletal muscles. In sports, there are reactions to simple stimuli when the athlete knows the form of the stimulus exactly in advance (start-up shot at 100-meter run) and on the other hand, ther eis reaction to selective stimuli when the athlete expects one of possible forms of the stimulus (reaction to direct free kick in football, selecting the direction of movement of the central blocker in volleyball depending on the direction of the pass). A goalkeeper expects the ball to head for the goal but does not know to which part of the goal the ball is heading. Stimuli can be divided according to receptor involved into accoustic (start-up signal), visual (flight of a ball) and tactile (gust of wind through the sheets). Training reaction speed draws from simulating specific raction situations of a specific sports discipline. To train reaction speed, the athlete must be fully concentrated on the task being performed and he or she must not be tired.

Methods of developing reaction speed

Repetition method

The core of this method is repeated reactions to a given stimulus (e.g. reaction to start-up signal in swimming).

Sensoric method

The method broadens repetition method. The athlete attempts to subectively assess the duration of performing the reaction to a given stimulus.

Method of reaction to selective stimulus

A proper reaction to selective stimuli in sports games and resistance sports is often related to game experience and anticipation. An example of this is the reaction of the volleyball libero to the type of attack hit. Based on his or her experience, the player is able to anticipate the type and direction of intended attack following the clues provided by the movements of the opponent’s body. On the basis of his or her assumption, the player chooses the place of defense in field. A similar example can be found in resistance sports. A judo player attempts to anticipate the type and speed of the opponent’s entrance. The core of this method is to teach one’s trainees to gradually anticipate the opponent’s aim, thus gaining the most advantageous position for a reaction to difficult stimulus.

Basic Principles of Speed Development

  • The organism must not be tired.
  • The athlete must be in a good mood and must be self-motivated to train speed.
  • Speed training must be preceded by good stretching.
  • All exercises must be carried out with maximum intensity.
  • The technique of applied exercises must be perfectly mastered.
  • Speed exercises must be placed at the beginning of a training session.

 

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