Course:KIN366/ConceptLibrary/Throwing

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Movement Experiences for Young Children
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KIN 366
Section: 001
Instructor: Shannon Bredin
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Throwing is a complex ballistic and manipulative skill in which one or both arms thrust an object away from the body and into space (Gabbard, 2012). Ballistic skills are movements in which the person applies force to an object in order to project it. (Haywood, 2009) During early childhood especially, but even into adulthood, there is a large variety of throwing patterns. There is no definite order for the onset of variations; but they occur due to several factors: size of the object, size of the child, age, and previous experience (Gabbard, 2012). The three most common forms of throwing are overarm, sidearm, and underhand. However, overarm is used and studied most thoroughly (Gabbard, 2012). Various different methods and measurements are used to judge throwing abilities. These include: throwing for distance, throwing for accuracy, and measuring the initial velocity of the throw (Payne & Isaacs, 1995, p. 272; Wickstrom, 1983, p. 101). The most influential determinants for the development of a mature throwing pattern are early sport participation and sex. Meaning, the more sport exposure you obtain, the more likely you are to develop a mature throwing pattern; and boys achieve a mature pattern at a faster rate than girls (Butterfield & Loovis, 1993) Children are more likely to develop mature throwing patterns and improve performance with increasing workload and practice. (Marques, 2008) Game type and learning environment can also have a positive influence on the child’s motor development .

Early Experiences with Throwing

The first signs of overarm throwing appear around 6 months of age; this usually involves limited arm movement and is performed from a sitting position. If the child is exposed to proper practice, a mature throwing pattern can typically be developed by the age of 7. However there is a high incidence of individuals not reaching the mature stage (Gabbard, 2012).

Different Types of Throws Used in Common Games and Sports for Children

Throwing is used for a variety of purposes. Here are some games and sports featuring different types of throwing:

  • Hot Potato: underarm throw
  • Bowling: single arm underhand throw
  • Baseball: single arm overhand throw
  • Badminton: overhead clear
  • Soccer: two hand overhead throw
  • Ultimate: sidearm throw

Developmental Stages

In 1938, Wild identified 4 developmental stages of throwing through cinematographic analysis of the overhand throwing form of children aged 2-7. These are the stages and their characteristics.

(2-3 years)

-minimal trunk rotation.

-projection primarily through elbow extension.

-virtually all movement is in the anterior-posterior plane.

-feet remain stationary.

-body faces target.

(3.5-5 years)

-rotation of the pelvis and spine.

-allowing movement through the horizontal plane.

-feet generally stay stationary.

-greater force due to forward and downward follow through.

(5-6 years)

-step forward with delivery.

-during preparatory phase, weight is on back foot, and body rotated to throwing arm.

-arm is moved into a cocked position over the shoulder and set in a flexed position.

-weight is transferred onto the same foot as the throwing arm.

-incorrect step that needs to be fixed for a mature pattern.

-upon completion of the follow through, the body is rotated to the side that their body rotation took them.

(7 years: Mature Pattern)

-opposition by transferring weight to the foot opposite the throwing arm.

-facilitates greater trunk rotation and horizontal adduction of the arm during the forward swing. (Gabbard, 2012)

Developmental Characteristics

Immature stage

  • Ball held in palm of hand, fingers spread to release the ball
  • Action is caused by flexion and extension of elbow in anteroposterior plane
  • Elbow of throwing arm remains in front of the body: movement resembles a push
  • Trunk remains perpendicular to target, no rotation
  • Follow through is forward and downward, together with flexion of trunk
  • No weight transfer, feet remain stationary or purposeless shifting of feet

(Gallahue & Ozmun, 1998, p. 250; Williams, 1983, p. 234; Gallahue, 1989, p. 256)

Intermediate stage

  • Arms move backward and sideward behind head
  • Trunk and shoulders rotate towards throwing side in preparatory stage
  • Ball is held behind the head
  • Step forward with leg on same side as throwing arm
  • Arm is swung forward, high over shoulder
  • Follow through with trunk flexing forward with the forward motion of body and arm
  • Definite forward shift in body weight

(Gallahue & Ozmun, 1998, p. 250; Stewart, 1980b, p. 56; Gallahue, 1989, p. 256)

Mature stage

  • Arms swung backward and upward in preparation. Elbows fully extended to release ball
  • Opposite elbow is raised for balance as a preparatory action in throwing arm
  • Maximum trunk rotation
  • Step forward with the leg on opposite side of throwing arm
  • Follow through with hips, trunk, and arms
  • Shift weight to back foot in preparation

(Stewart, 1980b, p. 56; Williams, 1983, p. 234)

Wickstrom's 6 steps to a mature throwing pattern.

Preparatory Phase:

1. The body pivots to the right with the weight on the right foot; the throwing arm swings backward and upward.

Execution Phase:

2. The left foot strides forward in the intended direction of the throw.

3. The hips, followed by the spine and shoulders rotate counterclockwise as the throwing arm is retracted to the final point of its reversal.

4. The upper arm is rotated medially, and the forearm is extended with a whipping action.

5. The ball is released at a point just forward of the head with the arm extended at the elbow.

Follow-Through:

6. The movement is continued until the momentum generated in the throwing action is dissipated. (Gabbard, 2012)

It should be noted that the same individual will use different movement patterns for different task constraints in the same environment because every sport and game can require different variations of distance, accuracy and force to achieve the game objective. (Haywood, 2009)

How to Optimize Learning

Recommendations to Encourage Learning

  1. Begin by concentrating on throwing for distance, then progress to throwing for speed and eventually accuracy.
  2. Encourage speed of movement and hip rotation at an early stage
  3. Practice throwing with a variety of objects such as beanbags, rings, frisbees, balls etc.
  4. Have hoops or cones as cues to encourage stepping out on the opposite foot to throw
  5. Provide as many opportunities in different environments as possible to practice the movement.

(Dohorty, 2003, p. 78)

Common Mistakes to be Aware of in Early Learners

  1. Forward movement of foot on the same side as throwing arm
  2. Inhibited backswing
  3. Failure to rotate hips as throwing arm is brought forward
  4. Failure to step out with leg opposite the throwing arm
  5. Poor rhythmical coordination of arm movement with body movement
  6. Inability to release the ball at desired trajectory
  7. Loss of balance while throwing
  8. Upward rotation of arm (Gallahue, 1989, p. 253)

Influential Factors of Throwing Development

Age

There is a strong positive relationship between age and throwing development. As the child gets older they become more proficient in the preparatory movements necessary for throwing. (Haywood, 2009) They start to develop a circular arm action in which the arm moves down and back before cocking the elbow to get into throwing position. (Haywood, 2009) When the child progresses through the developmental stages of overarm throwing, velocity of throws will improve. (Marques, 2008) Therefore, it is important for parents and physical education leaders to be patient with a child’s throwing development because as they get older their performance will progress.

Sex

The constraints model provides the framework to categorize the factors influencing throwing development and performance during games into individual, task and environmental constraints. (Butterfield, 1993) These constraints can help account for the differences in throwing development between boys and girls of the same age. Individual constraints include factors such as body size, length of arm segments and neuromuscular coordination. (Butterfield, 1993) Boys tend to reach mature throwing patterns earlier than girls because of these constraints. Gender differences occur as early as 3 years old and are observed mostly in force of throwing. (Ehl, 2005) There are also large gender differences in product measures such as speed, distance and accuracy. (Butterfield, 1993) Therefore, a greater emphasis should be put on form when comparing throwing performance of boys and girls. (Lorson, 2008) Anthropometric measures such as joint diameters, shoulder-to-hip ratio and sum of skinfolds can account for the differences in throwing development in boys and girls. (Butterfield, 1993) Boys have a biomechanical advantage, which can lead to a strength advantage as well. Biological differences such as limb lengths and upper body mass can contribute to differences in throwing velocity. (Ehl, 2005) Weaker upper arm and shoulder girdle can lead to lower performance in force and distance of throws for girls. (Gallahue, 1989) Socioeconomic factors such as parental influence have an impact on the child’s sports participation. Boys were more likely than girls to be encouraged to participate in sports by their fathers. (Butterfield, 1993) Having a preference to participate in less physical and vigorous activities can affect the biomechanics and force of throwing, particularly for girls. (Ehl, 2005)

Learning Environment and Game Setting

Environmental factors can have a positive influence on developing fundamental motor skills. Key environmental factors such as the opportunity to participate in sports like baseball and softball are very beneficial to developing a mature throwing pattern. (Ehl, 2005) In a study involving American and German children’s throwing ability, American children performed much better because baseball and softball are more popular in the United States. In comparison, German children were more likely to play sports like soccer, which focuses on foot coordination. (Ehl, 2005) Environmental factors such as having opportunities to play with other children can account for differences seen in distance thrown. (Ehl, 2005) This is likely due to needing a partner to practice throwing and catching with.

The constraints of the game may affect the learning and development of the child’s throwing pattern. Controlled practice conditions involve the participant throwing at a desired target from a designated position to ensure stability of the testing environment. (Lorson, 2008) Usually the goal in a controlled practice is to throw at a specific target at a specific force and distance. (Lorson, 2008) Some games involving throwing require more accuracy, distance or force depending on the constraints of the game.

Game like environments include the task constraints of game rules and can encourage players to throw the ball more or less frequently, from different body positions and orientations, from different distances and aim at different targets. (Lorson, 2008) The goal in these types of games is to get the ball to a specific place within a specific time frame regardless of throwing form. The mechanics and components of the child’s throw will vary depending on whether form, accuracy, force or distance is the objective of the game. (Gallahue, 2008)

Type of Instruction

Immediate instruction is very beneficial to the development of correct throwing patterns. When a physical education professional gave instruction immediately after a practical throwing test, boys were more likely to use trunk rotation at the following retest. This trunk rotation is often the final step in developing a mature throwing pattern. (Lorson, 2008) After being given immediate feedback, girls improved their ability to step with their opposite foot and engage their trunk. (Lorson, 2008) Instruction was very beneficial for improving throwing performance in closed settings that later translated to improved performance in a game like setting. (Lorson, 2008) Physical education leaders should set up practice drills that resemble the task constraints of the game to encourage a more efficient skill transfer between practice and games. For example, if the final game requires fast and hard throws, children should practice lead up drills that improve their throwing velocity. (Lorson, 2008)

Physical educators often teach throwing with objects of different sizes and weights to cater to the developmental characteristics (physical, cognitive and social) of the individual. When learning to throw with different weighted balls, throwing velocity was improved. Practicing with an under-weighted ball always had a positive effect of increasing throwing velocity when they went back to using the regular ball of their sport. (Marques, 2013) Practicing with an overweight ball did not have as strong of a carryover effect as underweighted balls. (Marques, 2013) The total amount of workload is thought to be the main determining factor for increasing throwing velocity. (Marques, 2013) Throwing a number of variable distances improves accuracy of throwing compared to training to throw for a specific distance. Increasing workload and practice time has the greatest impact on improving throwing performance of children, including accuracy, velocity and distance. (Marques, 2013; Ehls, 2005)

Throwing Related Injuries in Children

Little League Elbow

Although there is an emphasis on increasing practice and workload to develop proper throwing mechanics to improve velocity, accuracy and distance of throws, it must be noted that there are concerns of overuse as well. There has been a rising incidence of youth athletes having arm injuries in sports such as baseball and softball. In recent studies, 20-40% of young baseball players have reported elbow pain. (Marsh, 2010) This injury is so prevalent in young athletes that it has been named Little League Elbow otherwise known as medial epicondylitis. (Marsh, 2010) It is due to excessive valgus stress put on the elbow during the cocking and acceleration phases of throwing. (Marsh, 2010) Since the young athletes are still developing they still have growth cartilage, which is less resistant to stress than adult articular cartilage. (Marsh, 2010) The most common factors related to Little League Elbow are improper pitching mechanics, high pitch counts, pitch type and poor physical conditioning. (Marsh, 2010)

Additional studies have shown that young baseball players between 9-12 years old that threw over 75 pitches a game or 600 pitches a year reported an increase in elbow pain. (Marsh, 2010) This is mainly due to muscular fatigue which is very specific to the individual but can be attributed to genetics, physical condition, rest duration between throwing, cumulative stress of the body throughout the course of the baseball season and total pitches thrown. (Marsh, 2010)

It is recommended that youth baseball players refrain from throwing curveballs and sliders. (These types of breaking pitches put extra force on the elbow because they require more forearm supination and wrist movement in comparison to the fastball, which can lead to elbow injury. (Marsh, 2010) As well youth athletes should refrain from participating in overhead sports for a minimum for 3 months each year to avoid throwing injuries. (Marsh, 2010)

Physical conditioning and warm up activities should be included in every young athletes program to prevent throwing related injuries. Warm up activities prepare the body for throwing by elevating core temperature, enhancing motor unit excitability, improve kinaesthetic awareness and maximize range of motion. (Marsh, 2010) Including a stretching and warm up component before any throwing is vital in prevention of elbow and throwing related injuries. The warm up should include jogging, dynamic stretches and basic fundamental movement skills. Resistance training can be beneficial for youth athletes if they are age appropriate. (Marsh, 2010) It is suggested that resistance training can start at 7 or 8 years old (Marsh, 2010) As well proper rest should be given to the athlete in between throwing sessions.

Prevention

If Little League Elbow does occur, the treatment suggested is resting for 6 weeks to 6 months or till pain resides, depending on the severity of the injury. But taking precautions such as teaching proper throwing mechanics and limiting the number of pitches are the best actions to preventing the injury. (Levy, 1993)

Keys for Learning

  • Adequate opportunity for practice before the age of 7. This is especially critical for girls development. (Gabbard, 2012).
  • Exposure and experience will progress the child to a mature throwing pattern better than any specific toy or apparatus. Practice and repetition is necessary for development and improving different aspects of throwing performance.
  • A structured guided practice schedule doesn't facilitate throwing velocity improvements. Instead throwing should be practiced on a variable schedule with a mix of structured sport, physical education class and free play (Halverson, Roberton, Safrit, & Roberts, 1977)(Vera & Montilla, 2003).
  • Since the overarm throw is a fundamental movement skill, if the child has difficulty throwing they may be unable to transfer the skill into a more complex sport specific skill such as pitching in baseball or spiking in volleyball. (Marsh, 2010)

Take Home Message From the Above Research

Every child will develop at a different rate and show different developmental patterns. Children may not always follow the proper biomechanics of throwing but they can still develop an effective pattern depending on their physical development, proportions and game constraints. Ensure that between the ages of 2-7, the child obtains plenty of throwing experience within a variety of different practice and game environments. Increasing the amount of workload and repetitions of throwing seems to have the greatest effect on throwing development. More attention should be focused on how the child is performing the skill (form) rather than how successful they are at using the skill (performance). (Virgilio, 2006) If the child develops a mature throwing pattern at an early age they will continue to use and practice that motor pattern which will transfer to learning additional sport specific skills later in life. Without this initial fundamental motor movement, the child’s ability to learn and play sports with any overhand throwing movement will be hindered. If there is a deficit in fundamental movement skills, the child’s physical, social and cognitive development will be limited because because this delay in development will limit their opportunity for new experiences. (Doherty, 2003) During throwing development in youth sports volume, distance and types of throws must be monitored in order to prevent elbow, shoulder and throwing injuries caused by overuse.


References:

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