A STUDY OF THE EFFECTS OF YOUTH COMPETITVE SPORTS ON

REPETITIVE MOTION INURIES DURING PUBERTY

by

Richard L. Brenkmann

A master’s project submitted in partial fulfillment of the requirements for the degree

of

Master of Education

in

Health, Physical Education, and Recreation

Approved:

Dr. John M. Kras, Chair Date

Dr. Richard Gordin, Member Date

Dr. Dennis Nelson, Member Date

Dr. Dennis Dolny, Department Head Date

UTAH STATE UNIVERSITY

Logan, Utah

2011

A STUDY OF THE EFFECTS OF YOUTH COMPETITVE SPORTS ON

REPETITIVE MOTION INURIES DURING PUBERTY

Problem Statement

When I was young, my friends and I played whatever sport was in season, except for the

summer when the sport relied on available shade. We never focused on any one particular sport

all the way through high school. Today’s youth are starting to focus on one sport at a much

earlier age in an attempt to elevate their abilities to a level of hopefully being able to become

professional athletes some day. Some kids are starting to specialize in competitive leagues as

early as eight years old, and really only playing that sport until they get out of high school. This

practice, I believe, is dangerous for the young person who does this. Many of these competitive

players end up with nagging injuries that plague them throughout their career.

Most of these injuries are from repetitive motions that put an unnatural strain on a

particular set of joints and muscles. These injuries are mere nuisances in the beginning, but

without proper rest and care the injuries will become chronic and more problematic as the child

gets older. These injuries are developing new names based on the sport such as soccer knee and

pitcher’s elbow. An individual who focuses on one sport also misses out on the skills that cross

over from one sport to the next, and can make a player an overall better player. By participating

in other sports, the joints and muscles will strengthen which could also prevent other injuries.

The literature suggests that youth who participate in only one sport, without decent rest, and

without experiencing “muscle confusion” (Bosgieter, 2010) can suffer overuse injuries that can

eventually develop into chronic injuries. The problem I will study is how prevalent are these

injuries in one sport participants between the ages of ten to 16 years old.

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Purpose and Objectives

The purpose of this paper is to show a correlation between the repetitive injuries and the

playing of only one sport during the developmental years through puberty. The objectives would

be to show to researchers and parents the need to participate in multiple activities to increase the

skills in the main sport. I would also hope to encourage parents and youth to consider playing

multiple sports because I do not know too many eight year olds who are already planning a career

in something specific. Burnout among these athletes is high because they have nothing else

going on but this one sport, and eventually they may grow to despise the sport. There are several

groups that have banded together to create “’the STOP Sports Injuries’ campaign to raise

awareness about this trend and help prevent athletic overuse and trauma injuries in children”

(Initiative to Stop, 2010). I would hope conscientious readers would realize that this is true and

encourage play for plays sake in their children.

Review of Literature

Competitive sports programs have been growing over the last several years with not only

local leagues, but regional and national leagues as well. There are competitive leagues in

basketball, baseball, soccer, hockey and rugby that have contests throughout the year. Most

competitive teams also play in tournaments on weekends all over the region in which they live, as

well as league games during the week. There are those who argue that the “all-embracing goal

for children's sport programs: helping young athletes emerge from the sport experience as

responsible, autonomous people” (Stiehl, 1990, p 207). “Coaches should include this goal in

their personal coaching philosophy and many have not done so” (Stiehl, 1990, p 207). This

responsibility should fall to “all adults, whether coaching or not, can help young athletes learn to

become responsible for themselves” (Stiehl, 1990, p 207). “Sports programs for young people

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have grown so rapidly that scholars and practitioners alike are hard pressed to keep up with new

knowledge” (Stiehl, 1990, p 205). It is not just the psychological toll, but also the physical toll

that youth face, especially in the repetitive actions that occur in competitive sports.

The adults who participate in competitive youth sports are the parents. The influence of

parents on the youth players is important in determining the efforts of the child, as well as the

level of soreness that the child will endure. “The degree of involvement a parent makes in their

child's sport makes a statement about the relative importance of this domain” (Barber, 1999). If a

child senses that playing and doing well is important to the parent, then the child “will adopt

values and beliefs similar to their parents” (Barber, 1999). Parents range in the level of

involvement from being over-involved to under-involved. Barber (1999) looked at the

relationship of parents to their children in youth sports, and found that youth participated for fun,

but initially for many it may have been encouragement from their parents to participate.

With the move to earlier specialization, it should be understood that “The American

Academy of Pediatrics (AAP) Committee on Sports Medicine and Fitness does not recommend

specialization before the age of 12 or 13 years” (Rosenbaum, p 255). The early start of sports

specialization can lead to injury due to micro-trauma to the growth plate. “Often, younger

athletes do not recognize overuse symptoms until they become debilitating” (Rosenbaum, p 256).

Rosenbaum also stated that “adolescents are not as coordinated or may not yet have adjusted to

physiological changes during an increased velocity of growth. This could result in altered

flexibility with inherent muscle imbalances, making them vulnerable to injury” (p 256). The

AAP recommends as an alternate to early sport specialization is sports diversification, which

would be considered as sampling (multiple sport experiences) from 6 to 12, and specialization

coming after in ages 13 to 15 (Rosenbaum, p 256).

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There have been a number of studies that have looked at various injuries in youth sports

and the causes behind them. Much of the literature focuses on the kinds of injuries associated

with contact or traumatic stress injury. The focus of my project is to look at repetitive use

injuries due to overuse and not enough rest between competitive activities. “Orthopedic surgeons

are also seeing a rise in the number of youth sports injuries in general, and in the number of

younger athletes who suffer overuse injuries” (Initiative to Stop, 2010). The literature that

focuses on the repetitive injuries seems to be mostly involving the sports of soccer and lower

extremity issues, and baseball pitchers with injuries involving the shoulder and elbow.

A New York Times Magazine article discusses the prevalence of elbow and shoulder

injuries in youth baseball. Berler (2009) did a study of the increasing number of youth players

who were having elbow and shoulder surgeries at much younger ages. “A 13 year old might

pitch Sunday for his travel team, Monday for his middle school team, and Wednesday for his

Babe Ruth team” (Berler, 2009). There are some players today who are “playing baseball nearly

year round, to the exclusion of all other sports” (Berler, 2009). “Parents failed to realize to

recognize that kids need 3 – 4 months of recovery time each year” (Berler, 2009).

Childress (2003) describes pitching as “one of the most dynamic motions in sport. This

is demonstrated when the average time from initial foot contact of the stride leg to ball release is

0.145 seconds” (p 1). Injuries to the elbow and shoulder are the normal injury site for youth

baseball players, with the most common being Little League Elbow. “The stress placed on the

elbow during pitching has been implicated as the cause of little league elbow” (Childress, 2003, p

2). Adolescent elbow injuries are repetitive injuries that are mostly skeletal in nature, and rarely

involve the muscle tendon that happens with adults. “When the elbow of an adolescent is

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subjected to repeated stress, the growth plates are more vulnerable to injury” (Childress 2003, p

3)

Other studies have shown that there is a deficiency in training and proper technique that

is the problem causing the shoulder and elbow pain. Aguinaldo, Butters and Chambers (2007)

looked at a concern described as “’throwing with too much arm,’ in which the energy from trunk

rotation is transferred to the upper arm too early and dissipated instead of being applied to the

hand and ball. (p 43) Aguinaldo, et al studied “the biomechanical patterns of trunk rotation and

shoulder joint torque during baseball pitching between professional, collegiate, high school, and

youth players.” (p 44) Although including some items from an older class, this information is

pertinent to this study because it helps to establish a background of the mechanics that make for

safer pitching. “The current study demonstrated that pitchers who rotated their torsos later in their

delivery exhibited less shoulder internal rotation torque (Aguinaldo, et al, 2007, p 48). Based on

their work, Aguinaldo, et al surmised “that the sequence of body segmental motion was

compromised when the trunk rotated too early, because part of the rotational energy was lost and

made up for by the upper extremity” (2007 p 48).

In a broader study of reported arm pain, Lyman, Fleisig, Waterbor, Funkhouser, Pulley,

Andrews, Osinski, and Rosman looked at 298 youth baseball pitchers over two seasons. The

study was designed “to evaluate the frequency of elbow and shoulder complaints in young

pitchers and to identify the associations between pitch types, pitch volume, and other risk factors

for these conditions.” (Lyman et al, 2001, p 1803) Each participant was contacted after a pitching

outing and asked a series of questions that would help the researchers “identify arm complaints.

Generalized estimating equations were used to assess associations between arm complaints and

independent variables. Results: The frequency of elbow pain was 26%; that of shoulder pain,

32% ” (Lyman, et al, 2001, 1803). Lyman, et al (2001) identified several risk factors that seemed

to be

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an underlying variable in both locations which included “playing baseball outside the league,

decreased self-satisfaction, arm fatigue during the game pitched, and throwing fewer than 300 or

more than 600 pitches during the season” (1803). It was also noticed that throwing more than 75

pitches in a game will also lead to shoulder or elbow pain. Lyman, et al (2011) concluded that

“arm complaints are common, with nearly half of the subjects reporting pain. The factors

associated with elbow and shoulder pain were different, suggesting differing etiologies.

Developmental factors may be important in both, to lower the risk of pain at both locations young

pitchers probably should not throw more than 75 pitches in a game” (1083).

In a different study by Fleisig, Weber, Hassell and Andrews (2009), they found that “the

risk of Adolescents who competitively pitch more than 85 pitches per game, more than 8 months

out of a year or with arm fatigue are several times more likely to require elbow surgery. Poor

pitching mechanics also appear to contribute to injury risk” (p254). Fleisig, et al. (2009) pointed

to “the number of pitches thrown has the strongest correlation to youth pitching injuries” (p 250).

Although Little League Baseball has created guidelines limiting pitch counts, “many independent

and travel teams have no rules restricting pitch counts, inning limits, or days of rest” (Fleisig, et

al. 2009, p 251). A player who may be a good pitcher could end up pitching 3 or 4 days a week,

throwing hundreds of pitches during that time. Major League baseball pitchers are monitored

constantly, and rarely throw more than 115 pitches in a week, and some coaches are asking youth

to throw more with less rest. Fleisig, et al. (2009) stated that: “Our impression is that in past

generations, most children engaged in a reasonable amount of sports participation; now, there are

many children who do not play enough sports, and a smaller ‘elite’ group of children who

participate too much in one particular sport” (p 252).

Ray (2010) took a more medical look at the injuries incurred by youth and found “that

taller and heavier children have an increased risk of injury to the elbow and shoulder than their

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counterparts of the same age. One possible explanation for this finding may include their higher

level of performance and subsequent overuse by coaches set on winning” (p 295). It seems that

many youth pitching injuries are blamed on the throwing of a curveball. Ray (2010) states

“shoulder internal rotation torque and proximal force as well as elbow varus torque and proximal

force were significantly less for the curveball than the fastball when comparing the biomechanics

of youth pitchers throwing the fastball, curveball, and change up. Although more research in this

important area is needed, this suggests that the curveball might not be more harmful to the youth

pitcher than the fastball” (p 295-296). More simply put, the torque from a properly thrown

curveball is less on the elbow and shoulder, and likely less harmful (although the emphasis

should be put on a properly thrown curveball) than a fastball or change-up.

Kocher, Waters, and Micheli (2000) also approached Little League Elbow from a more

mechanical standpoint, looking at the biomechanics of the injury. “Recognition of injury patterns

with early activity modification and the initiation of efficacious treatment can prevent

deformity/disability and return the youth athlete to sport” (Kocher, et al. 2000, p 118). Pitchers

suffer from “injury to the paediatric (sic) shoulder from throwing is a result of microtrauma (sic)

from repetitive motions of large rotational forces” (Kocher, et al. 2000, p 119).

Ogden and Warneke (2010) took a look at the correlation between college baseball

pitchers and youth competitive baseball pitchers as to whether these players had more need for

surgery later, and also had more pain from pitching. Select, or competitive, teams are starting

play earlier, as early as 7 or 8 years old, and these kids are encouraged to play year-round. As

stated earlier, it is recommended by researchers and doctors that players take up to 4 months off

of a particular sport in a year to rest and recover. Ogden and Warneke (2010) state “that the

youths who grow to be the best adult athletes are often those who engage in a variety of sports, or

multilateral development, in their earliest years. During those years children should be building

the basic skills of running, jumping, and throwing.” Although these select teams do seem to

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show a correlation to transitioning to the higher leagues, players were stricken with more stress

and burnout, and sometimes outright quit before reaching that level. Those who participated at

higher skill positions like pitcher and catcher also showed more signs of overuse injuries as they

progressed from level to level.

Studies have also looked at the incidence of injuries in youth soccer players. Just like the

use of the term Little League Elbow, soccer has its own malady of overuse called Soccer Knee.

This injury is characterized by the painful swelling of the patellar tendon, and is cause in large

part by the contraction of the quadriceps muscles to kick the ball and also to plant with the

opposite foot. This injury is less common in the recreational player who plays one game a week,

and practices once per week. Soccer Knee injuries are typically found in competitive soccer

players who will play and practice three or more times per week, and they often play 12 months

of the year. Another issue looked at by Viscovi and Van Heest (2009) was the number of ACL

injuries being suffered by female soccer players (p 394). The injuries in question are non contact

injuries that come from weak muscles that provide support to the knee joint. Viscovi and Van

Heest (2009) investigated the effectiveness of “the Prevent Injury Enhance Program” on

adolescent female soccer players (p 394). “Epidemiological studies with soccer players indicate

that the most common anatomical site for injury is the lower extremities. Of particular concern

for female soccer players is that following puberty they are three times more likely to suffer an

anterior cruciate ligament (ACL) injury compared with the male soccer players” (Viscovi and

Van Heest, 2009, p 394). Although this study was designed to look at injury prevention training,

it showed that part of this rash of ACL injuries could have as much to do with overuse. The

testing was conducted on four club soccer teams who were playing during a summer outdoor

season, with two teams running the training program and two who were doing an ordinary warm

up. At issue were the difference between warm up regimens and whether they decreased injury

or improved performance. There seemed to be no difference in the effects of the two warm-ups,

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and yet they were working with club athletes who played year round. The look at what was

happening in the injury situation could have been about rest time, time off, and healing of the

micro tears of the ligaments, tendons and muscles that occur when the adolescent soccer player

plays and practices 4 or more times per week. The study concluded “, these programs were

designed with an aim of reducing the risk of non-contact ACL injuries, not enhancing

performance. However, if we are to convince coaches to implement an injury prevention

program, then investigators and clinicians should continue to modify program variables and

develop regimens that have promise to deliver dual benefits – improved performance and reduced

injury risk” (Viscovi and Van Heest, 2009, p 401).

In a 10 year study of common injuries in elite youth French soccer players, Le Gall,

Carling, Reilly, Vandewalle, Church, and Rochcongar (2006) found that “players younger than

14 years incurred more injuries in training and sustained more growth-related overuse disorders.

Older players were more often injured during matches. Injury incidence and the frequency of

overuse disorders were highest early in the season” (p 928). The study seemed to suggest the

younger “players still lacked injury-avoidance skills or could have been undertaking too much

intensive training at this age” (Le Gall et al., 2006, p 934). Le Gall et al. (2006) further stated

that “injuries in less experienced, younger players may be owing to weaknesses in technical and

tactical ability as well as in muscle strength, endurance, and coordination” (p 934). “There was a

significantly greater amount of osteochondral disorders at the apophyseal or epiphyseal growth

areas of bones, which are linked to overuse, in U14 players, suggesting that this is a high-risk

group” (Le Gall et al., 2006, p 936).

Elias (2001) conducted a 10 year study that differed from Le Gall et al. by focusing his

study on injuries incurred during a major soccer tournament only. Elias chose the USA Cup

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Soccer Tournament held in Minnesota every July to study the injuries that were occurring during

the competition at all levels. This tournament lasts 6 days and has “over 800 teams from 23

countries participating in age groups under-12 to under-19. All games are played at the National

Sports Center/Blaine Soccer Complex, which has 55 fields on one site” (Elias, 2001, p 359). At

the end of the ten year study, Elias (2001) holds the notion that “although females are injured at a

rate slightly greater than males, there is a trend suggesting that the overall difference is becoming

less significant” (p 367). This was related to the aggressiveness of play between the sexes, as

well as the differences experienced in conditioning.

Gomez, Neufeld, and Cosby (1996) chose to determine whether middle school soccer

players could “assess the probability of success with which … players could correctly localize

lower leg pain to sites of common overuse injuries” (p 335). The goal is to develop an instrument

that will help youth understand and care for overuse injuries that can lead to significant injuries

later if not cared for early enough. “The majority of overuse injuries in young athletes occur in

the lower extremity. The common overuse injuries of the leg in youngsters include shin splints,

patellar tendonitis, plantar fasciitis, Osgood-Schlatter disease, and Sever disease” (Gomez, et al.,

1996, p 335). Gomez, et al. (1996) discovered that these nagging injuries were rarely significant

enough to warrant a trip to a doctor or trainer (p 338). “Since athletes with overuse injuries can

often ‘play through’ the pain, it may be more useful in evaluating the clinical significance of

these injuries to ask about the extent to which the pain compromised the athletes’ performance”

(Gomez et al. 1996, p 338).

With the recent emphasis being placed on head injuries, and the cumulative effects on the

brain of repeated minor concussions, a new field has grown out of competitive injuries involving

the heading of the ball. Contact among soccer players is generally not significant enough to

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warrant more than a look at contusions, but heading a soccer ball repeatedly can lead to minor

concussive events in the brain. Salinas, Webbe, and Devore (2009) looked at this phenomenon

and found that “the head injury rate accounts for 4.9–22% of soccer injuries in adolescents” (p

15). “The majority of soccer headings were direct rather than flicks. Almost half of our

participants reported headache and one-fourth reported dizziness after instances of heading the

ball” (Salinas, et al., 2009, p 15). “Children are even more likely to lack awareness of concussion

symptoms and so may not accurately report their symptoms. Without knowledge of such critical

information about their child’s symptoms, parents may not understand that these injuries require

medical attention” (Salinas, et al., 2009, p 16). Parents, coaches and players need to understand

both the symptoms and related problems that can come from repeated concussions. “In soccer

play, concussive head injuries are most likely to happen when two players make a mutual attempt

to head the ball. Heads banging together or elbows and fists striking a head are common. Less

common are injuries related to the ball striking the head” (Salinas, et al., 2009, p 17).

Discussion

As this information is looked at, I understand that repetitive injury is not limited to only

the competitive sports, but can occur in recreational sports as well. In a humorous article for

Sports Illustrated, Rick Reilly looks at what could be considered the absurd side of competitive

sports, but there still is the need to look at the potential for injury when a child who is still

growing plays one sport exclusively.

“But then my wife gets to talking to some other moms at Justin's slap shot workshop, and

they say we're crazy if we don't have a 'performance-enhancement specialist' for our kids.

So she signs them both up with one. Then she finds out most of these girls have

'recruiting consultants' who make highlight reels of kids and send them to college

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coaches. I'm like, 'She's 14!' And my wife is like, 'You're gonna tell our little girl no?'

Then we add a rating-service guy and a sports psychologist and a webmaster” (Reilly,

2006, p 76).

Competitive sports are leading to new needs in pediatric health as nagging injuries become more

serious in nature. “Because it's unrealistic to expect an enthusiastic young athlete or an

overzealous parent to recognize the severity of the issue and consequently know when to ease

back, it's up to recreation professionals and youth sports administrators to get the word out on

preventing overuse injuries” (Bach and Shilling, 2008, p 24). Bach and Shilling (2008) went on

to further state:

“Today's youth athletics are rife with single- sport specialization, heavy practice

schedules, and year-round training. The result is that a disturbing number of young

athletes have their seasons chopped short—and their long-term health jeopardized—by

overuse injuries.

As more and more youngsters are forced to visit doctors' offices for everything

from bone fractures and Little League elbow to shin splints and damaged knees, the

alarm is being sounded loud and clear by sports medicine professionals that too much of

the same activity can do more harm than good. Overuse injuries are sabotaging what

should be a fun and rewarding experience for millions of young athletes. These children,

who are breaking down due to the constant stress being placed on their young and

developing bodies, often face the unenviable prospect of long and sometimes painful

rehabilitations — and even surgery—to repair the damage” (p 24).

Conclusion

The youth are playing one sport exclusively more and more, and many are starting at a

much earlier age. The literature shows that, at least while growth is continuing to occur, there

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should be multiple sports tried by youth so that the muscles and bones can rest and recover.

Playing one sport year round never allows for the micro trauma to heal. I look at Washington

Nationals pitching phenom Stefan Strassbourg, and I see a young man who probably focused on

baseball at an early age. Granted, he signed a big money contract, but since being called up to the

majors at 19, he has spent more time recovering from elbow and shoulder pain than he has

playing. The micro trauma and lack of healing has caught up with him, and a bright future in

baseball is looking rather tenuous at this time.

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