Update And Reflections On The Athletic Health Care System High School Injury Surveillance Study
By Stephen Rice, M.D., Ph.D., M.P.H.
Dr. Harmon Brown sent this one in, and at first I thought, "What is this about?" Then I read the first line. This article touches on additional aspects of coaching, such as men coaching women. It is of major importance and is reprinted with permission of the AMAA Quarterly, Spring 1997[11(2):5-9]. Stephen G. Rice, M.D., Ph.D., M.P.H., FAAP, FACSM, AMAA Contributing Editor, is Director, Primary Care Sports Medicine Fellowship, Director, Athletic Health Care System, and Co-Director, Jersey Shore Sports Medicine Clinic.
Imagine: girls' cross country running as the number one sport for injury among high school athletes. Impossible! Needless to say, these results of an ongoing injury study presented at the Fall 1993 annual meeting of the Greater New York Regional Chapter of the American College of Sports Medicine (and subsequently reported in the media that December) created quite a stir in the running community.
As the researcher of the Athletic Health Care System High School Injury Surveillance Study, I was a lightning rod for attention and criticism. Through this article, I would like to update readers on a new prospective epidemiological research study conducted this fall by a doctoral candidate, the data collected in the interim (1992-1995), and my reflections as to the possible reasons why girls experience so many injuries with running (and why the boys aren't too far behind).
Since the initial study used an injury surveillance design and not an epidemiological design, detailed data on each injured athlete was not available. Trends are clear, but reasons and causes are not elucidated. These must await the next series of studies: epidemiological and surveillance research to test given hypotheses.
Mitchell Rauh, P.T., a graduate student in epidemiology at the University of Washington in Seattle, undertook a study in the fall of 1996 to reconfirm the injury rates and to try to determine the cause(s) of injury among high school cross country runners in the Puget Sound area. Over 400 boy and girl athletes participated (essentially from the same schools that provided the data to this study). At the beginning of the fall cross country season, all athletes completed an extensive questionnaire of their past running and injury history, as well as their current (August) training regimen. In addition to keeping a running diary throughout the season, the athletes completed a post-season questionnaire. The research team obtained physical measurements of anatomic landmarks of the pelvis and lower extremity to identify anatomic variants and abnormalities which might predispose to injury. Finally, coaches submitted the daily team training log of their workout schedules and kept the same attendance/injury log (Daily Injury Report [DIR]) as they had since the inception of the study in 1979. Mr. Rauh hopes to complete his doctoral thesis paper by summer 1997.
MORE RECENT INJURY DATA (1992-1995)
In order to draw scientific conclusions from this massive bank of data (about 60,000 athletes in 18 sports participating for nearly 2.5 million days of activity through spring 1992), it was necessary to take the data and reenter all of it into a single integrated computer program. This painstaking process is now complete and analysis can now go for- ward systematically.
Further, entry of data from three additional school years (1992-93, 1993-94 and 1994-95) has also been accomplished. Over 6,500 athletes, who participated in over one quarter million days of activity, were added, contributing about 10% to 18% of the total athletic exposures in the data bank for each sport.
A preliminary evaluation of data from these recent three years on the first tier of "high injury rate" sports focuses on football, wrestling, gymnastics, boys' and girls cross country, and boys and girls soccer.
Football, girls' soccer and gymnastics showed dramatic declines in all injury rates (ranging from 12% to 39% in all injuries and from 14% to 57% in major [3-week] injuries). Boys' soccer was the lone sport among these seven to show an across the board increase in injury rates, with the greatest increases in one-week and three-week injuries.
Cross country runners had mixed but concerning experiences. The overall injury rate for girls was essentially unchanged (3% lower) while the overall injury rate for boys dropped 21 %. The rate for significant injuries (one-week) increased 30% in girls and 26% in boys. Since the girls' significant injury rate was already the highest among the 18 sports, a 30% increase is not encouraging. The injury rate for major injuries (three-week) increased in girls 11 % and increased 60% among the boys. The rate for major injuries among girls now places this result in a tie with wrestling for the highest major injury rate.
WHY DO RUNNERS EXPERIENCE INJURY SO FREQUENTLY?
What might be the etiologies which cause high injury rates among cross country runners? Four general categories require close inspection.
1. Running as an activity and sport
Cross country running is an aerobic endurance sport conducted in all types of weather on natural terrain and surroundings. Distance running is a contact sport, with the body contacting the ground 1,300 times per mile with each leg absorbing between three and six times the force of gravity on every step. This repetitive format, with its lack of variety, challenges the body to adjust to and adapt to these imposed demands of gravity. Running mile after mile eventually results in overload and microtrauma, to which the body responds either by acquiring new fitness or by falling into overuse injuries. Doing too much, too soon or too fast, failing to heed the wisdom of gradualness and moderation (the 10% increase per week guideline), has caused many athletes to succumb to overuse injuries rather than rise to new heights of conditioning and performance.
Runners would be wise to obtain and maintain some of their aerobic fitness through cross training, using swimming, bicycling, rowing or stair climbing to create variety in their training and avoid the "every step the same" dilemma of running. Following the theory of alternating hard and easy days, as well as taking one or two days a week off from running, would help preserve the legs from injury.
Runners must also become educated to the early signs of overuse injury so that problems can be detected immediately and time loss kept to a minimum. Athletes missing three or more weeks with severe shin splints or stress fractures represent a failure for all of us: runners, coaches, educators, athletic trainers and doctors.
The earliest sign of overuse (Stage l) entails pain following activity. The pain arises about two hours after a run, lasts an hour or two and goes away before bedtime and will not return until after tomorrow's run. This pattern will continue with the time of onset of pain getting closer to the end of the run each day.
Within a week or two, the runner enters Stage II, when this annoying but not debilitating pain comes on during the last quarter of the run and
continues daily for several hours. It subsides spontaneously, causing no pain while sleeping at night nor pain and stiffness in the morning, convincing the naive runner that it is not a significant problem (after all, "no pain, no gain!").
Running through this pain will result (in another week or two) in a Stage III overuse injury-pain coming on early in the run and clearly affecting performance. Not infrequently, this is the first time a coach notices a problem or the athlete admits that something is wrong. The runner may limp, be unable to complete the run because of the pain or may see either a plateauing in progress or an actual decline in performance.
Despite the disability and pain, many runners continue their efforts, advancing to the final stage of overuse, Stage IV. Here sharp pain will arise within a few steps of running or pain will be experienced simply doing the activities of daily living: going up and down stairs, carrying a backpack or book bag. Stage IV symptoms are equivalent to a stress fracture.
In Stage I, decreasing activity quantity and intensity about 10% will usually bring the athlete below the threshold of pain and thus continued running would remain acceptable. In Stage II, about a 25% to 35% decrease is required; in Stage III, about a 50% to 75% decrease is necessary and in Stage IV, all running must cease for several weeks in order to return to a pain-free state.
Ideally, each runner should have an individualized program designed to be commensurate with her ability to adapt to the challenge of exercise, factoring in her experience, ability, fitness, desire and anatomy.
One must be mindful of the mile- age run per day and per week; the pace (speed) of running; when and how speed work (such as interval training) is used; the amount, pace and striding when going up- and downhill, the schedule of hard and easy days and days off. Many runners will have no problems with mileage below 20 miles per week, but have sharply increased injury rates above that mileage. Some runners do well with short fast running but may have troubles with longer slow runs; yet others find the opposite to the be the case. There is no one correct way to train for everyone; trial and error plus individual coaching are critical. The basic rule of 10% per week increase in intensity (mileage and/or speed) may be practical for a recreational runner with lifelong fitness goals, but may be unrealistic for a competitive high school runner whose entire varsity season is about two months long.
Shoes and surfaces are important variables. Improper fit, inadequate impact-absorbing material, excessive stiffness of the midsole and! or insufficient support of the hind foot are common shoe-related causes of overuse injuries. It is essential that runners replace shoes when the mile- age run indicates that the shock absorbing capacity has been dissipated; after 400 to 600 miles, even shoes which appear to be in good condition will often fail to be adequate shock absorbers.
Running surfaces ideally should be level, soft and absorbent. Running on dirt or grass (free of ruts and roots) is superior to running on concrete or asphalt. Unyielding surfaces cannot share in dissipating the impact forces of landing, thus causing the legs of the runner to bear the full brunt of gravity.
Biomechanics and anatomical alignment provide the third and most challenging category of etiologies of overuse. The running form should be smooth and efficient, with fluid arm and leg movement accompanied by good posture. The support leg should land in such a manner as to absorb and dissipate the shock of landing, transferring from heel strike to midstance without excessive pronation and finally to propelling forward at toe off.
Common lower extremity problems which increase forces on the legs and decrease efficiency of running and shock dissipation include leg length differences, abnormal rotation at the hips (femoral anteversion), wide hips (pelvis), increased Q angle at the knee (>20°), bowleggedness, knock knees, excessive pronation, flat feet, high arched feet (cavus feet), tight plantar fascia and forefoot varus or valgus deformities.
Finally, muscle imbalances, lack of flexibility and lack of strength and endurance in the quadriceps and ham- strings, gastrocnemius and soleus, and anterior tibialis and posterior tibialis muscles can lead to overuse injuries.
Another factor which could play a role in the rate of injury of high school cross country competitors is the access to and availability of the sports medicine providers: are athletic trainers and team physicians routinely providing services to runners or are their efforts concentrated on the contact sports of football and girl's soccer?
2. Time of year: the fall season versus winter or spring.
Cross country is conducted nationally for high school athletes during the fall season, along with football, girls' soccer, volleyball and, in some areas, tennis and golf. In the Athletic Health Care System Injury Surveillance Study, fall sports had the highest rate of injury incidence while spring sports (track & field, boys' soccer, softball, baseball, some tennis and golf) had the lowest. Among all sports, girls' cross country clearly had the highest incidence of injuries, with boys' cross country in fifth place, behind football, wrestling and girls' soccer.
What factors should make fall sports the season of highest injury? By far the single most likely explanation is summer "idleness." Athletes who participate in sports or physical education during the school year from August through May may fall into a pattern of a lack of regular aerobic activity. Despite having a whole summer of unstructured "free time," many young people fail to maintain the discipline of staying in shape. Jobs, vacations, summer school and time spent with friends quickly fill up the hours of the day and evening. The deconditioning from not running results in loss of aerobic fitness and skeletal preparedness. Not having on-going contact with the coach often results in irregular, inconsistent and insufficient efforts at maintaining adequate levels of conditioning.
After a month or more of this deconditioning in June, athletes in many sports enroll in intense week-long summer camps, suddenly exposing their bodies to 8 to 12 hours of daily activity for five days. The combination of too little activity before camp coupled with too much activity during camp is a recipe for injury. Having paid several hundred dollars to attend the camp also tempts the sore athlete to ignore pain and keep on performing, to make sure he or she gets his or her money's worth from the opportunity. Failure to follow up with proper diagnosis, treatment and rehabilitation on signs of overuse injuries or mild to moderate traumatic injuries (strains and sprains) also can result in an athlete turning out in the fall in less than satisfactory condition. As soon as the rigor of training begins in earnest, these unrehabilitated injuries will commonly reappear.
For the highly competitive, experienced runner, however, the summer may provide the opposite of idleness: a lack of rest. Intense summer training and competitive programs send athletes and coaches all over the country and the world, displaying their talents and skills in some highly visible venues. I had one father call me saying his 10th grade daughter runs fall cross country, winter indoor track, spring outdoor track and summer competitive travel; she doesn't run only about 6 to 10 Sundays in an entire calendar year. "Is this reasonable?" he asked. Growing bodies need rest (but not too much).
In some parts of the country, including the Pacific Northwest, contact between athletes and coaches is carefully regulated in the three weeks prior to the first turnout to prevent a team from obtaining a competitive edge by practicing the skills of their sport. Conditioning per se, however, is permitted. For the football team, this could include strength training, distance running, sprints and agility drills, but nothing using footballs or drills which are similar to those run during the season. Try to imagine how a cross country coach can have contact with the team for the purpose of conditioning but not in any way involve running. The team could go on bicycle rides together, go hiking or take up rowing.
To me, these three weeks are very critical weeks. Since the time from the first turnout until the first competition is too short (10 to 14 days), it is essential that athletes attain a solid foundation of fitness prior to the first turnout.
It behooves all coaches, athletic trainers and team doctors to institute fitness screening for all athletes, ideally assessing the flexibility, strength, endurance and aerobic capacity early each June and again in mid-August to evaluate the readiness of each athlete. By having an individual prescription for each athlete in June, hopefully all athletes will be motivated not only to stay in shape but improve themselves over the summer so that they can beam with pride in their accomplishment when re-checked in August.
Given the choice between controlling unfair competition by unethical coaches (thereby creating the current proscription of contact between athlete and coach during the three weeks prior to the first turnout) or controlling the number and severity of injuries inflicted on unfit athletes every August and September, I strongly feel that August contact to get athletes ready for the first turnout should be encouraged and not banned. High school cross country has a very short season. Although teams may begin turning out around August 20, many delay the start until September 1. The first competition is in 10 to 14 days with the state championship held during the first week of November. In two months, boys and girls face more than half a dozen dual meets plus districts, regional and state meets. The college season, by contrast, begins in mid-August, has approximately the same number of dual meets and holds its national championship in the week prior to Thanksgiving in late November, generating a season which runs a full month longer.
Another factor of fall sports is the weather. Hot August weather can create problems associated with dehydration and heat illness while rainy and cold days in late October provide another set of hazards for runners dressed in short sleeve jerseys and shorts. Wet, slippery (and occasionally muddy) courses make running less than optimal.
3. The experience of the runners.
The third category is the experience of the runners. My intuition, informally confirmed with discussions among coaches and other sports medicine health care providers, is that athletes at the extremes of activity are getting hurt.
The novice athlete, who is not familiar with the specific skills and culture of a sport, often has done too little to prepare for the intensity of training. These individuals break down before ever getting their bodies built up.
The highly competitive athlete continues to push his or her body to its limits, often learning these limits only by experiencing injury. Despite having high levels of fitness, these individuals run until they break down. Too much mileage, too rapid a pace, improper interval training, over ambitious hill work and not enough rest all play roles in the injuries of the highly experienced runner. In addition, some of these athletes view ignoring the early signs of overuse as almost a ritual, denying the warning signs of pain to show their grit and character.
Among teams in the Athletic Health Care System Study small squad size (often less than 10 for girls) seemed to be a factor increasing the likelihood of injury. Young athletes are thrust into roles of competing in varsity meets when they would be better suited for a year on a "development squad." Veteran athletes with mild injuries who might benefit from rest and skipping a meet feel "obligated" to compete so the team can field a full squad.
To me, a warning sign for impending injury occurs with teams that have all athletes doing exactly the same training regimen without regard to ability, experience, technique or anatomy. One very successful method I learned from a local cross country coach is to pair athletes of like ability, with one running while the other rests. Very fit athletes thus run more and faster over a circuit, while slower, younger, less fit athletes cover the same ground (less often) at their own pace, placing none of the athletes at extra risk for injury.
Use of a fitness evaluation, biomechanical assessment, anatomy and alignment evaluation and a critique of the running form will provide a coach and sports medicine team with a plethora of information from which to create an individualized program or determine to which group the runner belongs.
4. Gender differences: girls compared to boys.
The fourth and final category is the gender issue. Why do girl cross country runners have more injuries than boys? Indeed in every sport where boys and girls do the same activity (running, soccer, basketball and track & field), girls have higher rates of injury whether looking at all injuries, those injuries lasting one to three weeks or those injuries lasting greater than three weeks. In this day and age, one must tread the waters of gender differences with great care, for no one wishes to be insensitive or offend females. With all such apologies, let me try to enumerate some key factors.
Do girls and boys have (or avail themselves of) equal opportunities to participate in physical activity and sports? Are boys and girls experiencing a different "culture" of sport in their youth?
High school coaches observe that there will never be a boy trying out for or making a team in a sport which he has never done before. Boys always bring experience to an inter-scholastic athletic activity, even if it's only informal sandlot or physical education experience. Boys with limited technique, mechanics and skills usually do not turn out for varsity teams.
Girls, on the other hand, may turn out for a volleyball or cross country team, never before having played that sport or ever being part of an organized team. These girls, then, are not used to "training" or "getting in shape." Further, some coaches feel that the motivation for participation among these girls is a social drive to belong to a team rather than an athletic drive to compete. Like any novice taking up a new activity, mistakes (injuries) will occur.
Further, girls who have not been regularly active in sports throughout childhood may have a less innate sense of the skills of physical education, such as in proprioception (body position sense) and body movement (kinesiology). These girls may be less able than boys to read the body's cues and clues: (1) When is enough activity enough (cues of fatigue)? (2) Where is my body in space and in relation to the ground? How do I stay in control? Among girl basketball athletes in high school and college, anterior cruciate ligament (ACL) injuries are becoming epidemic. One coach notes that female basketball players often lock their knees, something boys rarely do. Landing on a locked knee can force it into hyperextension, which is one of the key mechanisms for this devastating injury. (3) What are the early signs of overuse injuries? What does pain mean? Should I tell the coach or quietly suffer in pain? While some girls will report every ache and pain, many others keep silent too long, not realizing the significance and consequences of overuse injuries.
One potential issue is males coaching females. Are men sufficiently versed in the differences between boys and girls to make adjustments as indicated or will males typically push girls beyond their physical capacities? Will girl athletes be- have or respond differently to a male coach compared to a female coach? Would a girl be uncomfortable communicating with even a sensitive male coach, while she might feel more at ease sharing with a female coach? I have no opinion on this issue, but it should be explored in future studies. A major difference among males and females is known as the female triad, a combination of dietary and nutritional inadequacies, coupled with cessation of regular menstrual cycles and manifest with decreased calcium content in the bones. This unholy combination places all highly active women at markedly increased risk for injury with a special focus on girl runners.
An inadequate diet in calorie intake (< 2500 calories/day), calcium and iron can compromise the athletic performance of girls. Further, cross country running attracts girls with a tendency toward disordered eating (anorexia nervosa and bulimia). With a tendency toward leanness being an asset for runners, some girls will become anorexic as a result of running, while those already anorexic may be attracted to cross country as a seemingly legitimate way of further decreasing body fat to unhealthy levels.
Cessation of regular menstrual cycles (higher oligomenorrhea [an increased interval between periods] or amenorrhea [complete cessation of periods]) results from a lack of estrogen production. Theories abound as to why the reproductive endocrine system responds this way to heavy exercise, including decreasing body fat, increased stress, the shock of repetitive pounding with the ground from running and inadequate caloric intake. The consequence of decreased estrogen production and amenorrhea is the inability to retain ingested calcium in the bones.
The years between 15 and 35 are the only years a young woman can add calcium other bone mass. Failure to lay down calcium leads to thinner bones now and frank osteoporosis in one's senior years. Those runners with amenorrhea and decreased bone mass are at increased risk for stress fractures now; many by age 25 have bones similar in density to a 50 year old woman who never missed a menstrual cycle.
Excessive mileage often leads to amenorrhea. This coupled with an inadequate diet sets the triad in motion.
Males are less at risk because boys tend to eat sufficient calories and calcium, and the male hormone testosterone provides the foundation to maintain calcium in the bones.
Another unique phenomenon among girls compared to boys is that prepubertal or early pubertal girls can be competitive against peers and older girls. Gymnasts, ice skaters, swimmers, divers and tennis players, as well as cross country runners, between the ages of 10 and 15 have long histories of success against more mature older girls. This is not so with boys.
The example of Jennifer Capriati in tennis highlights the stress and emotional burnout that competitive child athletes experience. Many fail to perform well after age 18 and have an already long history of multiple injuries by the time they reach adulthood. It is no surprise to recognize that Andrea Jaeger and Tracy Austin and others made their contribution while in their teens and were pretty much out of tennis by the time they reached 20. Similarly, there are many stories of fabled young girl runners who burned out or had stress fracture after stress fracture by the time they reach college.
Although the issue of alignment, anatomy and biomechanics was mentioned previously, several points deserve additional emphasis. Women tend to have wider hips (in order to allow for bearing children within the pelvis) which leads to an increase in the quadriceps ("Q") angle. This phenomenon tends to cause the kneecap to track laterally instead of up and down. The sideways movement causes the underside of the patella to grind on the condyles of the femur (thigh bone). A major defense against lateral tracking is the strength of the vastus medialis obliquus (VMO) muscle of the quadriceps. Unfortunately, in girls this muscle tends to be underdeveloped and thus unable to adequately keep the kneecap within its normal tracking groove, leading to complaints of pain behind the kneecap (retropatellar pain).
This quick visit through the spectrum of possible causes of injuries to cross country runners should end with the notion that nearly all of these injuries are preventable. Unlike soccer, wrestling and football, where athlete-to-athlete body contact almost guarantees traumatic injuries, cross country running, with its abundance of overuse injuries compared to traumatic injuries, should be virtually injury-free if we could screen all athletes, ensure a proper summer fitness program, devise individual training programs, have cushioned and even running surfaces, have proper running shoes, recognize early any signs of overtraining or overuse and have ready access to high quality sports medicine care. It seems unacceptable that cross country running is keeping company with football, wrestling, gymnastics and soccer in the race for first place among high school sports injuries. This dialogue and opportunity to focus on reducing injuries is the most important by-product of this injury surveillance study. More research monies for further study of injuries in female athletes is indicated and appears to be on the horizon.
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4. Dougherty, K, Rice, S.G.: Cross Country: A High Risk Sport? Cross Country Journal. 1994;XI(6):1-8.
5. Rice, S.G.: Dr. Rice Reacts to His Injury Study. Cross Country Journal. 1994;XII(3):1-8.
6. Rice, S.G.: Sports Injuries Studied for 13 Years at 20 High Schools in Washington. National Federation News 1995;13(3):9-11.
7. Rice, S.G.: The High School Athlete: Setting up a High School Sports Medicine Program. In The Team Physician's Handbook, 2nd Edition. Mellion, M.B., Walsh, W.M., Shelton, G.L., eds. Phila- delphia, PA, Hanley & Belfus, 1997.
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