Children's Distance Running By Mark B. Levin, M.D. and Timothy J. Patrick-Miller, M.D. The Pediatric Group, P.A., Princeton

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Running has blossomed into a popular sport in this country. With our national concerns regarding cardiovascular fitness and weight control, this activity, requiring only appropriate shoes and a piece of ground, fits the bill for much of the population. For children, however, there are special considerations to heed.

Running is classified by the American Academy of Pediatrics as a strenuous, non-contact sport. Given the extra demands on the body, a diet adequate in protein and calcium (especially for female athletes) is mandatory. And, as in any other strenuous athletic endeavor, conditioning and stretching are paramount. Not realizing that they must condition and stretch as much as, if not more than, adults, many children experience preventable injuries. When children are participating in competitive running, they should stretch in the morning, in the evening, and before and after running events. Methods for stretching are best learned from a coach or fitness instructor. Be sure that all muscle groups- legs, hips, back and arms-- benefit from stretching.

Hydration is another critical consideration, especially in hot weather. Children often try to drink fluid after they run. But in this case, they are trying to recover from fluid losses sustained during the run and are, therefore, already in a deficit situation. They must not only re-hydrate, but they must also remember to pre-hydrate - drink fluids about 15-20 minutes before they run. In competitive distance races, the organizers often set up water tables along the route for in-transit hydration. Some runners carry a water bottle during their run for the same reason. In hot humid weather, a runner can lose a liter or more of water in an hour. Uncompensated fluid losses can lead to heat cramps, heat exhaustion or heat stroke. During muscular exercise, 75-80% of the energy metabolized goes into heat generation. Smaller runners have more body surface area compared to their body mass than larger people, which causes an increase in fluid loss per kilogram of body weight. Heavier people have less body surface area compared to their body mass, which causes them to dissipate heat less efficiently.

Heat induced muscle cramps are the first stage of heat induced disease. If they occur, the ailing person should seek a cool environment and drink fluids. Resting should continue until the symptoms subside.

Heat exhaustion is the next stage. It is defined by any of the following symptoms: fatigue, weakness, dizziness, light-headedness, nausea, vomiting, flushing, excessive perspiration, increased temperature, increased respiratory rate or decreased blood pressure. If this symptom complex occurs, the runner must seek a cool environment and drink 1-2 liters of fluid in 1-2 hours, even if thirst feels satisfied. Exercise should not be resumed the same day. Once the symptoms have resolved (they may last 2 or 3 days), careful exercise may be resumed.

Heat stroke is a serious final stage in heat induced disease. It is associated with altered mental state (loss of consciousness, psychosis or delerium), fever over 104oF or shock. A person suffering heat stroke must be transported to an emergency care facility at once. The risk for heat induced disease is greatest whenever the heat-humidity index climbs.

Many days during the last few harsh summers, the eastern United States has suffered through not just high heat-humidity index but high ozone levels and ultraviolet radiation exposure. Everyone, but especially those with a fair-complexion, should avoid being in the sun from 11 AM to 4 PM, and pre-apply sunscreen half an hour before running. During air quality alerts, all runners, but especially those with asthma, should avoid running between 10- 6 PM when vehicular-caused ozone is peaking.

Children susceptible to exercise-induced bronchospasm can experience wheezing while running, especially in cold weather. Some runners find relief by placing a loose scarf in front of the mouth so the inhaled air is warmer and more humid. Pre-hydration helps the cough that often follows running (prevailing theory holds that the cough is due to airway dehydration). Over time, even runners with reactive airway disease will develop exercise tolerance and endurance. If necessary, premedication to prevent wheezing may be warranted. Check with your child's physician regarding the advisability of this approach.

Running boasts one of the lowest frequencies of injury among sports participants. Although regular running induces a limited decrease in body mass, overall linear growth is unaffected in males or females (Eisenmann, 2002). Of course, anyone can twist an ankle by stepping in an unnoticed hole in the ground. It always pays to look where one is going! In adolescence, certain injuries are more common for certain body types. Runners with pronated feet (a condition where the foot rotates inward so that the person is standing more or less on the arch and the arch flattens to varying a degree) are at greater risk for medial tibial stress syndrome, commonly called "shin splints". This is six times more likely in female than in male high school athletes. (Bennett, 2001) The overall injury rate for high school runners is 1 ˝ to 8 times greater for females than males, especially in practices rather than in meets, and 75% of runners have to refrain from participation for up to 4 days in a season because of injury. (Raugh, 2000) Leg pains are more likely if running on a hard surface. The best surface is soft dirt, followed in order by a rubberized track, asphalt and cement. One study identified running for less than 8 ˝ years as a risk factor for shin splints. This study also showed an increase in spine and tibial stress fractures in female runners with very reduced lean body mass. Patello-femoral syndrome (knee pain due to friction between the knee cap and the thigh bone) was more common in males than females. (Taunton, 2002) For males, strength and flexibility increase by about 20% with each stage of puberty. In females, the major increase in strength and flexibility occurs just before mid puberty. (Pratt, 1989) In female runners, menstrual periods may be delayed or absent. Current thought holds that exercise-induced menstrual irregularities carry little medical risk.

Dr. Seymour Zimbler, Professor of Orthopedics at Tufts-New England Medical Center in Boston, comments that preadolescents should limit their distance running to 2 to 3 miles, 5 days per week, especially if they run on hard surfaces, if they have lax ligaments, or toeing in to avoid an overload syndrome. Swimming and biking are alternative activities for preadolescents who want more activity. He feels adolescents should limit their distances to three to five miles and should run on soft surfaces. (Pediatric Alert, 1987)

If a runner has any special medical problems, including but not limited to asthma, heart disease, diabetes or seizures, he or she should certainly consult with a physician prior to engaging in sports participation. Likewise, runners should be cognizant that specific geographic locations can have their own special risks. For example, runners in Lyme Disease endemic areas should consider wearing repellant and must check for ticks. With the appropriate precautions, runners can enjoy healthful outdoor exercise. See you on the countryside!

Dr. Mark B. Levin 

Dr. Levin has been a member of the staff at The Pediatric Group since 1977. Currently an attending Pediatrician at the Medical Center at Princeton, he has been Chairman, Department of Pediatrics, Medical Center at Princeton, 1984 to 1986, 1989 to 1992, and past President, Medical and Dental Staff, Medical Center at Princeton, 1987 to 1988. Dr. Levin has served on numerous Departmental and hospital committees. He has published original articles both while at Upstate Medical Center in Syracuse and at The Pediatric Group. He has a wife and three children. Dr. Levin enjoys alpine skiing, jogging, hiking and camping, travel, computers and racquetball.

Dr. Timothy Patrick-Miller Dr. Patrick-Miller has been a member of the staff at The Pediatric Group since 1985. Dr. Patrick-Miller has served on several Departmental and hospital committees. He has published original work while at The Pediatric Group. He and his wife enjoy travel. He also likes hiking, biking, gardening and reading.

ŠAll rights reserved, The Pediatric Group, P.A. 2002