Children, liki- adults, often need to do some exercises as part of their chiropractic treatment. But, how safe is exercise for children, especially exercise with resistance? How much weight is appropriate for a growing body? And which exercises are most effective? Because of these and similar questions, doctors of chiropractic may hesitate to recommend exercises for their younger patients. Let's see if we can arrive at a reasoned response, based on experience and useful consensus information. Passing Phases Prepubescence is the phase of childhood prior to the onset of secondary sex characteristics. Rapid, but variable growth occurs during this period, with open physes and changing muscle and ligament lengths. Adolescence begins with the onset of secondary sex characteristics and continues until physical and skeletal maturity. Selecting the best exercise approach for each child's situation is important, since needs may vary during growth.' However, all children should be encouraged to engage in frequent and regular fitness activities. Exercise Benefits The benefits of physical activity in youth include fitness, weight control, and the development of habits having the potential to span a lifetime. One study sys- tematically determined the amount of moderate-to-vigorous physical activity students obtain during elementary and middle-school physical education classes (time spent performing inod-eratc-to-vigorous physical activity compared to total class time). The researchers concluded that the amount of physical activity observed (elementary schools, 8.6%; middle schools, 16.1%) was significantly less than the estimated national average of 27%, and far below the national recommendation of a minimum of50%.2 A review of current youth fitness data indicates that children in the United States are fatter, slower, and weaker than children in other developed nations. Also, children in the United States appear to be developing a sedentary lifestyle at earlier ages. A low level of exercise is a contributing factor for childhood obesity and hypertension, and predisposes the individual to premature death from coronary heart disease.' Fortunately, through intervention in children and adolescents in the form of cduca- tion and motivation, exercise levels may be increased to the recommended minimum of thirty minutes on most days.4 Safety Issues High-intensity resistance training appears to be effective in increasing strength in preadolescents. Children make similar relative, but smaller, absolute strength gains when compared with adolescents and young adults. Resistance training appears to have little, if any, hypertrophic effect, but, rather, has been associated with increased levels of neuromuscular activation. Researchers have found that the risk of injury from prudently prescribed and closely supervised resistance training appears to be low during preadoles-cence.5 In 1993, Mazur, et a/., reviewed the types and causes of injuries to preadolescents and adolescents resulting from weight lifting/training. The researchers concluded that "prepubescent and older athletes who are well-trained and supervised appear to have low injury rates in strength training programs."6 A risk that must be considered in the immature skeleton is the susceptibility of the growth cartilage of the epiphyseal plates (physes). Weight training in a submaximal controlled, supervised situation is beneficial to bone deposition. Strength training can be a valuable and safe mode of exercise provided 1) instructors are properly educated; 2) participants are properly instructed; and 3) the absolute necessity of avoiding maximal lifts is reinforced.7 The most important factors in avoiding injury in children who are doing resistance exercises are proper performance of the exercise; avoiding overload by focusing on repetitions, not weight; enforcing rest periods during exercise; and resistance training only twice a week. Exercise tubing is an excellent tool for strength training of children, since the risks of injury are minimized, and a spotter or expensive equipment is not needed. Training Balance and Coordination For many children, it is more important to learn the fine neurological control necessary for accurate spinal and full body performance than to simply build strength. Better balance and coordination will often result in improved physical function, both in daily and in sports activities. This may entail performing exercises while standing on one leg, with the eyes closed, while standing on a mini-tramp, or using a rocker board. The advantage of these balance exercises is seen when children engage in sports activities and perform at advanced levels for their age group. All exercises are most effective when done in an upright, weight-bearing position, since the entire body is in a closed chain position during the training. The stabilizing muscles, the co-contractors, and the antagonist muscles all learn to coordinate with the major movers during movements that are performed during closed chain exercising. This makes these types of exercises very valuable in the long run, particularly for children who are interested in becoming competitive athletes. Corrective Postural Exercises Children's spinal problems are often associated with poor postural support. A spinal asymmetry, such as scoliosis and kyphosis, is invariably accompanied by neuromuscular imbalance. This may be compounded by poor postural habits and tendencies to "slump." One important factor in chiropractic treatment is the correction of any loss of the normal upright alignment of the pelvis and spine. In addition to general strengthening and coordination exercises, patients (including children) should be shown corrective exercises that are specific for the postural imbalances they have developed. For instance, when the pelvis is carried flexed forward, a patient of any age will need to retrain with resisted pelvic extension exercises. Likewise, when there is a forward head, posterior translation exercises for the cervical region are very important. Whenever a child shows evidence of abnormal gait or begins to develop lower extremity complaints, a careful evaluation for the need for shoe inserts is warranted. Custom-fitted orthotics can improve performance and spinal alignment by ensuring proper lower extremity alignment, and reduce overuse injuries by providing additional shock absorption. Conclusion A well-designed exercise program for children who need to strengthen, develop better coordination, and improve postural support will allow the doctor of chiropractic to provide cost-efficient pediatric spinal care. Exercises performed with the spine upright and functional can specifically train and condition all the involved structures to work together smoothly. In some children, orthotic support is necessary to help ensure correct alignment from the lower extremities. The end result is a more effective rehab component and young patients who will make a rapid response to their chiropractic care. With a few common sense precautions and careful supervision, children are capable of performing rehabilitative exercises very safely. QQ Kim D. Christensen. DC. CCS.P.. D.A.C.R.B.. founded the SportsMedicine & Rehab Clinics of Washington. He is a popular speaker, and participates as a team physician and consultant to high school and university athletic programs. He is currently a postgraduate faculty member of numerous chiropractic colleges and is the president of the American Chiropractic Association (ACA) Rehab Council. Dr. Christensen is the author of numerous publications and texts on musculoskeletal rehabilitation and nutrition. He can be reached at Chiropractic Rehabilitation Consulting. 18604 NW 64th Ave.. Ridgejield. IVA 98642 or by e-mail at kimdchristensen(a) hotmail.com See page 47 for References REHABILITATION-Pg 48 Children and Rehabilitation by Kim D. Christensen, D.C., CCS.P., D.A.C.R.B. American College of Sports Medicine. Guidelines for Exercise Testing and Prescription, 6th ed. Philadelphia: Lippincott Williams & Wilkins. 2000. Simons-Morton BG. Taylor WC. el al. Observed levels of elementary and middle school children's physical activity during physical education classes. Prevent Med 1994; 23:437-441. Cunnane SC. Childhood origins of lifestyle-related risk factors for coronary heart disease in adulthood. Xutr Health 1993: 9:107-115. US Dept. of Health and Human Services. Physical Activity ami Health: a Report of the Surgeon General. Atlanta: 1996. Blimke CJ. Resistance training during pre-adolescence: issues and controversies. Sports Med 1993: 15:389-407. Mazur LJ. Etman RJ. Risser WL. Weight-training injuries: common injuries and pre-ventative methods. Sports Med 1993: 16:57-63. Schafer J. Prcpubescent and adolescent weight training: is it safe? Is it beneficial? Natl Strength Conditioning Assoc J 1991: 13:39-45.?
