FITNESS 101
Click on the articles below for fitness tips.
• Exercise Science: Aerobics for Maximum Fat Burning
• Two Trains of Thought about Training
• Muscles are recommended...
• Strength Training for Children
• Training Techniques
• Destroy Fat Cells
• 7 Weight Loss Winners
Click on the articles below for fitness tips.
• Exercise Science: Aerobics for Maximum Fat Burning
• Two Trains of Thought about Training
• Muscles are recommended...
• Strength Training for Children
• Training Techniques
• Destroy Fat Cells
• 7 Weight Loss Winners
Strength Training for Children
A true perspective on the facts and fallacies of children's strength training removes a programming barrier to preadolescent activity.
By Rachael E. Picone
June 1999
Despite increasing acceptance of strength training for preadolescents, some parents, coaches and instructors, concerned with children's physiological and psychological well-being, are skeptical that strength training offers benefits without causing harm. Myths and misinformation have helped persuade many to disapprove of preadolescent strength training. This is changing, however, as new knowledge replaces old misconceptions.
Facts about strength training
Preadolescent boys and girls can see meaningful gains in strength with proper training. Although it has been documented that adults and adolescents can achieve significant improvements with strength training, training gains for children have been questioned. The argument that led to the false belief that children couldn't benefit from training was based on two presumptions. First, it was considered unlikely that notable changes in muscular strength and endurance could occur prior to puberty, due to lower levels of circulating androgens (e.g., testosterone). The underlying assumption was that higher levels of androgens were necessary for improvements in muscle size and strength to occur. Second, children naturally become stronger as they grow, and strength gains beyond that were thought improbable. Previous studies, which seemed to support this, were often limited in study design and research methodology (such as low intensity, low volume or short duration training protocols). Nevertheless, these data seemed to suggest that resistance training was ineffective in the very young population.
A growing body of scientific evidence in support of children's strength training has arisen within the past 15 years. The literature provides strong documentation that both male and female preadolescents can improve strength significantly with well-designed resistance-training programs. Recent reviews analyze the available research by comparison. Although a relatively small number of studies were included, one review revealed that a majority of studies demonstrated strength gains between 13 and 30 percent as a result of training.9 Another reported similar results for children and youth, and each of the studies included in this review indicated that resistance training was generally effective, regardless of participants or study characteristics.12
Gains from strength training for preadolescents are generally attributed to neural adaptations and motor learning, rather than circulating androgens. Muscle hypertrophy, or an increase in the cross-sectional area of a muscle, is not usually detected in children as a result of training. Since muscle size has been correlated with strength, studies indicating no increase in muscle hypertrophy implied that strength training was ineffective in younger participants.
Strength-training studies performed on adult subjects augment understanding of children, and have demonstrated that neural adaptations occur with training. Neural adaptations in preadolescents are cited as being similar to those in adults and include an increased frequency of motor-unit firing, improvements to motor-unit activation and synchronization, and the reduction of inhibitory signals on motor units from central nervous system pathways. Although muscle hypertrophy from training in children still remains a possibility, the majority of recent findings suggest that improvements in strength are independent of changes in muscle size.
The benefits of strength training in preadolescents deserve more attention and application. The preadolescent population can derive numerous benefits from strength training, which can outweigh any possible risks. These include, but are not limited to, improved muscular strength, endurance and flexibility; prevention of bone loss and osteoporosis; improved self-image, confidence and well-being; improved motor coordination and sports performance; decreased risk of injury; lowered blood pressure and cholesterol levels; weight maintenance; neuromuscular therapy and physical rehabilitation; promotion of lifetime physical activity; and improved aerobic capacity.
One of the most promising benefits of strength training may be increased bone mass. Bone mass, or bone density, continues to increase throughout growth and development, but a peak in bone mass, called the peak bone mineral density (PBMD), is reached at a young adult age. Attaining a higher peak bone mass as a young adult may delay the age at which a loss of bone from aging occurs. A loss of bone later in life, especially among menopausal women, can lead to osteoporosis, causing bones to become increasingly porous, brittle and fragile.
So, is it possible to influence bone mass during the first two decades of life to achieve a higher PBMD? Weight-bearing physical activity such as walking, jogging and strength training has been shown to have a positive effect on bone density by mechanically loading the skeleton. Though the precise amount and intensity of activity necessary to improve PBMD is uncertain, the importance of promoting load-bearing physical activities such as strength training for growing children is evident.
Although enhanced sports performance is another benefit of strength training, it has not been thoroughly studied, and it is questionable whether a young child should lift weights solely for the purpose of improving performance. The average young athlete is not competing at a high level, but rather developing basic skills necessary for future sports participation and success. Coaches must carefully weigh the level of competition, emotional maturity of the child and the possible benefit of decreased injury before recommending a strength-training program.
Children who strength train should follow a structured program that is taught and supervised by qualified instructors. Children are affected by interacting components such as musculoskeletal growth and sexual maturation. Therefore, borrowing exercise prescriptions from adult strength-training programs is inappropriate. For example, pushing to failure and performing forced repetitions or exaggerated eccentric contractions may be dangerous. Prepubescent children should not be expected to respond -- either physically or psychologically -- as adults do. Exercise prescriptions must be tailored to their individual needs, and program supervision must be exceptional.
Optimal prescription parameters, such as the number of sets and repetitions, have yet to be defined for the preadolescent population. It is recommended that children use the minimum dosage of training that produces beneficial improvements in strength and health without undue risk. Of all of the strength-training parameters, exercise intensity seems to be the key determinant of an effective program. Present guidelines suggest that intensity be moderate (approximately 10 to 15 repetitions) and that preadolescents avoid maximal lifts. A child should begin a program with one set of little or no weight and concentrate on learning proper form. Once proper technique is demonstrated, a resistance can be selected that allows approximately 10 repetitions to be performed. The number of repetitions is slowly increased until the maximal number (15) can be completed. Resistance is then advanced in small increments of one to three pounds. As the child advances, one to three sets can be performed as tolerated.
To achieve balance between agonist and antagonist muscle groups, eight to 10 exercises should be performed, with at least one for each major muscle group. The sequence of exercises should progress from larger muscle groups to smaller ones, and the frequency of training can start at two days per week and advance to three, as long as at least one day of rest is permitted between each training session. Workouts of approximately 30 minutes should be preceded by an appropriate warm-up and finished with a cool-down. Proper training techniques, such as lifting in a controlled manner, must be demonstrated and consistently emphasized throughout the program.
Safety considerations in any preadolescent physical activity program include proper instruction and close adult supervision. Improper instruction can lead to poor technique, which can cause acute and chronic injury. Weight-training literature points out that many injuries are the result of accidents (often from using excessive weight in power lifting) and unsupervised training.
To minimize the risk and maximize the benefits of strength training, health/fitness professionals and coaches must act responsibly by taking precautions before, during and after exercise sessions. It is imperative that they possess the background knowledge and experience to handle the preadolescent population. Instructors working with children should hold a degree in a health-related field such as exercise science or athletic training, as well as have current CPR and first aid certifications. There should be a small staff-to-participant ratio that is dependent on the number and ages of participants. For example, a class of more than 10 older children should have at least two instructors, with more staff added for larger groups.
Fallacies about strength training
Children should not lift weights before the age of 12. Twelve years of age is often used as a chronological marker for puberty since it is generally reached by age 12 for girls and age 14 for boys. Because of their immature skeletons, weight training was believed to place preadolescents at high risk for injury, and even possibly to interfere with normal growth. Therefore, many people recommended that children wait until puberty before participating in a strength-training program.
Chronological age, however, does not take into account the wide variation in the onset, progress and completion of biological growth and maturation. As a child enters the adolescent period, obvious changes in height, weight and sexual maturation occur. Skeletal maturation, though difficult to observe, is also occurring. All children proceed through growth and maturation in the same sequence, but a key difference is the rate of this process. There is such variation in the rate of physiological change that it becomes nearly impossible to compare preadolescents of similar chronological age without assessing their stage of maturation. Two 11-year-olds in the same activity class, for example, may be at very different degrees of growth and development. Although various methods of assessing maturity do exist, they are impractical for the fitness instructor or coach, and no single test gives a complete picture of individual growth and maturation.
Strength training will stunt growth in children and delay the age of menarche in girls. Recent studies indicate that growth and development is not affected -- either positively or negatively -- by a wide range of sports and training. A longitudinal British study called The Training of Young Athletes (TOYA) Study investigated the relationship between sports participation, growth and sexual maturation. Gymnasts, swimmers, and soccer and tennis players ages eight to 17 were followed over a three-year period. Results suggested that regular training does not adversely affect growth or sexual maturation, but rather that sport-specific selection occurs.
This acknowledged "pre-selection" for specific sports reflects a probable biologic and social selection among young athletes. For example, a basketball or volleyball coach may approach taller individuals to inquire about their interest in participation. Pre-selection for athletic success may favor either a late- or early-maturing child, depending on the specific size demands of a sport. Boys tend to compete in activities that require strength and power; therefore, early maturers who are taller and stronger may be at a performance advantage and are often more likely to participate.
Although the onset of menstruation is related to factors such as genetics and environment, the hypothesis that intensive training at a young age causes changes in biologic maturation has persisted. Based on this theory, many have suggested that young girls should not participate in sports. But sport-specific selection is also cited as a reason that young girls appear to be delayed in menarche. Activities that girls may be inclined to participate in, such as dance and gymnastics, may favor a late-maturing girl. Those who experience earlier changes in body composition and stature may be socialized away from sports that are biased toward a pre-menarcheal body type. There is currently no concrete data to implicate physical activity as a cause of delayed sexual maturity in girls.
Lifting weights will cause harm and injury to a child's bones, muscles and joints. In 1990, the American Academy of Pediatrics recommended that children and adolescents avoid weightlifting, powerlifting, bodybuilding, and lifting maximal amounts of weight until reaching Tanner Stage 5 of biological maturation. (Sexual or biological maturation can be assessed by a 5-point scale referred to as Tanner Staging, usually determined by a physician or nurse.) Styles of Olympic and powerlifting call for single-repetition maximum lifts, while bodybuilding is associated with high volumes of training to increase mass. These activities are competitive sports and should be highly discouraged in the growing child and adolescent. However, appropriate, safe and well-supervised strength-training programs in a school or health club that are intended to improve muscular strength and endurance can be an appropriate part of an overall physical activity program.
The concern about musculoskeletal injury and epiphyseal fracture may seem reasonable; a child's skeleton is maturing and damage to the bones and epiphyses, or growth plates, is potentially serious. Although the understanding of injury is somewhat limited by a lack of risk-factor studies, skeletal immaturity may be only one small component of weight-training injuries in children. Additional contributing factors to both acute and chronic injury include improper training techniques, lack of supervision, excessive loading, unsafe ballistic movements (e.g., clean and jerk), steroid abuse and repetitive abuse (overuse syndrome). Epiphyseal fractures have been reported in children and adolescents as a result of weight training, but are most often attributed to one or more of the preceding factors. It has been stated that growth plates are actually stronger in childhood than in adolescence, and that the concern over epiphyseal fracture may be overstated. More research is needed to determine the risk of injury from weight training, but current data suggest that the risk is no higher than that of participating in other sports. The risk of injury can be minimized with a properly designed training program and close adult supervision.
Conclusion
As the benefits of strength training become increasingly clear, it will undoubtedly become more popular among preadolescents. In 1996, the Centers for Disease Control reported that nearly half of young people ages 12 to 21 are not vigorously active, and that physical activity declines during the adolescent period. Perhaps the most valuable lesson to teach the youngest generation is how to develop a lifelong habit of physical activity. Promoting a healthy lifestyle, maintaining the habit of activity throughout the school years and preventing sedentary behaviors in adulthood will benefit not only today's children, but also future generations to come. FM
REFERENCES
1. American Academy of Pediatrics. Strength training, weight and power lifting, and bodybuilding by children and adolescents. Pediatrics 86(5): 801-803, 1990.
2. Armstrong, N., & J. Welsman. Young People and Physical Activity. Oxford University Press: N.Y., 1997.
3. Baxter-Jones, A.D.G., & P. Helms. Effects of training at a young age: A review of the Training of Young Athletes (TOYA) Study. Pediatric Exercise Science 8: 310-327, 1996.
4. Blimkie, C.J.R., & O. Bar-Or (eds.). New Horizons In Pediatric Exercise Science. Human Kinetics: Champaign, Ill., 1995.
5. Blimkie, C.J.R., & O. Bar-Or (eds.). Resistance training during preadolescence: Issues and controversies. Sports Medicine 15(6): 389-407, 1993.
6. Bryant, C., & J. Peterson. Not for adults only. Fitness Management 34-36, June 1996.
7. Brzycki, M. Youth Strength and Conditioning. Masters Press: Indianapolis, Ind., 1995.
8. Cahill, B. (ed.). Proceedings of the Conference on Strength Training and the Prepubescent. American Orthopaedic Society For Sports Medicine: Chicago, Ill., 1988.
9. Falk, B., & G. Tenenbaum. The effectiveness of resistance training in children: A meta-analysis. Sports Medicine 22(3): 176-186, 1996.
10. National Strength and Conditioning Association. Youth resistance training: Position statement paper and literature review. Strength and Conditioning 18(6): 62-75, 1996.
11. Ozmun, J., A. Mikesky & P. Surburg. Neuromuscular adaptations following prepubescent strength training. Medicine and Science in Sports and Exercise 26(4): 510-514, 1994.
12. Payne, V.G., J.R. Morrow, L. Johnson & S.N. Dalton. Resistance training in children and youth: A meta-analysis. Research Quarterly of Exercise and Sport 68(1): 80-88, 1997.
13. Reeves, R., E. Laskowski & J. Smith. Weight training injuries: Part 1: Diagnosing and managing acute conditions. The Physician and Sportsmedicine 26(2), 1998.
14. Reeves, R., E. Laskowski & J. Smith. Weight training injuries: Part 2: Diagnosing and managing chronic conditions. The Physician and Sportsmedicine 26(3), 1998.
15. Rowland, T. Exercise and Children's Health. Human Kinetics: Champaign, Ill., 1990.
16. U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Physical Activity and Health: A Report of The Surgeon General, 1996. Teaching Children Strength Training
* Request a complete physical exam and clearance form from all participants. Screen for any special health conditions and possible contraindications, such as chronic cardiovascular problems.
* Welcome only those participants who are emotionally mature enough to accept instruction and adhere to all policies and procedures. Have a definite course of action for disciplinary procedures and dismissal.
* Endorse strength training as one part of a total health and fitness program. Promote all components of a healthy lifestyle, including aerobic fitness, flexibility, proper nutrition, wellness and playtime.
* Evaluate equipment suitability for the age, size and maturity of the child using it. Inspect all equipment for safety prior to use. Make the most of available options, including dumbbells, resistance tubing, bands and body weight.
* Emphasize and enforce safety at all times. Never turn your back to participants. Be cognizant and pay close attention to each participant.
* Provide a thorough warm-up and cool-down for each exercise session.
* Allow adequate water breaks and suggest that children bring water bottles.
* Always accentuate proper technique such as a full range of motion, slow repetition speeds, proper body alignment and proper breathing.
* Clearly discourage competition. Remember that each child will progress at his or her own pace and that biological age is not an accurate predictor of readiness or performance.
* Incorporate weekly educational lessons about health, fitness and nutrition. Recommend quality resources including magazines, books and Websites to both parents and children.
* Encourage children to play an active role in their program. Use workout cards to monitor progress and solicit questions.
* Use a creative approach to design a variety of enjoyable workout programs and incentives (circuit training, small prizes and certificates for participation).
* Be a positive role model by encouraging and motivating children to strive for their personal best.
A true perspective on the facts and fallacies of children's strength training removes a programming barrier to preadolescent activity.
By Rachael E. Picone
June 1999
Despite increasing acceptance of strength training for preadolescents, some parents, coaches and instructors, concerned with children's physiological and psychological well-being, are skeptical that strength training offers benefits without causing harm. Myths and misinformation have helped persuade many to disapprove of preadolescent strength training. This is changing, however, as new knowledge replaces old misconceptions.
Facts about strength training
Preadolescent boys and girls can see meaningful gains in strength with proper training. Although it has been documented that adults and adolescents can achieve significant improvements with strength training, training gains for children have been questioned. The argument that led to the false belief that children couldn't benefit from training was based on two presumptions. First, it was considered unlikely that notable changes in muscular strength and endurance could occur prior to puberty, due to lower levels of circulating androgens (e.g., testosterone). The underlying assumption was that higher levels of androgens were necessary for improvements in muscle size and strength to occur. Second, children naturally become stronger as they grow, and strength gains beyond that were thought improbable. Previous studies, which seemed to support this, were often limited in study design and research methodology (such as low intensity, low volume or short duration training protocols). Nevertheless, these data seemed to suggest that resistance training was ineffective in the very young population.
A growing body of scientific evidence in support of children's strength training has arisen within the past 15 years. The literature provides strong documentation that both male and female preadolescents can improve strength significantly with well-designed resistance-training programs. Recent reviews analyze the available research by comparison. Although a relatively small number of studies were included, one review revealed that a majority of studies demonstrated strength gains between 13 and 30 percent as a result of training.9 Another reported similar results for children and youth, and each of the studies included in this review indicated that resistance training was generally effective, regardless of participants or study characteristics.12
Gains from strength training for preadolescents are generally attributed to neural adaptations and motor learning, rather than circulating androgens. Muscle hypertrophy, or an increase in the cross-sectional area of a muscle, is not usually detected in children as a result of training. Since muscle size has been correlated with strength, studies indicating no increase in muscle hypertrophy implied that strength training was ineffective in younger participants.
Strength-training studies performed on adult subjects augment understanding of children, and have demonstrated that neural adaptations occur with training. Neural adaptations in preadolescents are cited as being similar to those in adults and include an increased frequency of motor-unit firing, improvements to motor-unit activation and synchronization, and the reduction of inhibitory signals on motor units from central nervous system pathways. Although muscle hypertrophy from training in children still remains a possibility, the majority of recent findings suggest that improvements in strength are independent of changes in muscle size.
The benefits of strength training in preadolescents deserve more attention and application. The preadolescent population can derive numerous benefits from strength training, which can outweigh any possible risks. These include, but are not limited to, improved muscular strength, endurance and flexibility; prevention of bone loss and osteoporosis; improved self-image, confidence and well-being; improved motor coordination and sports performance; decreased risk of injury; lowered blood pressure and cholesterol levels; weight maintenance; neuromuscular therapy and physical rehabilitation; promotion of lifetime physical activity; and improved aerobic capacity.
One of the most promising benefits of strength training may be increased bone mass. Bone mass, or bone density, continues to increase throughout growth and development, but a peak in bone mass, called the peak bone mineral density (PBMD), is reached at a young adult age. Attaining a higher peak bone mass as a young adult may delay the age at which a loss of bone from aging occurs. A loss of bone later in life, especially among menopausal women, can lead to osteoporosis, causing bones to become increasingly porous, brittle and fragile.
So, is it possible to influence bone mass during the first two decades of life to achieve a higher PBMD? Weight-bearing physical activity such as walking, jogging and strength training has been shown to have a positive effect on bone density by mechanically loading the skeleton. Though the precise amount and intensity of activity necessary to improve PBMD is uncertain, the importance of promoting load-bearing physical activities such as strength training for growing children is evident.
Although enhanced sports performance is another benefit of strength training, it has not been thoroughly studied, and it is questionable whether a young child should lift weights solely for the purpose of improving performance. The average young athlete is not competing at a high level, but rather developing basic skills necessary for future sports participation and success. Coaches must carefully weigh the level of competition, emotional maturity of the child and the possible benefit of decreased injury before recommending a strength-training program.
Children who strength train should follow a structured program that is taught and supervised by qualified instructors. Children are affected by interacting components such as musculoskeletal growth and sexual maturation. Therefore, borrowing exercise prescriptions from adult strength-training programs is inappropriate. For example, pushing to failure and performing forced repetitions or exaggerated eccentric contractions may be dangerous. Prepubescent children should not be expected to respond -- either physically or psychologically -- as adults do. Exercise prescriptions must be tailored to their individual needs, and program supervision must be exceptional.
Optimal prescription parameters, such as the number of sets and repetitions, have yet to be defined for the preadolescent population. It is recommended that children use the minimum dosage of training that produces beneficial improvements in strength and health without undue risk. Of all of the strength-training parameters, exercise intensity seems to be the key determinant of an effective program. Present guidelines suggest that intensity be moderate (approximately 10 to 15 repetitions) and that preadolescents avoid maximal lifts. A child should begin a program with one set of little or no weight and concentrate on learning proper form. Once proper technique is demonstrated, a resistance can be selected that allows approximately 10 repetitions to be performed. The number of repetitions is slowly increased until the maximal number (15) can be completed. Resistance is then advanced in small increments of one to three pounds. As the child advances, one to three sets can be performed as tolerated.
To achieve balance between agonist and antagonist muscle groups, eight to 10 exercises should be performed, with at least one for each major muscle group. The sequence of exercises should progress from larger muscle groups to smaller ones, and the frequency of training can start at two days per week and advance to three, as long as at least one day of rest is permitted between each training session. Workouts of approximately 30 minutes should be preceded by an appropriate warm-up and finished with a cool-down. Proper training techniques, such as lifting in a controlled manner, must be demonstrated and consistently emphasized throughout the program.
Safety considerations in any preadolescent physical activity program include proper instruction and close adult supervision. Improper instruction can lead to poor technique, which can cause acute and chronic injury. Weight-training literature points out that many injuries are the result of accidents (often from using excessive weight in power lifting) and unsupervised training.
To minimize the risk and maximize the benefits of strength training, health/fitness professionals and coaches must act responsibly by taking precautions before, during and after exercise sessions. It is imperative that they possess the background knowledge and experience to handle the preadolescent population. Instructors working with children should hold a degree in a health-related field such as exercise science or athletic training, as well as have current CPR and first aid certifications. There should be a small staff-to-participant ratio that is dependent on the number and ages of participants. For example, a class of more than 10 older children should have at least two instructors, with more staff added for larger groups.
Fallacies about strength training
Children should not lift weights before the age of 12. Twelve years of age is often used as a chronological marker for puberty since it is generally reached by age 12 for girls and age 14 for boys. Because of their immature skeletons, weight training was believed to place preadolescents at high risk for injury, and even possibly to interfere with normal growth. Therefore, many people recommended that children wait until puberty before participating in a strength-training program.
Chronological age, however, does not take into account the wide variation in the onset, progress and completion of biological growth and maturation. As a child enters the adolescent period, obvious changes in height, weight and sexual maturation occur. Skeletal maturation, though difficult to observe, is also occurring. All children proceed through growth and maturation in the same sequence, but a key difference is the rate of this process. There is such variation in the rate of physiological change that it becomes nearly impossible to compare preadolescents of similar chronological age without assessing their stage of maturation. Two 11-year-olds in the same activity class, for example, may be at very different degrees of growth and development. Although various methods of assessing maturity do exist, they are impractical for the fitness instructor or coach, and no single test gives a complete picture of individual growth and maturation.
Strength training will stunt growth in children and delay the age of menarche in girls. Recent studies indicate that growth and development is not affected -- either positively or negatively -- by a wide range of sports and training. A longitudinal British study called The Training of Young Athletes (TOYA) Study investigated the relationship between sports participation, growth and sexual maturation. Gymnasts, swimmers, and soccer and tennis players ages eight to 17 were followed over a three-year period. Results suggested that regular training does not adversely affect growth or sexual maturation, but rather that sport-specific selection occurs.
This acknowledged "pre-selection" for specific sports reflects a probable biologic and social selection among young athletes. For example, a basketball or volleyball coach may approach taller individuals to inquire about their interest in participation. Pre-selection for athletic success may favor either a late- or early-maturing child, depending on the specific size demands of a sport. Boys tend to compete in activities that require strength and power; therefore, early maturers who are taller and stronger may be at a performance advantage and are often more likely to participate.
Although the onset of menstruation is related to factors such as genetics and environment, the hypothesis that intensive training at a young age causes changes in biologic maturation has persisted. Based on this theory, many have suggested that young girls should not participate in sports. But sport-specific selection is also cited as a reason that young girls appear to be delayed in menarche. Activities that girls may be inclined to participate in, such as dance and gymnastics, may favor a late-maturing girl. Those who experience earlier changes in body composition and stature may be socialized away from sports that are biased toward a pre-menarcheal body type. There is currently no concrete data to implicate physical activity as a cause of delayed sexual maturity in girls.
Lifting weights will cause harm and injury to a child's bones, muscles and joints. In 1990, the American Academy of Pediatrics recommended that children and adolescents avoid weightlifting, powerlifting, bodybuilding, and lifting maximal amounts of weight until reaching Tanner Stage 5 of biological maturation. (Sexual or biological maturation can be assessed by a 5-point scale referred to as Tanner Staging, usually determined by a physician or nurse.) Styles of Olympic and powerlifting call for single-repetition maximum lifts, while bodybuilding is associated with high volumes of training to increase mass. These activities are competitive sports and should be highly discouraged in the growing child and adolescent. However, appropriate, safe and well-supervised strength-training programs in a school or health club that are intended to improve muscular strength and endurance can be an appropriate part of an overall physical activity program.
The concern about musculoskeletal injury and epiphyseal fracture may seem reasonable; a child's skeleton is maturing and damage to the bones and epiphyses, or growth plates, is potentially serious. Although the understanding of injury is somewhat limited by a lack of risk-factor studies, skeletal immaturity may be only one small component of weight-training injuries in children. Additional contributing factors to both acute and chronic injury include improper training techniques, lack of supervision, excessive loading, unsafe ballistic movements (e.g., clean and jerk), steroid abuse and repetitive abuse (overuse syndrome). Epiphyseal fractures have been reported in children and adolescents as a result of weight training, but are most often attributed to one or more of the preceding factors. It has been stated that growth plates are actually stronger in childhood than in adolescence, and that the concern over epiphyseal fracture may be overstated. More research is needed to determine the risk of injury from weight training, but current data suggest that the risk is no higher than that of participating in other sports. The risk of injury can be minimized with a properly designed training program and close adult supervision.
Conclusion
As the benefits of strength training become increasingly clear, it will undoubtedly become more popular among preadolescents. In 1996, the Centers for Disease Control reported that nearly half of young people ages 12 to 21 are not vigorously active, and that physical activity declines during the adolescent period. Perhaps the most valuable lesson to teach the youngest generation is how to develop a lifelong habit of physical activity. Promoting a healthy lifestyle, maintaining the habit of activity throughout the school years and preventing sedentary behaviors in adulthood will benefit not only today's children, but also future generations to come. FM
REFERENCES
1. American Academy of Pediatrics. Strength training, weight and power lifting, and bodybuilding by children and adolescents. Pediatrics 86(5): 801-803, 1990.
2. Armstrong, N., & J. Welsman. Young People and Physical Activity. Oxford University Press: N.Y., 1997.
3. Baxter-Jones, A.D.G., & P. Helms. Effects of training at a young age: A review of the Training of Young Athletes (TOYA) Study. Pediatric Exercise Science 8: 310-327, 1996.
4. Blimkie, C.J.R., & O. Bar-Or (eds.). New Horizons In Pediatric Exercise Science. Human Kinetics: Champaign, Ill., 1995.
5. Blimkie, C.J.R., & O. Bar-Or (eds.). Resistance training during preadolescence: Issues and controversies. Sports Medicine 15(6): 389-407, 1993.
6. Bryant, C., & J. Peterson. Not for adults only. Fitness Management 34-36, June 1996.
7. Brzycki, M. Youth Strength and Conditioning. Masters Press: Indianapolis, Ind., 1995.
8. Cahill, B. (ed.). Proceedings of the Conference on Strength Training and the Prepubescent. American Orthopaedic Society For Sports Medicine: Chicago, Ill., 1988.
9. Falk, B., & G. Tenenbaum. The effectiveness of resistance training in children: A meta-analysis. Sports Medicine 22(3): 176-186, 1996.
10. National Strength and Conditioning Association. Youth resistance training: Position statement paper and literature review. Strength and Conditioning 18(6): 62-75, 1996.
11. Ozmun, J., A. Mikesky & P. Surburg. Neuromuscular adaptations following prepubescent strength training. Medicine and Science in Sports and Exercise 26(4): 510-514, 1994.
12. Payne, V.G., J.R. Morrow, L. Johnson & S.N. Dalton. Resistance training in children and youth: A meta-analysis. Research Quarterly of Exercise and Sport 68(1): 80-88, 1997.
13. Reeves, R., E. Laskowski & J. Smith. Weight training injuries: Part 1: Diagnosing and managing acute conditions. The Physician and Sportsmedicine 26(2), 1998.
14. Reeves, R., E. Laskowski & J. Smith. Weight training injuries: Part 2: Diagnosing and managing chronic conditions. The Physician and Sportsmedicine 26(3), 1998.
15. Rowland, T. Exercise and Children's Health. Human Kinetics: Champaign, Ill., 1990.
16. U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Physical Activity and Health: A Report of The Surgeon General, 1996. Teaching Children Strength Training
* Request a complete physical exam and clearance form from all participants. Screen for any special health conditions and possible contraindications, such as chronic cardiovascular problems.
* Welcome only those participants who are emotionally mature enough to accept instruction and adhere to all policies and procedures. Have a definite course of action for disciplinary procedures and dismissal.
* Endorse strength training as one part of a total health and fitness program. Promote all components of a healthy lifestyle, including aerobic fitness, flexibility, proper nutrition, wellness and playtime.
* Evaluate equipment suitability for the age, size and maturity of the child using it. Inspect all equipment for safety prior to use. Make the most of available options, including dumbbells, resistance tubing, bands and body weight.
* Emphasize and enforce safety at all times. Never turn your back to participants. Be cognizant and pay close attention to each participant.
* Provide a thorough warm-up and cool-down for each exercise session.
* Allow adequate water breaks and suggest that children bring water bottles.
* Always accentuate proper technique such as a full range of motion, slow repetition speeds, proper body alignment and proper breathing.
* Clearly discourage competition. Remember that each child will progress at his or her own pace and that biological age is not an accurate predictor of readiness or performance.
* Incorporate weekly educational lessons about health, fitness and nutrition. Recommend quality resources including magazines, books and Websites to both parents and children.
* Encourage children to play an active role in their program. Use workout cards to monitor progress and solicit questions.
* Use a creative approach to design a variety of enjoyable workout programs and incentives (circuit training, small prizes and certificates for participation).
* Be a positive role model by encouraging and motivating children to strive for their personal best.