Those who did the strength training saw a 6.2% increase in their bone mineral density, compared to a 1.4% in those who only did aerobic exercise.
For years there has been the myth circulating about the gym that young people should not lift weights. The source of this falsehood goes back to a study in Japan done in the early 1970s. Researchers found that child laborers were unusually short and attributed it the backbreaking physical labor these children had to perform. Somehow this research got extrapolated into the thought that young people should not lift weights or it will stunt their growth.
Part of the myth surrounding children and strength training is that it slows their bone development. This was proven wrong during a 10 month study of 9 and 10 year old girls. During this time the scientists measured bone mineral density in girls who did aerobic exercise along with strength training compared with girls who only participated in aerobic exercise. Those who did the strength training saw a 6.2% increase in their bone mineral density, compared to a 1.4% in those who only did aerobic exercise.
Researchers could not find any substantiation of damage to the bone growth plate or a stunting of growth.
There are countless studies that show that strength training in children does not harm bones or stunt growth. In fact, these studies not only conclude that strength training is safe, but that it is beneficial for youth. A study done by the Canadian Society for Exercise Physiology concluded that strength training in adolescents and youth not only increases their muscular strength, but their endurance as well. Additionally, they noted that these children also had increased bone density, improvement in their blood lipid profiles, better body composition, increased motor skills and coordination, and improved joint flexibility. Researchers could not find any substantiation of damage to the bone growth plate or a stunting of growth.
These findings by the Canadians matched the results of a study published by the University of Massachusetts, Boston in the United States . Both these studies noted that multiple health benefits can be obtained if the children are properly trained and certain guidelines are met.
These guidelines are echoed by the American Academy of Pediatricians. These guidelines include criteria such as:
- Youth weight training programs should be supervised by certified adults.
- Training time should not surpass a weekly maximum of 15 hours.
- Technique should be stressed, not the amount of resistance used.
- Conduct a 5-10 minute dynamic warm-up before lifting.
- Training sessions should occur only 2-3 times a week on non-consecutive days.
- Cool-down with low intensity activity and static stretching.
- Avoid body building, power lifting and maximal lifts.
- Low-resistance exercises are preferred.
- Strength training should be in conjunction with aerobic conditioning.
- Address all major muscle groups and complete range of motion.
Strength training is an excellent way to help fight the battle of obesity in children.
In addition to the numerous research studies available on the topic of strength training for youth, many government agencies have suggested children take part in strength training. The US Department of Health and Human Services recommends that youth participate in a minimum of 60 minutes each day of moderate to vigorous physical exercise. They also suggest strength training as part of the exercise during three days of the week .
Strength training is an excellent way to help fight the battle of obesity in children. Australian researchers demonstrated that eight weeks of resistance training can decrease body fat and increase lean muscle mass in children . Body fat was reduced by 2.6% and lean body mass increased by 5.3%.They measured other vital statics and found no decrease in height or bone mineral density.
The cited health benefits that result when children participate in strength training are numerous. These benefits include, but are not limited to:
- Decline in obesity and obesity related diseases.
- Prevent potential exercise related injury.
- Improvement of motor skills.
- Increased body strength.
- Maintain a healthy body weight.
- Decrease recovery time from injury.
- Better balance and coordination.
- Increased flexibility.
- Positive self-image and increased self-confidence.
- Good posture.
- Improved body composition and lean mass.
In summary, strength training by youth does not result in stunted growth.
Many parents want to know what age is appropriate for their child to begin strength training. It all depends on the maturity of the child because they have to be able to understand and follow instructions. For some children, it can be as young as 6, but for others they need to wait until they are older. There is no magic age, but should be left up to the discretion of the parent as to when they feel their child is mature enough. No matter what age your child is, it is imperative that the suggested guidelines are followed. Children should never be left alone in the gym. Strength training should not be the only form of exercise your child gets. It should always be done as part of their overall exercise regime which should also include aerobic exercise.
In summary, strength training by youth does not result in stunted growth. When performed under specific guidelines it can provide many positive health benefits for your child.
Behm, D., Faigenbaum, A., Faulk, B., & P., K. (2008). Canadian Society for Exercise Physiology position paper: resistance training in children and adolescents. The Canadian Society for Exercise Physiology , 547-61.
Faigenbaum, A. (2000). Strength training for children and adolescents. Clin Sports Med , 593-619.
McGuigan MR, T. M. (2009). Eight weeks of resistance training can significantly alter body composition in children who are overweight or obese. J Strength Cond Res. , 80-5.
Morris, F. e. (1997). Prospective ten-month exercise intervention in premenarcheal girls: positive effects on bone and lean mass. Journal of Bone and Mineral Research , 1453-1462.
Nettle H, S. E. (2011). Pediatric exercise: truth and/or consequences. Sports Med Arthrosc. , 75-80.
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