I keep seeing questions on various forums about children and running. Is it ok for them to run a 5k, 10k, half marathon, or even a marathon? Kids see their parents run and want to emulate them, but what distances are safe?

Unfortunately the research base for this question is sparse. What studies have been done are mostly related to the epidemiology of injuries in child runners – that is the features and rates of these injuries. In 2007 it was estimated that more than 12 million children aged 6-17 are involved in running for exercise. A study found that between 1994-2007, 225,344 children aged 6-17 were treated in the ER for running related injuries¹. In this study the overall injury rate at the ER was 30.7 per 100,000 children aged 6-17. More interestingly the rate was higher at 45.8 per 100,000 children aged 12-14. Also during the study period injury rates for these runners presenting to the ER increased by 34%.  The study was not able to prove why the rate had increased. Was the increase due to increased participation, or increased training loads? At this point we do not know. They do know, however, that 2/3 of injuries were sprains and strains of the lower extremity,1/3 involved a fall, and 1/2 occurred at school. The fall injuries were more serious and tended to be in younger runners. You can see the type of injuries related to fall and non-fall injuries in the pie charts below.

Injury associated with falls in runners aged 6-17

Injury not associated with falls in runners aged 6-17

These figures are only related to ER visits; I did not find a study looking at the overall child running injury rates, as this would be a very difficult study to do.

However, the study have just seen shows that there are different types of injury: those that are traumatic and those that are not. Outside of a traumatic injury, such as turning an ankle and spraining it, adolescent and pre-adolescent runners present with injuries due to overuse. A recent study² looking at high-school and collegiate athletes found that the sports with the highest number of overuse injuries is girls/boys cross country followed by girls/boys track and field. The injury rates were higher in females than males. Interestingly, the injury rate was three-times higher in college athletes than high-school athletes. The authors suggest that this may be due to poor habits learned in high school being amplified by higher level of training and competition. This suggests that quality training technique and habits developed as a child will help develop the same into college and hopefully later years – a lifelong pursuit.

Every child grows at a different and varying rate leading to what we term as growth spurts. As children grow, their bones, muscles, tendons all change length at different rates. This leads to a difference in the ratio between muscle-length and tension. This ratio is a key variable in overuse injuries as it affects loading of a joint. Coupled with this relationship are other features of child development; one research paper³ found that in adolescence body mechanisms such as visual, balance, and coordination are not fully mature. In fact, there are some studies that suggest some of these mechanisms regress in development before they continue to progress to maturity, although this is not fully understood. Combined with these issues surrounding development, there are other external variables that contribute to overuse injuries. Examples of these are early specialization (only doing one type of running/sport as the child’s exercises), and professionalization (child and parent taking it too seriously at too young an age; it should be fun if it is going to lead to lifelong participation which is great for health!).

There are many injuries, both traumatic and overuse, that only afflict children; below are a couple of examples (there are more!) of adolescent overuse running injuries that we see in sports medicine:

• Avulsion injuries occur when a tendon pulls away from bone, it is also called an avulsion fracture and there are many sites where there is potential for it to occur. An example is Osgood Schaltters, an evulsion of the patella tendon where it attaches at the shin bone (tibia). I actually had this as a child and it is very painful! As an uniformed teenager I continued to play and thankfully have only been left with a nice lump over the top of my tibia! However, it is possible for someone to have pain that persists past adolescence necessitating excision. It is also possible during adolescence for the avulsion fracture to displace.
• Growth plate injuries can occur with fracture extending through the plate or the slipping of the plate. These injuries can have longer-term effects and can affect the growth of the joint if not diagnosed and treated early, or even better prevented. An example of this is Slipped Capital Femoral Epiphysis (SCFE), where the growth plate in the hip (head of femur) slips. This is typically treated surgically with a long rehab process including a period of protected weight bearing. There are various extremes of this condition and also methods of fixation; there is the possibility of persisting pain, and early onset of arthritis.

Many of the injuries that can only affect children can have long-term effects on the child’s health, and their long term participation in sports. This can also lead to an increased utilization of health services which is disruptive for the child’s life, and to the parents’ work and budget.

This is complex, are there any guidelines?

When a guideline is produced by a group it should be based on evidence. The highest level of evidence are research papers called systematic reviews, the lowest is expert opinion. So in this case when specific research does not give a clear answer, guidelines are produced by groups of highly respected professionals (Surgeons, physicians, Physical Therapists, Athletic Trainers) based on their experience. Sometimes, these groups do not wish to provide a specific guideline when evidence is sparse. In this respect, the American Academy of Pediatrics simply states “if a child enjoys the sport and is asymptomatic no restrictions are placed on distance”. However other countries have created more specific guidelines from their groups of specialists. The Australian Sports Medicine Foundation recommends this:

Australian Sports Medicine Foundation guidelines for children running

They also recommended that those under 14 train 3 times a week, whereas those older should train 5 times a week. Sessions should not exceed 90min including warm up/down.

Mmmm, so what should my child do?

At the end of the day, with such varied guidelines and no clear evidence, the decision for a parent on running participation is a hard decision. The parent should take the above information and should combine it with advice from medical professionals. A pediatrician or pediatric orthopedic surgeon will be able to give some advice. These professionals are in a great position to tell you if your child is developing correctly and to order blood-work if there are physiological concerns. However, the ones I know will acknowledge that they are not afforded the time to conduct an examination that would detect muscle imbalances, which we have outlined as a cause of overuse injuries. Physical Therapists, however, have the skill set to augment the physician’s examination by providing a holistic examination of the musculoskeletal system. I have worked with too many children whose injuries could have been prevented and I feel that an injury prevention screening by a PT experienced with running injuries, including video running analysis, is important for your child. As well as identifying imbalances and teaching exercises that will correct them, we can also discuss appropriate warm-up and cool-down practices. Depending how your child grows, you may need to have some form of periodic examination, but it is my goal that you and your child should be able to learn how to manage their development, and I would expect with good warm-up, cool-down, and training practices, the odds that the imbalances will change dramatically are smaller.

If you are a parent, and want to protect the health of your child and also want them to enjoy a healthy lifetime pursuit, I would encourage you to consider our prevention and performance service.

References:

1. Mehl AJ, Nelson NG, Mckenzie LB. Running-related injuries in school-age children and adolescents treated in emergency departments from 1994 through 2007. Clin Pediatr (Phila). 2011;50(2):126-32.
2. Roos KG, Marshall SW, Kerr ZY, et al. Epidemiology of Overuse Injuries in Collegiate and High School Athletics in the United States. Am J Sports Med. 2015;
3. Quatman-yates CC, Quatman CE, Meszaros AJ, Paterno MV, Hewett TE. A systematic review of sensorimotor function during adolescence: a developmental stage of increased motor awkwardness?. Br J Sports Med. 2012;46(9):649-55.