To Defend Against Injury Follow These 3 Steps
Written by Dr Craig Harrison
At just 12 years of age, Connor’s week was full of football commitments. On the weekend, he played a game for school and two for his local club. During the week, he trained every day after school and got up early on a Monday and Wednesday to do extra skill sessions.
But life wasn’t just about football. Connor loved all sports and when time allowed for it in his busy schedule, he would take up any opportunity that he could. The thing was, because Connor was incredibly dedicated to his efforts, each new endeavour would add more time and energy to his workload. School swimming sports, for example, led to Connor’s selection in the interschool zone competition, and thus more training to prepare.
The Adolescent Growth Spurt
During early adolescence, kids go through a period of accelerated growth. Stimulated by the onset of puberty, changes in the brain trigger the release of sex hormones in the body, which signals skeletal growth to take off. On average, research shows that the adolescent growth spurt begins between 9 and 10 years of age for girls and 11 and 12 years for boys, and, during this time, it’s not unusual for a young athlete to grow up to 12 cm per year.1
However, based on genetic, ethnicity and environmental differences, the initiation, duration and amount of growth vary considerably. For instance, a child who develops earlier on average than his peers (i.e., the early maturer), typically grows faster and over a shorter period of time. But not all kids grow the same. There can be up to a 5 year difference in when a child begins their growth spurt, which is why it’s normal for a team of 13 year-old athletes to be of completely different shapes and sizes.
A Storm of Growth
Connor was a little over 13 when a knee injury began disrupting his life. Worst during competition, intense pain just below his left kneecap forced him off the pitch, often before the whistle went for half time. Sometimes he wouldn’t even get past the warm up.
Connor was seeing a physio one a week for hands-on treatment and most evenings would spend time icing the pain and stretching out the muscles around his knee. But nothing really changed. The pain would return as soon as he did anything that required high-intensity running or quick, repetitive changes of direction.
The adolescence growth spurt is like a storm that hits with a series of powerful waves in an otherwise calm bay. Each wave builds momentum, peaks, and then loses energy over time. The biggest wave (i.e., the point at which a young athlete is growing the fastest) is called peak height velocity (PHV).
Bones are significantly more vulnerable during PHV. The elastic sections at the tip of the long bones in the body, called growth plates, are made up of soft cells, and allow the bones to lengthen during growth by rejuvenating over and over again. Once the body reaches maturity, these cells solidify into harder bone. Due to their ever-changing physical structure, growth plates are the weakest part of the bone during puberty and more easily damaged.
When growth plate injury does occur, it either happens acutely (sudden and severe in effect) or chronically (progressively worsens over time). Acute injuries occur for a numbers of reasons, including poor movement patterns, shortfalls in strength, or simply by accident. Chronic injuries, on the other hand, are mostly the result of repetitive loading to a part of the body that is not yet ready to handle it. If not managed correctly, growth pate injuries can adversely affect both development and future performance. At worst, they can negatively affect participation in sports and general well-being by causing long-term movement problems.
But it’s not just growth plate injuries causing concerns. Research conducted in New Zealand suggests that 60 percent of young athletes between the ages of 11 and 14 years suffer a sports-related injury each year. What’s more frightening is that 63 percent of all injuries in females and 42 percent in males are not accounted for in the statistics.
Predicting the Growth Storm
Growth charts have been used for years to track a newborn’s development. The information gathered about height and weight gives a parent a good idea of what to expect and if any intervention is required. Likewise, using methods discovered in recent research, predicting the point at which a young athlete enters and exists their growth spurt, as well as the duration of their most intense growth period (i.e., PHV), is possible. Once armed with this information, you can take the necessary steps to reduce the risk of an athlete getting injury and increase their performance outcomes.
The Development of Body Control
In the grasslands of the Serengeti, only the strong survive. When a giraffe is born, their skeletal system is highly developed and ready to go. It’s the result of a 15-month pregnancy during which energy is concentrated on the muscles. Then, straight after birth, the main goal of the infant is to get up and moving quickly to avoid being dinner a for lion or a pack of hungry hyenas. This rapid mastery of movement is fascinating to watch. It’s full of movement exploration, awkward falls and what appears on the surface to be a bunch of uncoordinated trial and error.
Adults typically find balance during movement using small, frequent adjustments in movement. However, when observing a child perform this task they typically use more wide-ranging, slower movements. This is because balance develops from larger, random sway motions during childhood to smoother, more controlled sway motions in adulthood. Just for fun, stop reading this now and go and stand on a straight line with the heel of your front foot and the second toe of your back foot touching. Close your eyes. How is your balance?
During the adolescent growth spurt, the length of a young athlete’s arms and legs relative to their trunk increases, which actually regresses the development of body control. This is known as adolescent awkwardness, or what some refer to as the baby giraffe effect. You may have seen it before? And just like a baby giraffe learning to walk, during adolescent awkwardness a young athlete needs to adjust to their changing body dimensions. The best way to do this is by (re)discovering movement.
The Importance of Movement Skill Training
Willem Teunissen, the former youth movement scientist at Ajax Football Club, introduced a maturity-matched “movement programme” specifically designed to help players transition through the adolescent growth spurt more safely and effectively. The programme included reductions in overall training load as well as fewer activities that demanded high amounts of rapid stopping (decelerating the body quickly puts significant stress on the body). It also placed more emphasis on activities that develop movement, strength and fitness.
Movement skill training is important for two reasons. First, it exposes young athletes to greater movement diversity. Performing a wide variety of athletic skills has been shown to limit repetitive movements that often lead to overuse injuries. Second, it builds muscular strength, which is essential for controlling the body safely during high-paced movements and radically reduces the likelihood of sustaining an acute injury such as an ACL rupture – one of the key ligaments that help stabilise your knee.
Adjusting Workload
Most sporting institutes, academies and representative programmes select during early adolescence. What this usually means for a young athlete is a significant increase in load right at the time of accelerated growth. To reduce injury risk, adjusting total workload is essential.2 Research shows that injuries are much more prevalent when the total amount of hours of sport each week exceeds an athlete’s age. The recommended weekly workload ceiling for Connor when he started getting knee pain was 13 hours. He was averaging 15.
The other key load variable is an athlete’s training to competition ratio. Compared to training, competition is higher paced and demand more overall intensity, which if a young athlete is not properly conditioned for, can result in injury. Accordingly, too much competition can be harmful.
To combat his chronic pain, Connor reduced his training to competition ratio from 2:1 to 3:1 and focused on the quality of his training rather than just playing more. This aligned with the latest scientific recommendations.
Defending Against Injury
When excessive load is added on top of a rapidly growing skeletal, injuries often result. To defend against this, follow these 3 steps:
- Forecast the growth storm – when you know what’s coming you can do what is needed to properly prepare
- Include activities that increase athleticism – a stronger, more resilient body handles the physical demands of sport much better
- Adjust the workload during periods of fast growth – focus on quality of development activities, not just doing more
Injury rates are increasing. It’s time you took a different approach to development that looks after the health of your young athletes. You might even find that performance increases as a result.
References
- Soliman, A., De Sanctis, V., Elalaily, R., & Bedair, S. (2014). Advances in pubertal growth and factors influencing it: Can we increase pubertal growth?. Indian Journal of Endocrinology and Metabolism, 18 (Suppl 1), S53–S62
- Jayanthi N, Schley S, Cumming SP, Myer GD, Saffel H, Hartwig T, Gabbett TJ. (2021). Developmental training model for the sport specialized youth athlete: A dynamic strategy for individualizing load-response during maturation. Sports Health.