Strength Training and Youth Athletes
In the past decade the amount of time our kids are outdoors playing has dramatically decreased. Owing to an increase in school work, increased ownership of handheld devices (tablets, iPads, mobile phones etc.), lack of open space and increased worry on behalf of the parents. 10-15 years ago children were climbing trees and playing street football, and nowadays they’re not, and as a result there are several implications for this. The biggest consequence of this is that their musculoskeletal system does not naturally develop, hence leading to a greater risk of injury during competitive sport. Now this doesn’t apply to everyone, there are some that are out 18 out of 24 hours of the day, 7 days a week, but that’s a discussion for another day.
FMS = fundamental movement skills, SSS = sport specific skills, PHV = peak height velocity, MC = metabolic conditioning.
The above figures are the Youth Physical Development models for both males (blue) and females (pink) (Lloyd and Oliver 2012). It was re-developed to be more comprehensive than previous versions. It presents a model of physical development showing when certain components of fitness can be more efficiently trained throughout an athlete’s development. Increasing font size indicates its sensitivity. Previously it was reported that there were ‘windows of opportunity’ for training specific components, and if you didn’t train during that window, then the window would shut and the young athlete’s potential would be capped. What this model presents to us is that there are ‘windows of opportunity’, but it is where an athlete will be MORE SENSITIVE to training adaptations, but also that they can be trained throughout their development. It’s also important to take note of the sex differences between males and females.
Now that you have a basic understanding of youth athletic development, we can start to talk about the why behind introducing it into our own coaching. Strength training is an umbrella term that can be used to described body weight training, resistance bands, barbells, dumbbells, medicine balls and weight machines. A lot of research has been done in this area and it supports the use of resistance training in children and adolescents. There are myriads of benefits to introducing strength training during pre-adolescence. Children are not simply ‘miniature adults’ and thus shouldn’t be treated as such. Strength training during pre-adolescence has the potential to increase muscular strength (Ramsay et al. 1990). As shown in the YPD model above, the training adaptations pre-PHV are predominantly neural changes occurring in the central nervous system. All muscles consist of motor units. These units consist of a motor neuron and the muscle fibres that it stimulates. Strength training increases the athlete’s ability to recruit more motor units and also increases the rate in which impulses reach these motor units from the brain (Kraemer et al. 1989). Strength training improves the athlete’s ability to synchronise motor units, recruiting more muscles simultaneously to improve strength, balance and general motor performance. Bone mineral density increases during strength training (Bass 2000). All these things combine to reduce risk of injury long term. As youth athletes move into adolescence, there are hormonal and maturational changes within the body. There is an increase in androgen concentrations (testosterone, growth hormone and insulin-like growth factor-1) and muscle fibres begin to differentiate between type-I (slow/endurance) and type II (fast/powerful). As a result of these hormonal changes, we see physical changes as well. There is an increase in power production from type-II muscle fibres leading to greater running velocity. There is an increase in metabolic rate from increased lean tissue mass, initiating better maintenance of body composition, also increasing psychological well-being in young athletes as well. So it raises the question, if strength training offers all these benefits, why isn’t there more being done to promote/integrate it into training or schools?
Up to now, we’ve briefly discussed youth athletic development, and barely scratched the surface in terms of why it’s a positive thing. The last thing I’d like to discuss is the effectiveness of injury prevention programmes. We know that children are less active nowadays. We know that their bodies aren’t physically able to keep up with the demands that are placed on them both through competitive sport and through engaging in multiple consecutive intensive training sessions during the week. Factors that influence injury risk are low fitness level, muscular imbalances and movement deficiencies among others. All this greatly increases the injury risk in the paediatric population, and as they say ‘prevention is better than cure’. While preventing injuries 100% is impossible, you can reduce the incidence and severity of non-contact injuries and reduce the time lost to playing. Let’s look at the evidence in favour of using strength training as an injury prevention tool. During a 4-year longitudinal study (study over a prolonged period of time looking at the same variables) on high-school age students in the USA, the introduction of a strength training programme reduced the incidence of injury by roughly half when comparing years 1 and 2 with 3 and 4* (Lehnhard et al. 1996). Similarly, a training programme utilising eccentric strength training, agility, jumping and balance was effective at reducing the injury rates by half in soccer players aged 13-18** (Emery and Meeuwisse 2010). These two examples, accompanied by the plethora of evidence which supports integrating some form of strength training during pre-adolescence for injury prevention and also improved neuromuscular performance as athletes move through adolescence towards adulthood, should provide enough food for thought for coaches. This is summed up perfectly by this infographic designed by @YLMSportScience (Myer et al. 2014).
Now that you have a basic understanding of youth athletic development, we can start to talk about the why behind introducing it into our own coaching. Strength training is an umbrella term that can be used to described body weight training, resistance bands, barbells, dumbbells, medicine balls and weight machines. A lot of research has been done in this area and it supports the use of resistance training in children and adolescents. There are myriads of benefits to introducing strength training during pre-adolescence. Children are not simply ‘miniature adults’ and thus shouldn’t be treated as such. Strength training during pre-adolescence has the potential to increase muscular strength (Ramsay et al. 1990). As shown in the YPD model above, the training adaptations pre-PHV are predominantly neural changes occurring in the central nervous system. All muscles consist of motor units. These units consist of a motor neuron and the muscle fibres that it stimulates. Strength training increases the athlete’s ability to recruit more motor units and also increases the rate in which impulses reach these motor units from the brain (Kraemer et al. 1989). Strength training improves the athlete’s ability to synchronise motor units, recruiting more muscles simultaneously to improve strength, balance and general motor performance. Bone mineral density increases during strength training (Bass 2000). All these things combine to reduce risk of injury long term. As youth athletes move into adolescence, there are hormonal and maturational changes within the body. There is an increase in androgen concentrations (testosterone, growth hormone and insulin-like growth factor-1) and muscle fibres begin to differentiate between type-I (slow/endurance) and type II (fast/powerful). As a result of these hormonal changes, we see physical changes as well. There is an increase in power production from type-II muscle fibres leading to greater running velocity. There is an increase in metabolic rate from increased lean tissue mass, initiating better maintenance of body composition, also increasing psychological well-being in young athletes as well. So it raises the question, if strength training offers all these benefits, why isn’t there more being done to promote/integrate it into training or schools?
Up to now, we’ve briefly discussed youth athletic development, and barely scratched the surface in terms of why it’s a positive thing. The last thing I’d like to discuss is the effectiveness of injury prevention programmes. We know that children are less active nowadays. We know that their bodies aren’t physically able to keep up with the demands that are placed on them both through competitive sport and through engaging in multiple consecutive intensive training sessions during the week. Factors that influence injury risk are low fitness level, muscular imbalances and movement deficiencies among others. All this greatly increases the injury risk in the paediatric population, and as they say ‘prevention is better than cure’. While preventing injuries 100% is impossible, you can reduce the incidence and severity of non-contact injuries and reduce the time lost to playing. Let’s look at the evidence in favour of using strength training as an injury prevention tool. During a 4-year longitudinal study (study over a prolonged period of time looking at the same variables) on high-school age students in the USA, the introduction of a strength training programme reduced the incidence of injury by roughly half when comparing years 1 and 2 with 3 and 4* (Lehnhard et al. 1996). Similarly, a training programme utilising eccentric strength training, agility, jumping and balance was effective at reducing the injury rates by half in soccer players aged 13-18** (Emery and Meeuwisse 2010). These two examples, accompanied by the plethora of evidence which supports integrating some form of strength training during pre-adolescence for injury prevention and also improved neuromuscular performance as athletes move through adolescence towards adulthood, should provide enough food for thought for coaches. This is summed up perfectly by this infographic designed by @YLMSportScience (Myer et al. 2014).
*Intervention introduced during the off-season period between seasons 2 and 3.
**Used a training group who completed the intervention and a control group who did not.
**Used a training group who completed the intervention and a control group who did not.
Hopefully this has gone some way to shed some light on strength and conditioning in youth athletes. Strength training can be implemented with teams/players even pre-adolescence. Provided it is safe and supervised by a professional who is educated, there are countless benefits.
This article is an introduction to a broad range of topics, topics which will be discussed further in the future. The main aim of these is to educate all of those who are involved in the development of young children to improve their quality of health and fitness, and athletes aspiring to make a career out of their chosen sport. This information is relevant regardless of what sport you are involved in.
Take Home Message:
This article is an introduction to a broad range of topics, topics which will be discussed further in the future. The main aim of these is to educate all of those who are involved in the development of young children to improve their quality of health and fitness, and athletes aspiring to make a career out of their chosen sport. This information is relevant regardless of what sport you are involved in.
Take Home Message:
- Children can engage in strength training during pre-adolescence, provided they can adequately follow instruction.
- All strength training must be safe and supervised at all times.
- As coaches we must create positive associations with exercise and foster good habits as early as we can.
- Multi-faceted programmes that include elements of increasing strength, improving balance, enhancing movement will all improve a child’s functional capabilities and influence future health.
Reference List:
- Bass, S. L. (2000) 'The prepubertal years', Sports Medicine, 30(2), 73-78.
- Emery, C. and Meeuwisse, W. (2010) 'The effectiveness of a neuromuscular prevention strategy to reduce injuries in youth soccer: a cluster-randomised controlled trial', British Journal of Sports Medicine, 44(8), 555-562.
- Kraemer, W. J., Fry, A. C., Frykman, P. N., Conroy, B. and Hoffman, J. (1989) 'Resistance training and youth'.
- Lehnhard, R. A., Lehnhard, H. R., Young, R. and Butterfield, S. A. (1996) 'Monitoring Injuries on a College Soccer Team: The Effect of Strength Training', The Journal of Strength & Conditioning Research, 10(2), 115-119.
- Lloyd, R. S. and Oliver, J. L. (2012) 'The youth physical development model: A new approach to long-term athletic development', Strength & Conditioning Journal, 34(3), 61-72.
- Myer, G. D., Faigenbaum, A. D., Ford, K. R., Best, T. M., Bergeron, M. F. and Hewett, T. E. (2011) 'When to initiate integrative neuromuscular training to reduce sports-related injuries in youth?', Current sports medicine reports, 10(3), 155.
- Ramsay, J. A., Blimkie, C., Smith, K., Garner, S., MacDougall, J. D. and Sale, D. G. (1990) 'Strength training effects in prepubescent boys', Medicine and science in sports and exercise, 22(5), 605-614.
RSS Feed