Strength and conditioning is an integral part of developing elite athletes. However, there is generally some question about the age appropriateness of strength and conditioning programs for junior athletes. The scientific research clearly tells us that regular participation in a properly supervised and appropriately structured strength and conditioning program can enhance physical performance and reduce injury risk in junior athletes.

It is important to note that youth athletes are a unique population. They are experiencing a range of physical, physiological and psychological changes as a result of growth and maturation (1). As such, they require specific and specialised training programs. Inappropriate training prescription may not only lead to reduced training adaptations but also increase injury risk.

When it comes to training junior female athletes. There are even more factors that need to be considered due to the unique changes that occur following maturation. Prior to maturation, there is little difference in motor performance, physical performance, muscular strength and landing mechanics between boys and girls. However, following maturation sex related differences become more evident with males consistently out performing females (2).

This is due to the ‘neuromuscular spurt’ evident in boys. The ‘neuromuscular spurt’ is the natural increases in muscle power, strength and coordination that occurs with maturation in boys (2). Unfortunately, this is not seen in girls and as a result we see plateaus and even decreases in muscular strength and power following maturation. In addition to this, in absence of the neuromuscular spurt, female athletes start to develop abnormal joint mechanics during landing, consequently increasing their overall injury risk. This is the reason you may notice decreased body awareness, strength and coordination as your daughter matures. Unfortunately, if this is NOT addressed it highly increases the chance of injury through adolescence.

The following 5 points highlight WHY strength and conditioning is vital for junior female athletes.

1. Strength and Conditioning acts as a Neuromuscular Spurt in Females.
A study showed that junior female athletes who participated in a well supervised and appropriately designed strength training program as they matured DID NOT develop the injury risk factors commonly seen following maturation in female athletes. Showing that participation in a strength training program may induce measures of the ‘neuromuscular spurt’ (2).

2. Strength and Conditioning Decreases ACL Injury Risk in Female Athletes.
An abundance of research has investigated the effectiveness of strength training interventions in the prevention of ACL injuries. On study showed 12-17 year old female football athletes were able to reduce ACL injury rate by 88% (3). Another study showed knee injury rates were 2.4-2.6 times higher in high school female athletes who DID NOT participate in a strength training program (4). These decreases in injury rates may be due to the increases in joint stability and adaptations that occur in the bones, tendons and ligaments following strength training.

3. Strength and Conditioning Improves Landing Mechanics in Female Athletes.
Following maturation, in the absence of the ‘neuromuscular spurt’ female athletes actually change the way they land from a jump. They begin to land with a more valgus knee (knocked knees) and a more extended leg. In combination, these 2 factors are a recipe for ACL injury. Studies have shown that strength training can improve knee joint biomechanics, one study showed high school female athletes were able to decrease valgus knee motion by 13% following only 7 weeks of strength training (5). Another study showed after 6 weeks of strength training high school female athletes landed with more knee flexion and significant decreases in valgus knee motion (6).

4. Strength and Conditioning Improves Performance in Female Athletes.
As previously pointed out in this article, following maturation female athletes tend to plateau or decline in physical performance measures. Participation in a structured and periodised strength and conditioning program has been shown to improve bench and squat 1RM, vertical jumping height, sprinting performance, single leg hop distance and VO2 max. Specifically, my research investigated physical performance effects following a strength training program in 11-14 year old netball athletes. Results indicated significant improvements in vertical jumping height, peak power, 20m sprinting speed and change of direction speed (7). Making strength and conditioning a must for any junior female athlete wanting to take their performance to the next level.

5. Strength and Conditioning Improves Psychological Wellbeing.
One of the reasons I am so passionate about females participating in strength training is due to the psychological benefits they gain from it. It gives them belief in themselves and feelings that they can accomplish anything and this begins to transfer into other aspects of their life. Research has shown that participation in a strength training program increases self-concept and self-perception. Improvements in self-perception were evident in female athletes after only 8 weeks of strength training (8). However, it is important to note that appropriate training prescription is vital for these benefits. As excessive training volume and load can lead to negative psychological effects.

There is a compelling body of scientific evidence that supports junior female athletes participating in strength and conditioning programs for numerous physical, physiological and psychological benefits. However, the key take away here is this participation needs to be appropriately designed and adequately supervised by qualified professionals. A qualified strength and conditioning coach with experience and knowledge relevant to coaching and training junior athletes, that understands their individual and unique needs.

Mandy x

References
1. Joyce, D & Lewindon (2014). High Performance Training for Sports.
2. Llyod R, Faigenbaum A, Stone M, Oliver J, Jefferys I, Moody J, Brewer C, Pierce K, McCambridge T, Howard R, Herrington L, Hainline B, Micheli LJ, Jaques R, Kraemer WJ, McBride M, Best TM, Chu DA, Alvar B, and Myer GD. Position statement on youth resistance training: the 2014 international consensus. British Journal Sports Medicine 48: 498-505, 2013.
3. Hägglund M, Atroshi I, Wagner P, and Waldén M. Superior compliance with a neuromuscular training programme is associated with fewer ACL injuries and fewer acute knee injuries in female adolescent football players: secondary analysis of an RCT. British Journal of Sports Medicine 47:974-979, 2013.
4. Hewett TE, Lindenfeld TN, Riccobene JV, and Noyes FR. The effect of neuromuscular training on the incidence of knee injury in female athletes. A prospective study. The American Journal of Sports Medicine 27: 699-706, 1999.
5. Myer GD, Ford KR, Palumbo J, and Hewett TE. Neuromuscular Training Improves Performance and Lower Extremity Biomechanics in Female Athletes. Journal of Strength & Conditioning Research 19: 51-60, 2005.
6. Chappell JD and Limpisvasti O. Effect of a neuromuscular training program on the kinetics and kinematics of jumping tasks. The American Journal of Sports Medicine 36: 1081-1086, 2008.
7. Hopper, A., Haff, E. E., Barley, O. R., Joyce, C., Lloyd, R. S., & Haff, G. G. (2017). Neuromuscular Training Improves Movement Competency and Physical Performance Measures in 11-13-Year-Old Female Netball Athletes. J Strength Cond Res, 31(5), 1165-1176.
8. Lubans DR, Aguiar EJ, Callister R. The effects of free weights and elastic tubing resistance training on physical self-perception in adolescents. Psychol Sport Exerc 2010;11:497–504