Sports Coach Logo Sports Coach Training Principles Fitness Components


Flexibility - Are we hurting kids?

Brian J Grasso reviews the type of flexibility training one should perform with young athletes.

Flexibility remains a mysterious avenue within the sports industry, cluttered with myths, half-truths, and opinions. Questions purvey in many trainers', coaches', and parents' minds as to the type of flexibility training one should perform, when they should perform it, and for how long. Of critical importance to this problem is the young athlete, and how flexibility training should be applied to this demographic. This article will not answer every question you may have, but it will shed some light on a few key points.

Assessment of flexibility

The scope of confusion regarding flexibility can be seen when considering the assessment tools most used to test one's suppleness. The standard 'sit & reach' test is most often incorporated into pre-training assessments as the 'flexibility test'. In fairness, many coaches and trainers I have worked with cite the fact that the 'sit & reach' is an indirect assessment of flexibility at best and does not give a truly accurate picture as to the 'global' suppleness an athlete may possess considering that flexibility is joint-specific. Also, it does not allow us to assess any dynamic qualities, which is vital because static flexibility is quite different from dynamic flexibility, and dynamic flexibility is critically more important in sport.

Strength training

The degree of flexibility a joint exhibits is not entirely determined by the tightness or pliancy of the muscles which act on that joint. While the elasticity of the muscle is a key component of flexibility, so is the elasticity of the corresponding ligaments and even the emotional state of the individual. Additionally, the physical length of a muscle can play a very large role in determining the flexibility or range of movement (ROM) of a joint. Muscle length is determined by genetics but can also be positively influenced by strength training. This certainly contradicts a common myth that strength or resistance training INHIBITS flexibility. Furthermore, as the elasticity of a muscle reduces with age (which we accept as true), strength training can also positively influence this concern. Yes... Strength training has a positive impact on flexibility and suppleness! When working with younger athletes, static stretching habits can increase the length of a ligament and lead to joint instability. This can lead to poor posture and increased dependence on muscles for joint stability. Strength and flexibility (through full ROM) must work hand-in-hand to ensure optimal development and decreased injury occurrence.

Flexibility training

In terms of young athletes, flexibility develops in correspondence with growth. In terms of training, type, frequency, and duration also change with age.

Ages 6 to 10

Hip and shoulder mobility declines, resulting in the need for dynamic ROM exercises within these two joints (multidirectional raises and rotations). Maximum flexibility of the spine is reached by the age of 8 or 9 - increases beyond normal ROM can be made but is unnecessary and considered potentially harmful. Within this age group, STATIC STRETCHING SHOULD BE AVOIDED. Excitement within the nervous system is much more pronounced than inhibition, which means that kids this age cannot truly execute a held stretch. They cannot gain the appropriate feedback from their body needed to ensure the safety and optimal effectiveness of the stretch. Additionally, Isometric stretches (as found in Yoga), should also be avoided completely in this age category. These kinds of stretches may increase the resting tone of a muscle which can negatively affect movement skills and coordination. Remember - Fitness fads come and go, but the critical science of athletic development and human physiology is what it is. Yoga has its place to be sure (although I know many skeptics who disagree with that), but coordination and movement MUST dominate this age bracket.

Ages 10 to 13

Children incur gains of body mass at a quicker rate than gains in height at this age, which leads to an increase in strength. Flexibility training should intensify in this age category. Increases in strength and changes in body mass can combine and lead to poor biomechanical habits - most critically in not using full ROM during exercise. Ensure that kids incorporate full ROM and dynamic exercises into their training.

Ages 13 to 15

Height can increase as much as one inch per month during the growth spurt. Muscles and supporting connective tissue do not grow as quickly as bone, which can result in general pain throughout the body. Flexibility training can and should target the areas most prone to pain - this would include quadriceps, hamstrings, and muscles of the lower lumbar spine specifically. Poor posture, reduced movement skills, and injury are all potential concerns of rapid growth but can be limited with appropriate flexibility habits.

Ages 15+

Now is the time to start adding sport-specific means of flexibility training into an athlete's routine. Flexibility, especially with young athletes, is not at all just a matter of 'stretching out' before or after practice.

I hope this article has shed some light on a few things for you!

Article Reference

This article first appeared in:

  • GRASSO, B. (2004) Flexibility - Are we hurting kids? Brian Mackenzie's Successful Coaching, (ISSN 1745-7513/ 17 / November), p. 5

Page Reference

If you quote information from this page in your work, then the reference for this page is:

  • GRASSO, B. (2004) Flexibility - Are we hurting kids? [WWW] Available from: [Accessed

About the Author

Brian Grasso is the President of Developing Athletics which is a company dedicated to educating coaches, parents, and youth sporting officials throughout the world on the concepts of athletic development. Brian can be contacted through his website at