Profile of a young athlete
Brian Mackenzie explores the physical development of young athletes and what we need to take into consideration when coaching them.
Young athletes are physically developing from early childhood to
late adolescence. This means they have different capabilities and
adaptations to exercise, and for this reason, young athlete training programs
should not be just scaled-down versions of adult training programs. The fastest
rate of growth occurs in the first two years. The growth rate then slows until
the adolescent spurt, when the growth rate increases again. The adolescent spurt
lasts approximately two years and takes place, on average, at 10 to 12 years for
girls and 12 to 14 years for boys. The growth rate then decreases until the full height is
reached. Muscle mass increases steadily until puberty, at which point boys show
faster muscle growth. The hormonal changes at puberty also affect body
composition in terms of fat.
- At birth, both boys and girls have around 10 to 12% body
fat.
- Pre-puberty, both girls and boys still have a similar 16 to 18%
body fat.
- Post-puberty, girls have around 25% body fat due to high serum
oestrogen, which causes the hips to widen and extra fat to be stored in the
same area.
- Post-puberty, boys have 12 to 14% body fat.
Most athletic females, post-puberty, tend to keep body fat at
around 18% (Wilmore & Costill, 1994). Any lower than 12% body fat for
females can be considered unhealthy in terms of maintaining bone density and
disrupting hormone levels, which may increase the risk of stress fractures.
Coaches need to make female athletes aware that until they are 19, they will
steadily gain muscle and so will naturally be gaining weight and that eating the right kinds of foods is the way to avoid unwanted weight gain.
Potential growth-related injuries
Bones develop from a cartilage growth plate, called epiphyseal plates, at each end of the bone shaft. These growth plates divide the calcified head of the bone (epiphysis) and the calcified shaft (diaphysis). The bone lengthens as cartilage is calcified into bone on the diaphysial border, thus lengthening the shaft. At the same time, cartilage continues to grow on the epiphyseal border, so the epiphyseal plates retain a constant width of cartilage throughout. Growth ends when the plate eventually calcifies.
The changes in the female body shape during the growth spurt have particular injury risks. The hips widen, placing the femur at a greater inward angle. During running or walking, this increased femur angle leads to a greater inward rotation at the knee and foot. This rotation can result in an injury called chondromalacia patella, which occurs when the kneecap does not run smoothly over the knee joint, and pain is caused at the front of the knee.
Appropriate preventive training to avoid chondromalacia patella would be to strengthen the vastus medialis muscle, the lower abdominals, obliques (side of stomach), hip abductors, and hip external rotator muscles. Traction injuries are another type of injury associated with bone growth. They are caused by repetitive loading while the tendon is sensitive to stress, as the bones and tendons are fusing.
Traction injuries occur at different sites at different
stages of growth.
- 10 to 13 years of age - at the heel (Sever's
disease).
- 12 to 16 years of age - at the knee (Osgood-Schlatter's
disease).
- Late adolescence - lower back and iliac pain.
The only cure for these traction injuries is rest.
Exercise
Exercise does not stunt or promote growth in terms of height, but it does thicken the bones by increasing mineral deposits (Wilmore & Costill, 1994). Growing bones are sensitive to stress, so repetitive loading should be avoided. The epiphyseal plate is susceptible to injury, and therefore, a fracture to the epiphyseal plate before full growth could be a serious injury as it could disrupt bone growth.
A more common kind of epiphyseal plate injury and the one coaches must take care not to cause is called epiphysitis. This is a repetitive strain injury that occurs when excessive loads are placed on the tendons that attach to the epiphysis, causing an inflammatory response. In extreme cases, this type of injury can result in a separation of the epiphysis from the epiphysial plate. The most common epiphysitis, called Little Leaguer's Elbow, occurs mostly in the USA among young baseball pitchers.
Strength
Strength increases with age because of body growth and the
development of the neuromuscular system. From research, Weltman et al. (1986)
carried out on the effects of resistance training on young athletes, it would
appear that strength improvements are possible. If coaches are to place young
athletes on strength training programs, then they must ensure that the young
athletes:
- Are properly taught (skill development)
- Undertake a well-controlled progressive program (planning)
- Joints are not subject to repetitive stresses (injury
prevention)
Code of conduct for coaches working with young
athletes
As coaches of young athletes, we need to ensure that every
child or young person who takes part in athletics can participate
in a fun and safe environment and be protected from neglect and physical,
sexual, and emotional abuse. To ensure that forms of abuse are prevented and to
help safeguard coaches who work with young athletes, the following guidelines
should be considered:
- Always be publicly open when working with children. Avoid
situations where you and an individual child are completely unobserved.
- If a performer needs to be touched, it should be
provided openly, and the performer should be asked first. Care is required, as it
is difficult to maintain hand positions when providing manual support if the
child is continually moving. Some parents are becoming increasingly sensitive
about touching children, and their views should always be carefully
considered.
- Where possible, parents should take responsibility for
their children in the changing rooms. If groups are to be supervised in changing
rooms, always ensure that adults work in pairs.
- Where mixed teams compete away from home, at least one
male adult and one female adult should always accompany them.
- Coaches must respect the rights, dignity, and worth of
all and treat everyone equally.
- Coaches must place the well-being and safety of the
performer above the development of performance. They should follow all
guidelines laid down by the sport's national governing body and be adequately
insured.
- Coaches should hold a current athletics leadership or coaching qualification in the activities which they direct or advocate, that are appropriate to the age, maturity, and ability of the performer.
- Coaches should always promote the positive aspects of
their sport (e.g. fair play) and never condone rule violations or the use of
prohibited substances.
- Coaches must consistently display high standards of
personal behaviour and appearance.
- Coaches should never overtly criticise athletes or use
sarcasm where it may cause the child to lose self-esteem or confidence.
It is recommended that you contact the national governing
body for your sport to obtain a copy of their codes of conduct for coaches
working with young athletes.
Aerobic and anaerobic development
The aerobic ability of young athletes can be developed, so it makes aerobic training worthwhile since it will improve their performance. Anaerobic training is of limited use to young athletes, as they possess little anaerobic capacity. Training for aerobic and anaerobic endurance is best left until the young athlete reaches adolescence. The development of sport-specific skills, along with agility and coordination, is an essential area to focus on when coaching young athletes.
Article Reference
This article first appeared in:
- MACKENZIE, B. (2003). Profile of a young athlete. Brian Mackenzie's Successful Coaching, (ISSN 1745-7513/ 4 / August), p. 1-2
Page Reference
If you quote information from this page in your work, then the reference for this page is:
- MACKENZIE, B. (2003) Profile of a young athlete [WWW] Available from: https://www.brianmac.co.uk/articles/scni4a1.htm [Accessed
About the Author
Brian Mackenzie was a British Athletics level 4 performance coach and a coach tutor/assessor. He has been coaching sprint, middle distance, and combined event athletes for the past 30+ years, and has 45+ years of experience as an endurance athlete.