| Our knowledge of the age and sex associated changes in strength
during childhood and adolescence is relatively limited compared to
other physiological parameters. However, those studies available on
the age and sex associated change in strength are relatively consistent,
especially for the lower limbs. Caution must be taken when transferring
this knowledge to other muscle joints as the development in strength
appears to be both muscle action and joint specific. Strength appears
to increase in both boys and girls until about the age of 14 y where
it begins to plateau in girls and a spurt is evident in boys. By 18
y there are few overlaps in strength between boys and girls. The exact
age in which sex differences become apparent appears to be both muscle
group and muscle action specific and there is a suggestion that sex
differences in upper body strength occur earlier than lower body strength.
What is less clear is the complex factors that contribute to the production
of strength during childhood and adolescence. There are few well controlled
longitudinal studies that have concurrently examined the influence
of known variables using appropriate statistical techniques. Most
studies have shown that maturation does not exert an independent effect
when other factors, such as stature and body mass are accounted for.
Also, the assumption that muscle cross-sectional area is the most
important parameter in strength production does not hold when examined
with other known variables. Consistently, stature appears to play
a key role in strength development and this may be attributed to the
strength spurt that has been linked to peak height velocity, and the
muscle moment arm. Advances in technology have provided us with more
accurate techniques to examine these explanatory variables but the
complex interaction of neural, mechanical and muscular remains to
be clearly identified from well controlled longitudinal studies.
KEY
WORDS: Strength, children, muscle size, technology.
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