Transcript Document

ADOLESCENT GROWTH AND
MOTOR DEVELOPMENT
Larry D. Isaacs
§10.1 DEFINING ADOLESCENCE
 Most frequently, adolescence has been defined as a
transitional period between childhood and adulthood.
 According to the World Health Organization,
adolescence would be expected to occur between the
chronological ages of 10 to 18 years.
 A more realistic global chronological age range
would be in the vicinity of 8 to 19 years of age for
girls and between 10 to 21 years of age for boys.
§10.2 THE ENDOCRINE SYSTEM:
HORMONAL INFLUENCES ON
AGENTS OF BIOLOGICAL CHANGE
 The hallmark of pubertal initiation is the
appearance of gonadotropin releasing
hormone (GRH)
 It is the hypothalamus - pituitary - gonadal
axis which is responsible for most of the
biological hallmarks associated with
adolescence.
§10.3 SOMATIC PATTERNS OF CHANGE IN
BODY SIZE AND IMPLICATION FOR MOTOR
PERFORMANCE
Stature
 One of the most profound somatic changes to
occur during adolescence is the rapid
acceleration in stature.
 Brought about by the many hormonal changes
described earlier, this 2.5- to 3-years of rapid
growth is referred to as the adolescent growth
spurt.
 The term adolescent awkwardness has been
used to refer to a period during the growth
spurt
 peak height velocity (PHV); maximum rate
of growth in height that is accompanied by a
temporary disruption in motor performance
Weight
 Adolescence can bring about dramatic
increases in body weight .
 During the first 3 years of this period, boys
add about 20 kilograms to their body weight
and girls add about16 kilograms,
 Body mass index (BMI) :
 This measure is valuable because it is related to body
fatness and future health risks, including increased
incidence of cardiovascular disease, diabetes,
hypertension , hypercholesterolemia, and certain
cancers .
 BMI cannot be used to determine percentage of body
fat.
Body Proportions
During adolescence not all body segments growth at the
same velocity nor do they grow in an absolute comparative
manor.

The comparison of biacromial breadth (shoulder width)
to bicristal breadth (hip width).

Changes in sitting height (trunk length) as a ratio with
stature

Arm length also appears to influence motor performance.
Muscular Strength Development
 prior to puberty boys are about 10 percent
stronger than girls 。
 Gender differences in muscular strength
become most apparent after puberty
 During this time of development, boys
become leaner and young girls begin to
develop more body fat.
§10.4 DETERMINING DEVELOPMENTAL
AGE AND MATURATIONAL STATUS
Developmental age, however, is by far a
better indicator of maturity than is
chronological age.
A set of predictable physiological parameters
 Skeletal age -the most widely accepted
assessment procedure for determining stage
of maturation
 Age of menarche is an important event useful
for estimating level of maturation, even
though the event does not generally occur
until relatively late in puberty.
 Genitalia development is an ancillary method
for rating level of biological maturation.
Maturation: Interrelationship with Motor
Performance
 Researchers recognize that physically advanced
people generally perform selected motor tasks more
proficiently than their less mature counterparts.
 Early maturation, with its concomitant size
and strength advantages, constitutes an asset
positively associated with success in several
sports
 Once the late-maturing person has reached a
state of postpubescent development, he is
generally larger and has more athletic success
simply because he has had a longer growth
period.