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Vol 9, No 1, January/February 2001
29
Because of the increasing demands
for performance and the decreasing
ages of participation and peak per-
formance, young athletes are con-
tinually being asked to perform at
higher levels and to improve at a
quicker pace than ever before. As
the demands increase, the athletic
community has been asked to sup-
ply the means to increase athletic
performance, and the medical com-
munity has been asked to validate
the safety of these methods.
Strength training has become one
of the most popular and rapidly
evolving modes of enhancing ath-
letic performance. Although initial-
ly limited to those sports thought to
require strength for optimal perfor-
mance, such as football and rugby,
some form of strength training has
now been adopted in virtually every
sports activity.
It is commonplace for adult ath-
letes, both male and female, to par-
ticipate in some form of strength
training to enhance performance
and endurance and to reduce the
risk of injury. While the effective-

ness, risks, and methods of training
for the adult population have been
extensively studied,
1,2
the role of
strength training for children and
adolescents remains a topic of con-
troversy and often heated debate.
3-5
A number of important questions
have been asked. Can strength
training increase the muscular
strength in young athletes? Is
strength training safe? Can strength
training result in increased athletic
performance?
The initial controversy surround-
ing strength training for the young
athlete evolved from unfounded
statements and three misconcep-
tions regarding the risks and poten-
tial benefits to the athlete. The first
misconception is that the prepubes-
cent athlete cannot benefit from
strength training because of insuffi-
cient circulating levels of andro-
gens.
6
However, this has been dis-
proved over the past decade, as

research has documented that young
athletes do in fact gain strength
with a properly planned and super-
vised training regimen.
4,7-13
The second misconception is that
athletes participating in strength
training lose both the flexibility and
the range of motion necessary for
optimal performance in their chosen
sport. This has also been refuted by
recent studies, with some research-
ers reporting increased flexibility
when flexibility training was incor-
porated into a training regimen.
10
The third misconception is that
strength training is dangerous and
exposes the young athlete to unnec-
essary risk of injury. This particu-
lar question remains a cause for
concern for parents and general
physicians. The persistence of this
concern is largely due to the inap-
propriate comparison of injury
rates with different modes of train-
Dr. Guy is Fellow in Sportsmedicine, Boston
Children’s Hospital, Boston, Mass. Dr.
Micheli is Director, Division of Sports
Medicine, Boston Children’s Hospital; and

Associate Clinical Professor of Orthopaedic
Surgery, Harvard Medical School, Boston.
Reprint requests: Dr. Micheli, Boston
Children’s Hospital, 319 Longwood Avenue,
Boston, MA 02115.
Copyright 2001 by the American Academy of
Orthopaedic Surgeons.
Abstract
Strength, or resistance, training for young athletes has become one of the most
popular and rapidly evolving modes of enhancing athletic performance. Early
studies questioned both the safety and the effectiveness of strength training for
young athletes, but current evidence indicates that both children and adoles-
cents can increase muscular strength as a consequence of strength training.
This increase in strength is largely related to the intensity and volume of load-
ing and appears to be the result of increased neuromuscular activation and coor-
dination, rather than muscle hypertrophy. Training-induced strength gains are
largely reversible when the training is discontinued. There is no current evi-
dence to support the misconceptions that children need androgens for strength
gain or lose flexibility with training. Given proper supervision and appropriate
program design, young athletes participating in resistance training can increase
muscular strength and do not appear to be at any greater risk of injury than
young athletes who have not undergone such training.
J Am Acad Orthop Surg 2001;9:29-36
Strength Training for Children and Adolescents
Jeffrey A. Guy, MD, and Lyle J. Micheli, MD
Strength Training for Children and Adolescents
Journal of the American Academy of Orthopaedic Surgeons
30
ing, such as weight training, resis-
tance training, and power lifting.

Injury rates with these modes of
training can vary greatly, and ex-
trapolation from one to another can
be misleading.
The literature in recent years has
helped dispel some misconceptions
about strength training for children
and adolescents. Unfortunately,
however, information from the med-
ical community on these topics may
appear to be inconsistent, depending
on the experience of the practitioner
and his or her knowledge of recent
studies on strength training. Not
surprisingly, parents, coaches, and
trainers remain confused and uncer-
tain about strength training and
often refrain from its use.
Definitions
The term “strength training” is
defined as the use of progressive
resistive methods to increase one’s
ability to exert or resist force.
4
The
term “resistance training” may also
be used in the same context and is
often considered synonymous.
This type of training is both con-
trolled and progressive, often utiliz-

ing various modalities, such as free
weights, individual body weight,
hydraulics, and elastic bands, to
name a few. To be successful, a par-
ticular training regimen must be
individualized and must involve a
timely progression in intensity,
thereby stimulating strength gains
that are greater than those associ-
ated with normal growth and de-
velopment.
One particular area of confusion
is in the use of the terms “strength
training” and “resistance training”
in relation to the terms “weight lift-
ing” and “power lifting.” The latter
terms should be used only to de-
scribe techniques of training at high
intensities with the goal being to lift
maximal amounts of weights, often
in competition.
When reviewing the literature,
the age group involved in discus-
sion can be particularly confusing.
For the purposes of this review, the
definitions by Faigenbaum and
Bradley
4
will be utilized. The terms
“prepubescent” and “child” refer to

girls and boys prior to the develop-
ment of secondary sex characteris-
tics, roughly defined as up to the
age of 11 years for girls and up to
age 13 for boys. The terms “pubes-
cent” and “adolescent” are applied
to girls aged 12 to 18 and boys aged
14 to 18. The term “young athlete”
is a more comprehensive term and
will be used when discussion in-
cludes both the prepubescent and
the pubescent athlete.
Effectiveness of Strength
Training for Young
Athletes
The topic of strength training by
adult athletes has been the subject
of extensive research.
14
However,
the role of strength training for the
young athlete remains controversial
despite recent studies at a number
of centers.
During the 1970s, there were few
studies available. As a result, many
clinicians discouraged strength
training for children. It was felt
that prepubescent children were
incapable of developing much

strength and that physical weak-
ness after puberty is merely the
result of insufficient physical exer-
tion.
15
This stance was reflected in
a 1983 position paper of the Ameri-
can Academy of Pediatrics in which
it was stated that “prepubertal boys
do not significantly improve strength
or increase muscle mass in a weight
training program because of insuffi-
cient circulating androgens.”
6
Furthermore, several early stud-
ies failed to demonstrate increased
strength in children engaged in
strength-training programs.
16,17
In
1978, Vrijens
16
reported no strength
gains in a study of 10- to 17-year-
old boys undergoing training ses-
sions three times a week for a total
of 8 weeks’ duration. Of interest,
the training program involved low
resistance and employed only one
set of exercises per session. In a

similar study, Docherty et al
17
found that 12-year-old boys did not
benefit from strength training fol-
lowing their competitive season.
The frequency of training was three
times weekly for a total of 4 to 6
weeks. However, both the low
intensity of two sets per session and
the short duration of the study may
have compromised the results of
the study.
These studies have been cited in
the literature as proof that strength
training is ineffective for young ath-
letes; however, careful evaluation
suggests that these results may
have been flawed by methodologic
shortcomings. The nature of con-
trol groups is important because as
children continue to grow, a prepu-
bescent athlete may in fact develop
an increase in strength from normal
growth alone, thus confounding
any benefit from a training pro-
gram. In addition, the training pro-
gram itself may not provide the
intensity, frequency, or length of
training necessary to allow the
prepubescent athlete to develop

enough muscular strength to over-
come differences observed with
normal growth alone.
The past 15 years has seen a pro-
gressive and increased interest in
the topic of strength training, and a
number of controlled studies have
examined the benefits and risks of
youth strength training. One of the
earliest clinical studies supporting
strength training for prepubescent
children was by Sewall and Mich-
eli.
10
Eighteen prepubescent boys
and girls participated in pneumatic
resistance training for three 30-
minute sessions per week for a total
of 9 weeks. The children involved
in training had a statistically signif-
Jeffrey A. Guy, MD, and Lyle J. Micheli, MD
Vol 9, No 1, January/February 2001
31
icant (P<0.05) mean increase in
strength of 42%, compared with a
9% increase for control subjects.
The study also showed that, even
over a 9-week period, prepubescent
children have a baseline increase in
strength due to normal growth and

maturation.
Similar findings were demon-
strated by Weltman et al,
18
who
examined the effects of hydraulic
strength training on prepubertal
boys. Twenty-six boys participated
in a strength training program three
times a week for 14 weeks, and dif-
ferences in isokinetic strength for
flexion and extension at the knee
and elbow joints were evaluated.
Compared with an untrained con-
trol group, subjects involved in
training had an increase in strength
of up to 36% for concentric work
and an increase in torque of up to
45% for all eight motions tested
(P<0.05). The findings in this study
suggest that short-term, supervised
concentric strength training with
use of hydraulic resistance is both
effective and safe for prepubertal
boys, with no injuries sustained
while training.
As further evidence in support of
strength training for prepubescent
children accumulated, researchers
began to manipulate training regi-

men variables (e.g., frequency, in-
tensity of exercise, and duration of
training) in search of an optimal pro-
gram. Because overuse injuries are
not uncommon in the pediatric pop-
ulation,
19,20
Faigenbaum et al
7
investi-
gated the effects of a shortened fre-
quency of training (twice a week)
while maintaining a high level of in-
tensity. In an 8-week study, prepu-
bescent subjects underwent a twice-
weekly training schedule based on an
individual’s 10-repetition-maximum
(10-RM) strength (i.e., the maximum
weight that could be lifted ten times
with good form). The prepubescent
children were found to have a mean
increase of 74% in 10-RM strength
values compared with nontrained
control subjects. Faigenbaum et al
8
found similar results in prepubescent
subjects in a 1996 study: a mean
increase of 53% in leg extension and a
41% mean increase in chest-press val-
ues after 8 weeks of strength training.

Thus, at a given intensity, twice-
weekly training programs appear to
increase strength in children to a
level equivalent to that found with
schedules requiring participation
three times per week.
Taking into consideration the
number of variables involved in
determining the effectiveness of
resistance training, Falk and Tenen-
baum
5
conducted a meta-analysis
of nine studies demonstrating in-
creased strength. All children in the
studies were under the age of 13
years. In the combined studies, the
resistance training group had a
71.6% increase in strength over the
control group. There was no ad-
vantage at any particular age, and
there were no differences between
the sexes.
Thus, current evidence indicates
that resistance training can result in
marked strength gains in the pre-
pubescent child. While the ultimate
duration and intensity continue to be
debated, children develop strength
gains with workouts as infrequent

as twice weekly. At this time, there
do not appear to be any sex- or age-
related differences.
Physiologic Mechanisms
for Strength Development
Although the literature supports
the contention that children may
demonstrate strength gains with a
proper training regimen, it is more
difficult to define how and why this
occurs and what the underlying
mechanisms are. Numerous fac-
tors, including muscle hypertrophy,
increase in muscle cross-sectional
area, motor-unit coordination, cen-
tral nervous system activation, and
psychological drive, may all con-
tribute to increases in strength.
These factors have been extensively
studied in adults, but few studies
have evaluated the underlying
mechanism of strength gains in
children.
In an attempt to determine the
contribution of muscle hypertrophy
to increased strength, several re-
searchers have included morpho-
logic variables in their evaluation of
strength changes.
7,9,18,21-23

Weltman
et al
18
found little or no change in
anthropometric and body composi-
tion measures in prepubescent boys
over a 14-week training period. No
statistically significant differences
were found in body circumference
or skin-fold measurements. Body
density as measured by hydrostatic
weighing was also unchanged.
Ramsay et al
9
found no statistically
significant changes in anthropomet-
ric indicators in prepubescent boys
over a 20-week resistance training
period. No changes were seen in
the cross-sectional area of either the
midportion of the upper arm or the
midthigh as measured with com-
puted tomography.
Because prepubescent children
lack circulating androgens, it is not
surprising that strength gains seen
in resistance training are not associ-
ated with the muscle hypertrophy
seen in the adult population (at least
not in short-term studies). Neural

adaptations have been implicated
by some as primarily responsible
for strength gains.
9,22
Ozmun et al
22
addressed this issue in a study of
the effects of thrice-weekly biceps
curls on prepubescent children over
the course of 8 weeks. Significant
isotonic and isokinetic strength in-
creases were found in the trained
group (22.6% and 27.8%, respective-
ly), with no changes in either skin-
fold or arm-circumference measure-
ments. While these findings confirm
that strength gains are not the result
of muscle hypertrophy, the increased
electromyographic measurements
(17% greater amplitude in the trained
Strength Training for Children and Adolescents
Journal of the American Academy of Orthopaedic Surgeons
32
group) suggest that the early gains
in strength seen in prepubescent
children are due in part to increased
muscle activation.
Only one other study has ad-
dressed the neural adaptations in
strength training in children.

Blimkie et al,
12
looking at isotonic
strength changes in prepubescent
children, found a significant (P<
0.05) increase in strength over a 10-
week training period. Although
there were no differences in muscle
cross-sectional area, an increasing
trend in motor unit activation was
noted, as determined by interpolar
twitch. It has also been suggested
that intrinsic muscle adaptations,
increased motor activation, im-
proved motor skill performance,
and coordination of the involved
muscle groups may all play a role
in the muscle strength seen with
resistance training.
9
Although at this time it may be
difficult to separate out the contri-
butions and relative importance of
each variable, it appears that neu-
romuscular activation, motor coor-
dination, and intrinsic muscular
adaptations all contribute to the
increased strength seen in prepu-
bescent athletes undergoing resis-
tance training. Similar mechanisms

are found in adolescents and
young adults,
14
but strength gains
seen in prepubescent children ap-
pear to be largely independent of
muscle size. Not surprisingly, the
training-induced gains in strength
seen in postpubertal boys are
accompanied by increased cross-
sectional area of muscle.
16
Persistence of Training-
Induced Gains
The removal of stimulus, or “de-
training,” is defined as the tempo-
rary or permanent reduction or with-
drawal of a training stimulus, which
may result in the loss of physiologic
and anatomic adaptations, as well as
a decrease in athletic performance.
8
There are few studies of detraining
in adults and even fewer in the pre-
pubescent population. Furthermore,
attempts to evaluate the persistence
of resistance-induced strength gains
in prepubescent subjects after with-
drawal of a training stimulus may
be confounded by the concomitant

growth-related strength increases.
24
In a study of detraining in pre-
pubescent children, Sewall and
Micheli
10
suggested that the loss of
strength due to withdrawal from
training was greater than, and not
offset by, the anticipated growth-
related increases in strength over
the same time period. In 1989,
Blimkie et al
12
proposed a model of
the effects of growth, resistance
training, maintenance training,
and detraining on strength devel-
opment in children. In a study
using that model,
13
the strength
gains seen in the training group
regressed over time in both the
maintenance and detraining groups
to levels close to, but still above,
those of the untrained control sub-
jects (Fig. 1).
In a study by Faigenbaum et al
8

evaluating the effects of strength
training and detraining on children,
the results were consistent with those
of Blimkie.
13
Despite a 53% increase
in training-induced leg-extension
strength over 8 weeks, a subsequent
8 weeks of detraining led to rapid
and significant (P<0.05) decreases in
both leg extension (−28%) (Fig. 2) and
chest press performance (−19.3%). In
the same period, the performance of
the untrained control subjects in-
creased slightly. The magnitude of
loss for the trained group was ap-
proximately 3% per week. A com-
parison of groups at completion of
detraining found no statistically sig-
nificant difference in leg extension.
Although the available data are
limited, it appears that strength
gains secondary to resistance train-
ing during prepubescence are tran-
sient and regress toward untrained
control levels. The degree of regres-
sion appears to depend on the mag-
nitude of strength gains, level of
inactivity, and duration of detrain-
ing. Unfortunately, the amount of

training required to maintain or at
Pretraining
75
T
MT
DT
C
65
55
45
Posttraining Detraining
Leg strength, N
•
m
Figure 1 Graphic illustration of Blimkie’s model demonstrating the effects of resistance
training (T), maintenance training (MT), and detraining (DT) on strength development
during normal growth (C) during childhood. The values for both the maintenance and
detraining groups regressed with time to levels close to, but above, those of the untrained
control subjects. (Adapted with permission from Blimkie CJR: Resistance training during
pre- and early puberty: Efficacy, trainability, mechanisms, and persistence. Can J Sport Sci
17;4:264-279.)
Jeffrey A. Guy, MD, and Lyle J. Micheli, MD
Vol 9, No 1, January/February 2001
33
least slow down this regression has
yet to be determined. While these
findings may bring into question
the need for maintenance programs
for children, more information is
required before specific recommen-

dations can be made.
Risks of Resistance
Training for Young
Athletes
The past 20 years have seen a
marked increase in the participation
of children in competitive sports,
and the popularity continues to
grow. Approximately 30 million
children (50% of boys and 25% of
girls) are involved in either competi-
tive organized sports or community-
based sports programs.
3
To ad-
dress the question of whether
strength training by the prepubes-
cent child is associated with an un-
acceptable risk of injury, we must
first revisit the relevant definitions.
The terms “strength training” and
“resistance training” are used to
refer to progressive resistance to
enhance performance or ability by
using submaximal amounts of
weight. The terms “weight lifting”
and “power lifting” usually refer to
the use of maximal amounts of
weight at high intensities during
competition.

It has been estimated that more
than 17,000 weight-lifting or power-
lifting injuries in adolescents re-
quiring emergency room visits oc-
cur annually.
25
However, most of
these injuries happen at home or
school and are not the result of su-
pervised activity. In several stud-
ies of adolescents, the incidence of
injury ranged between 7% and
40%.
26,27
Almost 75% of the inju-
ries were strains, with the most
common site being the lower spine.
There are also numerous case re-
ports or small series of serious
weight-lifting and power-lifting
injuries, such as cardiac rupture
due to impact by a dropped bar-
bell,
28
spondylolysis and spondy-
lolisthesis,
29
and growth-plate
injuries in the wrist.
30

Most of
these injuries were attributed to
improper lifting techniques, exces-
sive loading, or inadequate teaching
or supervision. Not surprisingly,
recommendations about the partici-
pation of young athletes in these
activities vary from supervised par-
ticipation only
25
to proscription of
weight lifting, power lifting, and
body building, as well as the use of
maximal amounts of weight in
training programs, for both chil-
dren and adolescents.
31
Strength training for young ath-
letes has received widespread sup-
port.
3,4,10,11,18,24,32,33
Rians et al,
33
looking at subclinical musculo-
skeletal injury (as evaluated on
bone scan) or muscle damage (as
estimated on the basis of serum
creatine phosphokinase determina-
tion), found no evidence of injury
in prepubescent boys after 14 weeks

of resistance training. Similar find-
ings by Blimkie et al
21
found only
mildly elevated creatine phospho-
kinase values and concluded that
short-term (duration of 20 weeks)
resistance training by prepubertal
boys did not pose any particular
risk in terms of subclinical or clini-
cal musculoskeletal injury.
Perhaps a better assessment of
the risk of injury associated with
resistance training would come
from prospective studies of closely
monitored and supervised training
programs with appropriately pre-
*
*
35
30
25
20
15
10
Pretraining
Posttraining
Mid-detraining Post-detraining
Leg-Extension Strength
(6 repetition maximum), kg

Figure 2 The effects of strength training and detraining on children demonstrated in the
study by Faigenbaum et al
8
were consistent with Blimkie’s model.
13
The trained group
(solid circles) had a 53% increase in training-induced leg-extension strength over 8 weeks,
but a subsequent 8 weeks of detraining led to a rapid and significant decrease (−28%) in
leg-extension performance, while the performance of the untrained control subjects (open
circles) increased slightly (asterisk indicates statistically significant [P<0.05] difference
between control value and previous value for trained group). A comparison of groups at
the completion of the 16-week detraining period revealed no significant difference from
the control value for leg extension. (Adapted with permission from Faigenbaum AD,
Westcott WL, Micheli LJ, et al: The effects of strength training and detraining on children.
J Strength Cond Res 1996;10:109-114.)
Strength Training for Children and Adolescents
Journal of the American Academy of Orthopaedic Surgeons
34
scribed training loads. There have
been no reported cases of serious
injuries in these studies.
9,10,18
There-
fore, it appears that the risks and
concerns associated with youth
strength training are no greater than
those associated with other sports
and recreational activities common
to this age group.
4

However, this is
based on the understanding that a
given strength training program is
competently supervised and the
young athlete is properly instructed
and underscores the need for pre-
participant history, blood pressure
measurements, flexibility screening,
and a preparticipation physical
examination. As with adult ath-
letes, while no studies have demon-
strated enhanced performance with
strength training, experience strong-
ly supports its use.
Anabolic Steroid Use
For years, athletes have taken exog-
enous substances to manipulate
their athletic performance. It is not
surprising that modern athletes
often turn to ergonomic aids like
anabolic androgenic steroids to
enhance muscle growth, increase
strength, and improve physical
performance. It has been esti-
mated that over 1 million persons
in the United States are currently
using anabolic steroids, with a
total expenditure of more than
$100 million a year.
34

Although
there is a potential for enhancing
performance, anabolic androgenic
steroids can have severe physio-
logic and emotional side effects,
such as a heightened risk for coro-
nary disease, cholestatic jaundice,
abnormal liver function, hepatic
tumors, stunted growth, gyneco-
mastia, and many psychotic disor-
ders. In addition, there is the risk
of transmission of diseases such as
acquired immunodeficiency syn-
drome and viral hepatitis through
needle sharing.
Early use of anabolic steroids in
the United States was primarily by
individuals involved in weight
training. However, gains in size
and strength prompted their use by
other athletes. Today, anabolic
steroids are consumed by both
male and female power athletes,
endurance athletes, and nonath-
letes. Given the increasing pres-
sure for athletes to perform better
and earlier, it is no surprise that the
use of anabolic steroids has breached
the boundary of age.
The use of steroids in the adoles-

cent population brings with it an
additional level of concern com-
pared to its use by older athletes.
Estimates of steroid use in the ado-
lescent population have placed the
prevalence at approximately 5% to
7% for boys and 1% to 3% for
girls.
35-37
In a recent study of pre-
adolescent middle-school students
ranging in age from 9 to 13 years,
approximately 2.7% of the students
admitted using steroids.
38
The
majority of the students felt that
steroids would make their muscles
bigger and stronger. While usage is
not exclusive to any segment of the
population, the literature suggests
that the highest level is among ado-
lescents from more affluent neigh-
borhoods, presumably because of
easier access to this relatively ex-
pensive drug.
39
Most of the steroids
used by young athletes appear to
have been obtained illegally, in-

creasing the risk of purchasing mis-
labeled or impure agents.
The physical side effects in ado-
lescent boys can range from acne
and gynecomastia to more serious
conditions, such as priapism, sodium
retention edema, and liver dysfunc-
tion after prolonged use. In girls,
clitoromegaly, hirsutism, and amen-
orrhea are common, as well as per-
manent deepening of the voice after
prolonged use. Use by children of
both sexes may also result in dimin-
ished adult height, as premature
closure of the physis is possible.
Perhaps the most serious side
effects of steroid use occur in the
behavioral sphere; in the transition
to adulthood, adolescents may be
particularly vulnerable to the conse-
quences of heightened aggression.
40
As the relatively high consump-
tion of steroids by young athletes
continues, the need for early educa-
tional intervention concerning their
effects is becoming more apparent.
One such intervention is the ATLAS
(Adolescents Training and Learn-
ing to Avoid Steroids) program.

34
The goal of that program is to edu-
cate adolescent athletes, enhance
healthy behaviors, and minimize
the factors that encourage steroid
use. Although such programs ap-
pear to be quite successful, they are
limited in both number and avail-
ability. Therefore, one cannot over-
emphasize the role of health pro-
fessionals, educators, and parents
in providing a healthy and informed
atmosphere for young athletes.
Initiation of Training
The proper initiation of strength
training for children and adoles-
cents is critical. Those supervising
young athletes—coaches, trainers,
and parents—should address several
issues before initiating a program of
training. First is whether the ath-
lete is prepared psychologically and
physically to participate in the pro-
gram. This includes making sure
that the athlete has had a prepartici-
pation physical at school or at a
physician’s office. In addition,
supervising adults should strive to
minimize pressure and stress placed
on the athlete to perform.

The second issue is whether the
athlete understands what strength
training is and what the goals of the
program are. This point cannot be
overemphasized, as misinformed
athletes are at increased risk for
injury. The athlete should under-
stand the fundamental differences
Jeffrey A. Guy, MD, and Lyle J. Micheli, MD
Vol 9, No 1, January/February 2001
35
between strength training and
weight lifting and the goals of each.
Athletes should understand that
while increasing one’s performance
is a reasonable and attainable goal,
increasing muscle size prior to the
onset of puberty is not. Safety while
training should also be emphasized.
The third issue is which strength
training program the athlete should
follow. While the specifics of indi-
vidual training programs are be-
yond the scope of this article, the
program chosen should be tailored
to the athlete in question on the
basis of age, size, experience, and
sport.
41
Access to certain facilities

and specific types of supervision
are important considerations, as not
everyone has a gym membership or
the finances to hire a personal trainer.
Parents interested in being involved
in the training process can also con-
sult the wealth of information in the
literature on strength training for
adolescents.
41-43
The objective is to
have a well-informed, carefully
supervised athlete participating in a
balanced strength-training program
with the goal of increasing strength
and improving mental attitude and
performance in sport.
Summary
The past decade has seen growing
support from both the medical and
the scientific communities regarding
the participation of young athletes in
strength training programs. Current
evidence indicates that both prepu-
bescent and pubescent children can,
in fact, increase muscle strength, but
not necessarily athletic performance,
as a consequence of resistance train-
ing. This increase in strength is
largely related to the intensity and

volume of loading and appears to be
the result of increased neuromuscu-
lar activation and coordination.
These increases in strength do not ap-
pear to be a consequence of muscle
hypertrophy, as they are in adults.
The training-induced strength gains
are largely reversible when the train-
ing is discontinued.
There is no current evidence to
support the misconceptions that chil-
dren need androgens for strength
gain, lose flexibility with training, or
are at increased risk of injury. Given
the proper supervision and appropri-
ate instruction and program design,
children involved in resistance train-
ing do not appear to be at greater
risk of injury than other young ath-
letes who have not undergone such
training. However, parents, coaches,
and trainers should be aware that
participation in unsupervised train-
ing or in activities involving rapid
and maximal loading places prepu-
bescent children at increased risk of
injury and is not recommended.
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