Strength Training for Children and Adolescents: Benefits and Risks

Abstract

Physical activity has proved to be an effective means of preventing several diseases and improving general health. In most cases, though, light to moderate efforts are suggested, for both youngsters and adults. Common sense advices call for late inception of intense, strength training-related activities, like weight lifting and plyometrics, which are usually postponed at the end of the growth age, even among sport practitioners. However, such advices seem to have a mainly an-ecdotal nature. The purpose of this review is to evaluate risks and benefits of early inception of strength training, at adolescence or even earlier, and to verify whether concerns can be grounded scientifically. Current literature does not seem to have any particular aversion against the practice of strength training by children and adolescents, provided that some safety rules are followed, like medical clearance, proper instruction from a qualified professional and progressive overload. At the same time, several studies provide consistent findings supporting the benefits of repeated, intense physical efforts in young subjects. Improved motor skills and body composition, in terms of increased fat free mass, reduced fat mass and enhanced bone health, have been extensively documented, especially if sport practice began early, when the subjects were pubescent. It can be therefore concluded that strength training is a relatively safe and healthy practice for children and adolescents.

Full text

Coll. Antropol. 37 (2013) Suppl. 2: 219–225
Review
Strength Training for Children and Adolescents:
Benefits and Risks
Davide Barbieri and Luciana Zaccagni
University of Ferrara, Department of Biomedical and Specialty Surgical Sciences, Ferrara, Italy
ABSTRACT
Physical activity has proved to be an effective means of preventing several diseases and improving general health. In
most cases, though, light to moderate efforts are suggested, for both youngsters and adults. Common sense advices call
for late inception of intense, strength training-related activities, like weight lifting and plyometrics, which are usually
postponed at the end of the growth age, even among sport practitioners. However, such advices seem to have a mainly an-
ecdotal nature. The purpose of this review is to evaluate risks and benefits of early inception of strength training, at ado-
lescence or even earlier, and to verify whether concerns can be grounded scientifically. Current literature does not seem to
have any particular aversion against the practice of strength training by children and adolescents, provided that some
safety rules are followed, like medical clearance, proper instruction from a qualified professional and progressive over-
load. At the same time, several studies provide consistent findings supporting the benefits of repeated, intense physical ef-
forts in young subjects. Improved motor skills and body composition, in terms of increased fat free mass, reduced fat
mass and enhanced bone health, have been extensively documented, especially if sport practice began early, when the sub-
jects were pubescent. It can be therefore concluded that strength training is a relatively safe and healthy practice for chil-
dren and adolescents.
Key words: strength training, weight lifting, adolescents, growth, body composition
Introduction
Modern Western societies imply increasingly seden-
tary life styles and reduced physical exercise. Technologi-
cal progress, limited outdoor activities and economic im-
provement have modified dietary habits and reduced the
amount of exercise performed by children and adoles-
cents1. It is well known that regular moderate intensity
physical activity – such as walking, cycling, or participat-
ing in sports – has significant benefits for health. Accord-
ing to the 2008 guidelines of the European Commission2,
school-aged youth should participate in moderate to vig-
orous daily physical activity for 60 minutes or more. Obe-
sity, sedentary lifestyle and poor cardio-respiratory fit-
ness in childhood and adolescence may increase the risk
of health problems later in life. The teenage years bring
many physical, social and psychological changes for the
individual. From infancy to adulthood, growth, matura-
tion and development occur simultaneously and interact:
growth consists in the increase of the size of the body as a
whole and of its parts, maturation refers to progress to-
wards the biologically mature state and development re-
fers to the acquisition of behavioral competence3.
Changes in body dimensions and composition during
growth and maturation are factors affecting strength
and motor performance4. Some changes in anthropome-
tric traits and strength in a sample of Italian adolescents
studied by Gualdi-Russo and Toselli5arereportedinFig
-
ures 1–4.
The strength and motor performance varies during
childhood and adolescence in relation to biological and
environmental factors. Among biological factors the spe-
cific contribution of maturity status is apparent: the
strength advantage of early-maturing subjects is related
to their larger body size in comparison to late-maturing
ones. These differences are more marked in boys than in
girls. Regular physical activity is an important factor
during growth and maturation, regulating body weight
and, particularly, fatness.
219
Received for publication October 15, 2011
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Information on the characteristics of elite young ath-
letes in a variety of sports is rather limited. The evalua-
tion of the maturity status is essential when working
with young athletes because individual differences in the
timing and tempo of biological maturation, particularly
during adolescence, influence body size and composition,
muscular strength and behavior. Inter-individual vari-
ability has important implications for performance, age-
-group competitions and talent identification, selection
and development. Albeit BMI is widely used in surveys of
health and nutritional status, its interpretation in young
adults, especially athletes, as an indicator of fatness
should be taken with caution. Therefore, in kinanthro-
pometry, in order to evaluate the positive effects of physi-
cal activity on body composition, the athlete’s body fat
percentage, fat mass and fat free mass are assessed.
Changes in body composition from early to late adoles-
cence can be summarized as follows: males gain almost
twice as much fat free mass as females, and females gain
about twice as much fat mass as males.
Large fat free mass is important in performances that
require force to be exerted against an object, as in shot
put or weight lifting, but can be a limiting factor in tasks
in which the body must be projected as in vertical jump
or moved across space, as in running. Fat free mass is sig-
nificantly related to strength in male adolescents3.
In sport practice, strength training was usually intro-
duced at the end of the somatic growth, that is when the
athlete was 18 years old or so. In particular, to avoid
weight lifting before and during adolescence was a com-
mon suggestion in many different contexts connected to
physical activity, from commercial gyms to physical edu-
cation courses. This conservative approach has a mainly
anecdotal origin, since usually no scientific evidence is
given in order to support it. Most of the concerns are re-
lated to the possibility of injuries or diminished growth
potential. Still, many of the young athletes who regularly
compete in various sport disciplines begin their training
very early, when they are pubescent or even pre-pubes-
cent. Beside the fact that students begin physical educa-
tion at primary school in many countries, early inception
of sport practice is often suggested in order to take ad-
vantage of the ease and quickness with which children
and adolescents improve their motor control and acquire
new sport skills.
Furthermore, adolescents can be observed while lift-
ing weights during their usual daily activities, outside a
sport or training facility: carrying a schoolbag, a suitcase,
a shopping bag or other items, lifting them from the
floor. Without proper training, they may do it rounding
their back or using any other improper technique, while
the correct one could be learnt under supervision from a
weight lifting instructor, inside a gym.
D. Barbieri and L. Zaccagni: Resistance Training before and during Adolescence, Coll. Antropol. 37 (2013) Suppl. 2: 219–225
220
0
20
40
60
80
100
120
140
160
180
WEIGHT (kg) HEIGHT (cm) BMI (kg/m )
2
12 yrs
13 yrs
14 yrs
Fig. 1. Anthropometric traits in a sample of Italian adolescent
males5by age.
0
20
40
60
80
100
120
140
160
WEIGHT (kg) HEIGHT (cm)
12 yrs
13 yrs
14 yrs
BMI (kg/m )
2
Fig. 2. Anthropometric traits in a sample of Italian adolescent
females5by age.
0
10
20
30
40
50
60
70
80
90
100
kg
RIGHT HAND
GRIP
LEFT HAND
GRIP
LEG
STRENGTH
12 yrs
13 yrs
14 yrs
Fig. 3. Strength values in a sample of Italian adolescent males5
by age.
0
10
20
30
40
50
60
70
80
90
kg
RIGHT HAND
GRIP
LEFT HAND
GRIP
LEG
STRENGTH
12 yrs
13 yrs
14 yrs
Fig. 4. Strength values in a sample of Italian adolescent females5
by age.
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It is therefore necessary to evaluate whether the ad-
vice to postpone strength training in general and weight
lifting in particular at the end of adolescence is sound
and can be substantiated scientifically. The main pur-
poses of the present review are the following: to find any
evidence in current literature of benefits or dangers for
the health of the adolescents related to early inception of
strength training, and to compare the relative stress of
this kind of physical activity to other common sport prac-
tices.
Strength Training: Concepts and Objectives
Strength training is a form of physical activity, usu-
ally structured and planned, involving intense efforts
against a resistance. Its main aim is to increase muscular
strength, in order to improve performance, at least in
case a sport is practiced. It is extensively adopted in
power-oriented sports, like sprinting6and soccer7, even if
its benefits are recognized also in endurance sports, like
long distance running8,9 and cross country skiing10,11.In
a non-competitive environment instead, strength train-
ing is adopted for many different purposes. For example,
strength training may be used to improve overall fitness,
increasing muscle hypertrophy and reducing body fat-
ness at the same time. In fact, strength training can be
an effective means to improve body composition12.In
other cases, some individuals may adopt it in order to ac-
complish some professional goal, like achieving the de-
gree of physical fitness which is required in the military
or to join the fire brigade.
To train strength, muscular force is applied against
some kind of resistance. In most cases, especially when
the individual is healthy, resistance is provided by free
weights, like barbells, dumbbells or the athlete’s own
body weight, or by weight machines, like the leg press,
the lat machine etc. This kind of training is usually
adopted in sport conditioning, because the load can be in-
creased progressively according to the athlete’s strength,
which can be considerable. Athletes employ gravity also
in other ways in order to improve their performances,
like in plyometrics or high-impact training, where body
mass is accelerated dropping from a pre-determined
height, according to the athlete’s ability and conditioning
level. This kind of strength training is usually considered
the most dangerous, because the real impact forces ap-
plied to the athlete’s body (bones, muscles, tendons, liga-
ments etc.) are not easily measured, as in weight lifting.
Since force is defined as mass times acceleration, we can
say that weights mainly focus on the first factor, while
plyometrics relies on the second to increase force. None-
theless, also weights can be accelerated, in order to in-
crease force production without adding kilograms, and
advanced plyometrics may imply added weight by means
of weighted belts or vests.
It must be considered, though, that similar strength
training effects can be found in sport practices other
than weight lifting or plyometrics, like sprinting, gym-
nastics and other kinds of power-oriented sports, or team
sports involving leaping and bouncing, like volleyball and
basketball. These types of physical efforts produce great
acceleration, which, applied to the athlete’s body mass,
produce great force. Nonetheless, these intense efforts
are usually practiced by children, even outside a sport
environment, simply while playing with their peers.
Strength training has in important role in rehabilita-
tion after injuries, especially those which involve surgery
and/or a long period of immobilization, in order to re-gain
the physiological muscle hypertrophy and joint range of
motion13–18. In case of injuries to lower limbs, when the
patient is still lying in bed, body weight can be excessive
and not suitable for post-surgery rehabilitation. There-
fore, non-bodyweight bearing exercises can be used, by
means of cables and/or small weights, attached to the an-
kles of the patient, like in leg raises and knee extensions.
Body weight can be excessive also for healthy individ-
uals who have a low relative strength, that is a low
strength-to-body weight ratio. A push up, a pull up or
even a body weight squat can be a demanding task for
people who are too young, elderly, overweight or out of
shape. Free weights or machines can provide a controlled
and adjustable source of resistance. For example, a push
up can be effectively substituted by a bench press, a pull
up by a lat pull down using a lat machine, a body weight
squat by a leg press, involving more or less the same
muscle groups. Weights can be adapted to the individu-
als’ actual strength, which may be relatively low com-
pared to their own body weight.
Other kinds of resistance than weights may be ap-
plied in order to increase muscular strength, like elastic
bands, or friction, as in water or on a steady bike. In fact,
gravity is not necessarily present (e.g. astronauts during
space missions are at risk of losing considerable amounts
of muscle mass19,20) or not fully applicable. Orthopedics
patients may have access to a swimming pool, where the
weight-bearing effort of an injured knee, ankle or hip can
be reduced. At the same time, also competitive swimmers
may use swim paddles to increase the resistance provided
by water.
Exercises are usually performed in sets of several rep-
etitions (i.e. consecutive lifts). If heavy loads are em-
ployed, providing stimulus for maximal strength, then
repetitions are necessarily low in numbers. When the
load is moderate, in order to improve body composition
and cardiovascular fitness, then the overall number of
repetitions can be considerably high. The main training
parameters are intensity and volume. Intensity is given
as percentage of the maximal load which can be lifted for
the prescribed number of repetitions: 1 repetition-maxi-
mum (RM) is the load which can be lifted just once, 10
RM is the load which can be lifted 10 times within one
set. Strength training implies relatively heavy loads, be-
tween 60% and 100% of 1 RM, the so-called »strength
training zone«21. For example, the 90% of 1 RM is a quasi
maximal load, allowing for small volume (i.e. low repeti-
tions). Volume is the total number of repetitions per ex-
ercise. For example, performing 3 sets of 10 repetitions in
one given exercise determines a volume of 30 repetitions.
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The most common strength training exercises are
listed in Table 1, with the discipline in which they are
usually practiced, even if in most cases athletes involved
in different sports may use a blend of them. This is espe-
cially true in body building, where the overall balanced
development of muscle mass is of great importance.
Therefore, body builders use most of the listed exercises
(and even more than those), while strength training for
athletes usually comprises a small set of exercises, like
the clean, the squat and the bench press, involving most
skeletal muscles in a coordinated fashion.
Benefits and Risks of Strength Training
for Children and Adolescents
For reasons which have been mainly reported anec-
dotally, strength training, especially if involving weight
lifting, has been considered dangerous for children and
adolescents, and at risk of limiting their growth. How-
ever, the American College of Sports Medicine highlights
that there is no current scientific evidence of the fact
that strength training and weight lifting are inherently
dangerous or can restrain the growth of children and ad-
olescents. Like any other kind of sport practice, there are
some risks which can be considerably diminished follow-
ing a small set of suggestions: proper supervision form
an expert adult, warm up and stretching before lifting,
focus on proper form rather than load, gradual resistance
increases as technique, strength and control improve22.
The American Academy of Pediatrics gives compara-
ble guidelines, implying that strength training can be
safe and effective for children and adolescents, provided
that medical clearance is granted. At the same time, it
discourages them from practicing sports, like Olympic
weightlifting and powerlifting, which involve maximal
lifts23–25.
A similar position has been taken by the National
Strength and Conditioning Association, which is in favor
of supervised and appropriately prescribed strength
training for both pre-adolescents and adolescents26.
In strength training, the gains in muscular strength
are often associated with improvements in body composi-
tion. In a study by Faigenbuam et al.27 a group of boys
and girls aged between 8 and 12 followed a twice-a-week
resistance training program for 8 weeks. After warm up
and stretching, the training group performed the follow-
ing 5 exercises: leg extension, leg curl, bench press, over-
head press and biceps curl. Both training and control
groups continued physical education at school. As ex-
pected, strength gains in the training group were signifi-
cant compared to both pre-training and control. Also im-
provements in body composition were significant:
skinfold thickness decreased of 2.3% on average, com-
pared to an increase of 1.7% in control group. It is inter-
esting to note that upper arm, chest and hip girths did
not change significantly. The only exception was the
thigh girth, which anyway increased relatively less than
control (+2.4% vs. +3.9%).
The volume-intensity schema adopted was the popu-
lar Delorme method: 3 sets of 10 repetitions each, the
first one with 50% of 10 RM, the second one with 75% of
10 RM and the third one with 100% of 10 RM. Delorme
was among the first physicians who realized the impor-
tance of strength training – and weight lifting in particu-
lar – in rehabilitation after injuries28.
A similar pyramiding method was adopted in a study
by Schwingshandl et al.29. Obese children and adoles-
cents were prescribed a diet with caloric restriction. Un-
fortunately, diet alone may reduce both fat and fat free
mass. Subjects were therefore divided into 2 groups:
training and control. After some light aerobics and stre-
tching as a warm up, the training group performed 3 to 4
sets, 10 repetitions each, of the prescribed exercises,
which were chosen to involve all major muscle groups.
The first set was performed using the 50% of 10 RM.
Load was increased progressively in each set, until mus-
cle failure because of fatigue. When the child was able to
complete more than the prescribed 10 repetitions in the
last set, the load was increased in the following training
session. After 12 weeks, weight change was not signifi-
cant in both groups, while the increase in fat free mass
was significantly higher in the training group than in
control, implying that resistance training may have a
positive effect on body composition in fat reduction pro-
grams for obese children and adolescents.
Supervised strength training, involving weight lifting
(bench press, leg extension, lat pull down etc.) and stre-
tching, after an adequate warm up, has proved to be ef-
fective in a group of children, males and females, increas-
ing strength, reducing skinfold thickness, improving
body composition, motor skills and flexibility30.
In a study by Watts et al.31 obese adolescents were in-
volved for 8 weeks in a strength training program con-
sisting in 1 hour of circuit training, 3 times per week, in-
cluding both cycle ergometer and resistance training.
Since the program was primarily designed to treat obe-
sity rather than improving strength, exercise intensity
was kept between 55–70% of pre-training 1 RM. Training
reduced abdominal and trunk fat, thus diminishing car-
diovascular and metabolic risks, and increased strength,
body composition and overall fitness at the same time.
Even if the main purpose of strength training is to in-
crease muscle strength, it seems to have a positive carry
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222
TABLE 1
COMMON STRENGTH TRAINING EXERCISES
Olympic
weightlifting Powerlifting Body
building Body weight
training
Snatch
Clean and
jerk
Squat
Bench press
Deadlift
Overhead
presses
Biceps curls
Leg extensions
Leg curls
Rowers
Push ups
Pull ups
Parallel dips
Body weight
squats
One-leg squats
Sit ups
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over also in bone density and therefore it qualifies as an
interesting means for preventing and reducing osteopo-
rosis. This is particularly true for children: if strength
training is adopted early, bone mass gains last longer.
Skeletal exposure to mechanical loading during growth
seems to be an effective strategy to increase bone mass
and density, according to Khan et al.32. In a study by
Fuchs et al.33, high impact training is used to verify its ef-
ficacy in improving skeletal mass in a group of elemen-
tary school children. Bone mineral content, bone area
and bone mineral density were adopted as indices of bone
health. The training protocol consisted in 100 drop
jumps form a 61 cm box, 3 times per week for 7 months,
implying ground reaction forces up to 8 times body
weight. However, the adopted method proved to be safe
and effective in improving the above mentioned parame-
ters at the femoral neck and lumbar spine. Actually, in a
popular sport like gymnastics, impact forces in drop
landings range from 8.2 to 11.6 times body weight, ac-
cording to a study by Ozguven and Berme34.
Even if the authors say that the program could be in-
troduced in physical education classes, its main limita-
tion may be in the fact that high-impact training may re-
sult in an excessive effort for overweight children. Still,
in the training group no injuries occurred during the
whole duration of the study. Actually, selected children
had to be within the 20% of the recommended weight for
height and age. The benefits at the femoral neck per-
sisted even after several months of detraining, when the
same bone health parameters were re-assessed in both
exercise and control group35.
Significant positive effects of impact training on bone
mineral content at the hip was also found by Gunter et
al.36 in a longitudinal study. The benefits of 7 months of
impact training on a group of school children were par-
tially maintained up to 8 years later.
Osteoporosis is a major problem especially for adult
women. Even if considerable improvements in terms of
bone health can be assessed in adults engaging in some
form of strength training, the benefits do not seem to
persist as long as in children or adolescents, suggesting
that early inception of intense physical exercise may be
prescribed for long-lasting improvements. A study by
Winters and Snow37 assessed bone mineral density in a
group of females aged 30–45, before and after a 12 month
training period. The training program included both
high impact and resistance training (squats, lunges and
calf raises). Drop jumps off a box generated ground reac-
tion forces of 4 to 5 times body weight. Intensity was
gradually increased using weighted vests. After the trai-
ning period, exercisers improved their bone mineral den-
sity and strength significantly, with respect to both base-
line (pre-training) and control values. Unfortunately
though, after 6 months of detraining, values decreased
significantly towards baseline values.
A study by Kannus et al.38 evaluated the effects of
playing starting age on bone mineral content of the dom-
inant arm in a group of female tennis players. Athletes
had a significantly higher difference in bone mineral con-
tent between dominant and non-dominant arm com-
pared to control. The difference was 2 to 4 times greater
in individuals who had started playing tennis before or at
menarche, compared to those who had started 15 years
after menarche. Tennis resembles strength training and
may carry over similar effects on the bones since it con-
sists of ballistic and explosive movements, handling a
light implement. Even if the involved masses are small
(ball and racquet), the acceleration produced during the
impact may be very large, producing great force against
the dominant arm.
Similar positive effects on bone mineral density of fe-
male gymnasts were found by Proctor et al.39 in the
whole body and in particular in the upper limbs, without
any significant bilateral differences, which is a major ad-
vantage compared to tennis. Gymnastics exercises, like
pull ups and ring or parallel dips, are often employed in
body weight strength training, for their carry over to up-
per body muscle strength.
Swimming and cycling are among the most popular
sports and bring several health benefits. However, bones
seem to be less directly addressed by these activities, be-
cause of their non-weight-bearing nature, which limits
the loading on the skeleton. A group of well trained ado-
lescent females (track and field athletes, gymnasts and
water polo players) were assessed by Greene et al.40.Al-
though all the selected sports require intense physical
work, gymnastics involves weight-bearing in both the up-
per and lower body, track-and-field (sprints and jumps)
only in the lower body, and water polo has no weight-
-bearing component. Water polo players did not show
greater bone strength or muscle size in the lower leg
compared to controls. On the contrary, gymnasts showed
significantly greater bone strength than non active fe-
males. Also track-and-field athletes displayed greater
bone strength in the lower leg, compared to controls. The
gymnasts showed the greatest musculoskeletal benefits
in the upper body. Despite intense training, water polo
players showed no significant benefits in musculoske-
letal health in the lower body and only limited benefits in
the upper body when compared with non active girls.
Ferry et al.41 investigated bone mineral density in fe-
male adolescent soccer players, swimmers and control
group. Bone mineral density was significantly higher in
soccer players compared with swimmers. In contrast,
swimmers had weaker bones than controls, despite the
fact that female swimmers cannot be considered seden-
tary subjects.
Effects of strength training on connective tissues (lig-
aments and tendons in particular) have not been as
widely assessed as those on bones. However, a recent
study42 has found a positive correlation between resis-
tance training (in particular Olympic weightlifting) and
cruciate ligaments’ cross sectional areas. The authors
conclusions are that the benefits were induced by early
inception of heavy training at the age of puberty.
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Discussion and Conclusions
An meaningful distinction should be made between
weight lifting for strength training and Olympic weight-
lifting. The latter implies competitions in which maximal
or even supra-maximal (when the lift fails) loads are em-
ployed, as in powerlifting. In strength training instead,
sub-maximal weights, which can be lifted more than
once, are used. This distinction may account for a differ-
ent risk factor between the aforementioned disciplines.
In general, whenever a maximal effort is required, as in
competitive sport, it is believed that risks tend to be pres-
ent in a higher percentage than in recreational activities.
More specifically, even if strength training may be stren-
uous and intense, if no maximal loads are employed, than
it can be considered a safe and effective form of physical
activity for most individuals, including children and ado-
lescents, provided that proper instruction and supervi-
sion are given.
However, a study by Hamill43 questions the common
belief that resistance training is safer than Olympic
weightlifting, since both appear to be relatively safe ac-
cording to his findings, especially if compared to other
sports. The surveyed subjects were UK students, aged 13
to 16. Practicing both Olympic weightlifting and weight
training had an injury rate of only 0.0012 per 100 partici-
pation hours. Individually, both disciplines scored well
below other popular British sports, like soccer, rugby or
even athletics.
In a study by Risser et al.44 muscle strain, a non-dis-
abling injury, was reported to be the most common acci-
dent among high school American football players prac-
ticing weight lifting as a form of strength training. The
cumulative percentage of injuries among all athletes was
a reasonable 7.6%, corresponding to 0.082 injuries per
person/year. Much higher rates can be found in adoles-
cent45 or amateur46 soccer players. However, the study
did not specify whether injuries were caused by maximal
lifts (i.e. excessive load) or poor form, as it may happen in
a competitive environment, where fatigue and strive for
performance may lead to an excessive demand on the
athlete's physical capabilities.
The topic of growth and strength training could be
further assessed from an endocrine point of view, consid-
ering the relationship between exercise and hormonal re-
sponses. A review by Kraemer and Ratamess47 highlights
the well established finding that resistance training and
growth hormone are positively correlated, but further re-
search is needed in order to verify whether strength
training could induce positive endocrine responses in ad-
olescents.
In conclusion, early inception of strength training, at
adolescence or even earlier, does not seem to imply hig-
her risks than other popular sport disciplines, provided
that the young athletes follow the aforementioned guide-
lines. In particular, supervision by an expert instructor,
focus on proper technique and cautious progression in in-
creasing loads are the most common advices which must
be adhered to. On the positive side, resistance training
has proved to increase basic motor skills, like muscle
strength, coordination and flexibility, but also body com-
position, in terms of improved fat free to fat mass ratio
and increased bone health.
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D. Barbieri
Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Corso Ercole I d’Este 32, Ferrara, Italy
e-mail: davide.barbieri@unife.it
TRENING SNAGE ZA DJECU I ADOLESCENTE: KORISTI I RIZICI
SA@ETAK
Pokazalo se da je tjelesna aktivnost efektivno sredstvo u prevenciji bolesti i pobolj{anju op}eg zdravlja. No, u ve}ini
slu~ajeva se ipak preporu~a laka ili umjerena tjelovje`ba, kako za djecu tako i za odrasle. Nekad se znaju preporu~ati i
intenzivni treninzi snage, poput dizanja utega ili pliometrije, koji se ~ak i kod sporta{a prakticiraju tek pri kraju raz-
vojne dobi. Takve preporuke mogu biti dvojake prirode i cilj je ovog rada procijeniti rizike i koristi ranog uvo|enja
treninga snage, u adolescenciji ili ~ak ranije, kako bismo potvrdili postoji li znanstveno opravdana zabrinutost. Iz aktu-
alne literature se ~ini da ne postoji averzija prema treninzima snage kod djece i adolescenata, ukoliko se primijenjuju
odre|ena sigurnosna pravila poput lije~ni~ke dozvole, to~nih i detaljnih instrukcija od strane kvalificiranog profesio-
nalca i progresivno optere}enje. U isto su vrijeme neke studije utvrdile korist od ponavljaju}eg, intenzivnog tjelesnog
napora kod mladih. Zabilje`ene su pobolj{ane motori~ke sposobnosti, manja koli~ina tjelesne masno}e i zdravije kosti,
pogotovo ako se s treniranjem zapo~ne rano, u pubertetu. Iz navedenog se mo`e zaklju~iti da su treninzi snage sigurni i
zdravi za djecu i adolescente.
D. Barbieri and L. Zaccagni: Resistance Training before and during Adolescence, Coll. Antropol. 37 (2013) Suppl. 2: 219–225
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