PLEASE SCROLL DOWN FOR ARTICLE
This article was downloaded by:
21 January 2011
Access Details: [subscription number 932617650]
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-
41 Mortimer Street, London W1T 3JH, UK
Journal of Sports Sciences
Publication details, including instructions for authors and subscription information:
The Long-Term Athlete Development model: Physiological evidence and
; Mark De Ste Croix
; Rhodri Lloyd
; Rob Meyers
; Marjan Moosavi; Jon Oliver
; Kevin Till
School of Health and Bioscience, University of East London, London, UK
Faculty of Sport, Health
and Social Care, University of Gloucestershire, Gloucester, UK
Cardiff School of Sport, University of
Wales Institute, Cardiff, UK
Carnegie Faculty of Sport and Education, Leeds Metropolitan University,
Children's Health and Exercise Research Centre, University of Exeter, Exeter, UK
First published on: 04 January 2011
To cite this Article Ford, Paul , De Ste Croix, Mark , Lloyd, Rhodri , Meyers, Rob , Moosavi, Marjan , Oliver, Jon , Till,
Kevin and Williams, Craig(2011) 'The Long-Term Athlete Development model: Physiological evidence and application',
Journal of Sports Sciences, 29: 4, 389 — 402, First published on: 04 January 2011 (iFirst)
To link to this Article: DOI: 10.1080/02640414.2010.536849
Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf
This article may be used for research, teaching and private study purposes. Any substantial or
systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or
distribution in any form to anyone is expressly forbidden.
The publisher does not give any warranty express or implied or make any representation that the contents
will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses
should be independently verified with primary sources. The publisher shall not be liable for any loss,
actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly
or indirectly in connection with or arising out of the use of this material.
The Long-Term Athlete Development model: Physiological evidence
, MARK DE STE CROIX
, RHODRI LLOYD
, ROB MEYERS
, JON OLIVER
, KEVIN TILL
, & CRAIG WILLIAMS
School of Health and Bioscience, University of East London, London, UK,
Faculty of Sport, Health and Social Care,
University of Gloucestershire, Gloucester, UK,
Cardiff School of Sport, University of Wales Institute, Cardiff, UK,
Carnegie Faculty of Sport and Education, Leeds Metropolitan University, Leeds, UK, and
Children’s Health and Exercise Research Centre, University of Exeter, Exeter, UK
(Accepted 29 October 2010)
Within the UK, the ‘‘Long Term Athlete Development’’ (LTAD) model has been proposed by a variety of national
governing bodies to offer a ﬁrst step to considering the approach to talent development. The model, which is primarily a
physiological perspective, presents an advancement of understanding of developing athletic potential alongside biological
growth. It focuses on training to optimize performance longitudinally, and considers sensitive developmental periods known
as ‘‘windows of opportunity’’. However, it appears that there are a number of problems with this theoretical model that are
not necessarily transparent to coaches. Principally, the model is only one-dimensional, there is a lack of empirical evidence
upon which the model is based, and interpretations of the model are restricted because the data on which it is based rely on
questionable assumptions and erroneous methodologies. Fundamentally, this is a generic model rather than an
individualized plan for athletes. It is crucial that the LTAD model is seen as a ‘‘work in progress’’ and the challenge,
particularly for paediatric exercise scientists, is to question, test, and revise the model. It is unlikely that this can be
accomplished using classical experimental research methodology but this should not deter practitioners from acquiring valid
and reliable evidence.
Keywords: Long-Term Athlete Development Model, growth and maturation, youth athletes
Talent development is holistic in nature due to the
complex interaction of interdisciplinary issues that
directly impact on athletic opportunity and progres-
sion. Such concepts have been critically acknowl-
edged and documented in a recent comprehensive
report (Bailey et al., 2010). Bailey and colleagues
(2010) discuss such interactions methodically and
recommend future considerations to sport and
physical activity stakeholders who wish to enhance
participation and performance levels. Such discus-
sion has also been documented in recent review
articles (Burgess & Naughton, 2010; Phillips, Da-
vids, Renshaw, & Portus, 2010). Although we
recognize such considerations are signiﬁcant, this
review focuses upon the popular ‘‘Long-Term
Athlete Development’’ (LTAD) model (Balyi &
Hamilton, 2004), which by design is fundamentally
based upon physiological principles and which will
be the sole focus here. The requirement to identify
new methods by which talent can be nurtured (which
in itself is contentious as to its deﬁnition) is
paramount for coaches and practitioners. In parti-
cular, direct techniques to advance paediatric sport-
ing development are of signiﬁcant interest. However,
within this speciﬁc population there are many
extraneous factors (including degree of maturation,
and anatomical, neurological, hormonal, and mus-
culoskeletal changes in structure) that must be
incorporated within the planning of any form of
physical training (Malina, Bouchard, & Bar-Or,
2004; Tihanyi, 1990). These factors relate to an
integrated development of genes and hormones that
are coordinated according to a biological clock and
other factors (i.e. nutrients and environmental
factors), which are time independent but which all
affect the physiological systems of the body (Malina
Correspondence: P. A. Ford, School of Health and Bioscience, University of East London, Stratford Campus, Romford Road, London E15 4LZ, UK.
Journal of Sports Sciences, February 15th 2011; 29(4): 389–402
ISSN 0264-0414 print/ISSN 1466-447X online Ó 2011 Taylor & Francis
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
et al., 2004; Tihanyi, 1990). However, prior to the
last decade, the amalgamation of all these factors had
not been accounted for, something which has
hindered our understanding of the effects of training
on paediatric athletes (Balyi & Hamilton, 2004).
Currently, the most relevant and well-known model
to include such paediatric developmental considera-
tions has been held to be the LTAD model (see
Although the LTAD model is not novel (Bompa,
1995; Riordan, 1977), it has been constructed on the
basis that it combines successfully employed training
methods alongside a greater scientiﬁc basis for
children and adolescents (Balyi & Hamilton, 2004;
Harre, 1982). Worldwide, as the LTAD model has
been advanced it has been adopted and applied by
national governing bodies, and consequently practi-
tioners, for the development of children into elite
athletes (Badminton England, 2006; British Gym-
nastics, 2006; England and Wales Cricket Board,
2005). The model attempts to balance training load
and competition throughout childhood and adoles-
cence, as previously it has been suggested that there
has been too much focus placed upon results rather
than assisting optimal development processes (Balyi
& Way, 1995; Bompa, 1995). Although Platonov
(1988) highlights the number of hours required to
maximize each development stage from initial basic
training through to adult maintenance, the LTAD
model principally distinguishes four stages of train-
ing development that account for enhancing general
athletic capabilities and sport specialization after
pubertal changes: FUNdamental phase, Training to
train phase, Training to compete phase, and Train-
ing to win phase (Balyi & Hamilton, 2004). It is
suggested that through objective physiological assess-
ment tools (e.g. peak height velocity, peak weight
velocity), coaches can account for individual matura-
tion rates for each athlete so that they can apply the
relevant training protocols depicted in each phase of
the model. Such practice advances chronological age
classiﬁcation, which seems to be inherently ﬂawed
due to variation in growth and maturational rates
between individuals and subsequent variance in
training ‘‘readiness’’ as will be discussed later in this
review (Balyi & Hamilton, 2004; Bompa, 1995). In
addition, using appropriate training stimuli linked to
natural growth and maturation processes (an addi-
tional factor from this model) utilizes the concept
that there are ‘‘windows of opportunity’’ to accel-
erate and enhance physical development.
Two contemporary UK coaching texts have
directly advocated the underlying concepts and
application of the LTAD model for practitioners in
sports performance and athletic development (Balyi
& Stafford, 2005; Balyi & Williams, 2009). The texts
highlight to practitioners that the model is a coaching
framework that has been constructed using a variety
of sources and experiences.
However, at present and to the best of the authors’
knowledge, there is a distinct lack of empirical data
to support such a long-term periodized model.
Therefore, the LTAD model must be viewed as a
work in progress and caution is urged to ensure that
the model does not become too enshrined as ‘‘fact’’.
Much of the evidence lacks any signiﬁcant long-
itudinal or experimental data, and includes animal-
based literature to rationalize its structure (Szmodis,
1991). Indeed, Balyi and Hamilton (2004) highlight
that their work is based on ‘‘empirical observations’’,
which although apparently well informed, lack
scientiﬁc validity due to inherent subjectivity issues.
In addition, it appears that there is no evidence that
failure to exploit these ‘‘windows of opportunity’’
with appropriate training will result in inhibited
development and that the athlete will experience a
‘‘ceiling’’ effect on performance. Bailey et al. (2010)
correctly question whether the ‘‘windows of op-
portunity’’ actually raise the ceiling for future
potential or just allow an athlete to reach their
ceiling performance level at a younger age. Beunen
and Malina (1996) clearly show individual variance
in the rate of athletic performance development
associated with growth and maturation, but there
seems to be a lack of clarity on the training
stimulus required to facilitate these developmental
spurts. Due to the lack of an agreed method of
quantifying training per se, and the lack of
paediatric data, plus the wide range of stimuli
needed for different sports, it appears an almost
impossible task to elucidate the stimulus–training
response question. The model has recently come
under some direct criticism from practitioners for
such reasons (e.g. Bailey et al., 2010), indicating a
scientiﬁc examination of the LTAD model speci-
ﬁcally would seem to be very appropriate. The aim
of this review is to examine physiological ﬁtness
components located within the LTAD model with
regards to trainability, to distinguish if this has
been effectively encompassed within the prescrip-
tions of the model, and to directly evaluate the
concept of ‘‘windows of opportunity’’.
Impact of growth and maturation on athletic
There have been numerous references to physical
literacy in the literature over the years and also many
philosophical and physiological debates, mainly by
physical educators, over its importance throughout
the human life span (Whitehead, 2001, 2004).
Physical literacy has been deﬁned as the extent of a
390 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Figure 1. Adaptation to training and optimal trainability (adapted from Balyi & Way, 2002; in Balyi & Hamilton, 2004).
Long-Term Athlete Development model 391
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
person’s ability to capitalize on his or her embodied
dimension (Whitehead, 2004) or as a combination of
kinaesthetic intelligence and the ability for skilful
actions (Arnold, 1979). Physiologically, physical
literacy is the development and the competence in
fundamental movement skills (e.g. walk, run, jump,
throw) and fundamental sport skills (e.g. catch, hop,
gallop) that permit a child (or adult) to move
conﬁdently in a wide range of physical activity,
rhythmic, and sport situations (Higgs et al., 2008). It
is has been shown that, compared with the typically
developing child, children with motor learning
difﬁculties demonstrate less physical literacy, are less
active and more disruptive in regular physical
education classes and during ‘‘school holidays’’
(Bouffard, Watkinson, Thompson, Dunne, &
Romanow, 1996), and have lower overall ﬁtness
(Hands & Larkin, 2006). While the negative effects
of reduced movement proﬁciency on health-related
ﬁtness have been well documented in children
(Okely, Booth, & Chey, 2004; Okely, Booth, &
Patterson, 2001a, 2001b), the literature regarding
the importance of developing physical literacy and
motor skill ﬁtness for LTAD is limited.
The development of fundamental movement skills
starts at birth and may continue until 11–12 years of
age, depending on the complexity of the skill
(Gabbard, 1992). Many scientists have proposed
that each of the fundamental movements has a series
of developmental stages, with each stage possessing a
different degree of complexity (Flinchum, 1975;
Gabbard, 1992; McClenaghan & Gallahue, 1978).
Children need to acquire mature fundamental
movement patterns to improve their performance
(Gabbard, 1992; McClenaghan & Gallahue, 1978),
and acquiring mature patterns requires greater
speed, balance, control, strength, and coordination
to be able to pass through different stages. The
scientiﬁc literature regarding the natural process of
motor development ﬁtness may partly support the
LTAD model for the development of physical
literacy. From a neurological perspective, Rabino-
wicz (1986) noted the periods of peak brain
maturation through childhood. Such development
at 6–8 years and 10–12 years of age seems to
coincide with the ‘‘windows of opportunity’’ for
physical literacy tasks (fundamental and sports
speciﬁc) in the LTAD model (Balyi & Hamilton,
2004; Higgs et al., 2008) and improvements in
motor coordination (Cratty, 1986). However, such
developments may represent accelerated periods of
development, but there is no evidence that such
periods offer greater ‘‘sensitivity’’ to training.
The literature regarding the trainability of physical
literacy provides some scientiﬁc evidence to support
the LTAD model, although it is not completely
convincing. The variety and diversity of the indica-
tors chosen to express the proﬁciency of physical
literacy makes it particularly difﬁcult to draw clear
conclusions, and further work to provide clariﬁcation
in this area is certainly required. The importance of
providing learning opportunities in the early years of
life for the development of cross-body coordination
and fundamental movement skills has been reported
previously (Dennis, 1960; McGraw, 1935, 1959).
However, in more recent years, several studies have
investigated the effect of training on physical literacy
during childhood. Ingle and colleagues (Ingle, Sleap,
& Tolfrey, 2006) showed that a mixture of plyo-
metrics and resistance training could improve
fundamental sport skills temporarily among early
pubertal boys, although the authors only measured
strength-related performance outcomes and not the
actual quality of fundamental sport skills. Graf et al.
(2005) showed that a long-term school-based inter-
vention can improve aspects of physical literacy
among 6- to 9-year-olds, but a 6 year follow-up
study demonstrated that a year-long intervention
during childhood did not have long-lasting effects on
overall physical literacy (Barnett et al., 2009). In both
instances, however, movement quality was not
assessed. These data would seem to contradict the
‘‘windows of opportunity’’ concept proposed in the
LTAD model, whereby training within certain
physical literacy skills at certain stages may result in
greater long-term development of those skills.
Gallahue and Ozmun (1998) and Gallahue and
Donnelly (2003) also suggest a ‘‘proﬁciency barrier’’,
whereby progression onto more advanced specialized
or sports-speciﬁc skills are dependent on the prior
foundation of fundamental movement patterns,
reinforcing the motor development literature. Evi-
dently there is much inconsistency in the current
literature surrounding the long-term effects of
fundamental movement/sport skills training, both in
terms of methodology and outcome, and further
multidisciplinary, longitudinal research is required.
Flinchum (1975) have shown the importance of
providing instruction for rapid development of more
complex movements such as mature throwing
patterns among 5-year-olds. Furthermore, Derri
and colleagues (Derri, Tsapakidou, Zachopoulou,
& Kioumourtzoglou, 2001) conducted a 10 week
music and movement programme with children aged
4–6 years, and reported signiﬁcant improvements in
the quality of more complex movement patterns.
Further work by Deli and colleagues (Deli, Bakle, &
Zachopoulou, 2006) suggested that ‘‘free play’’
(compared with instruction) seemed unable to
guarantee the development of more complex skills,
lending support to Gabbard (1992), who suggested
that ‘‘Proﬁcient kicking, like proﬁcient throwing,
may not be achieved through the natural course of
childhood development’’ (p. 295).
392 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
In summary, it appears that there is reasonable
anecdotal and some physiological evidence to sup-
port the idea of enhanced neural and muscular
adaptations (due to the plasticity of the neuromus-
cular system) through exposure to regular and
structured fundamental movement skills and funda-
mental sport skills training in childhood. However,
further research is needed to quantify the existence of
the ‘‘window of opportunity’’ concept for funda-
mental movement/sport skills, and if training these,
especially in the earlier years, could manifest it
through the later stages of the athletic development
The development of aerobic ﬁtness and its impact on
performance is inﬂuenced by growth-related changes
to an individual’s central and peripheral cardiovas-
cular system, muscular function, cellular capacity,
body composition, and metabolic capability (Row-
land, 1985). The intra- and inter-degree of inﬂuence
these components have upon aerobic ﬁtness varies
throughout childhood and adolescence (Naughton,
Farpour-Lambert, Carlson, Bradney, & Van Praagh,
2000). Peak oxygen uptake, acknowledged as the
‘‘gold standard’’ criterion method of assessing an
individual’s aerobic ﬁtness (Jones & Carter, 2000;
Naughton et al., 2000), increases from infancy into
adulthood, possibly in a linear fashion with body size
(Armstrong & Welsman, 1994; Bouchard, Malina, &
Pe´russe, 1997; Viru et al., 1999). Although there is a
large amount of supportive literature to suggest that
from a young age children naturally possess a well-
developed aerobic capacity (Boisseau & Delamarche,
2000), different methods of physical training have
been shown to enhance the development of aerobic
capacity in children and adolescence (Viru et al.,
1999). For example, it has been suggested that
relatively high-intensity prolonged training will pro-
duce signiﬁcant gains (Tolfrey, Campbell, & Batter-
ham, 1998; Williams, Armstrong, & Powell, 2000).
In support of this, Mahon (2008) noted that low-
intensity training often results in a minimal training
stimulus response during paediatric interventions.
Nevertheless, several authors have suggested that
there are natural accelerated and decelerated periods
of development during maturation (Baquet, Van
Praagh, & Berthoin, 2003; Harro, Lintsi, & Viru,
1999; Viru et al., 1999). These are highly individua-
lized, which can be attributed in part to the
ﬂuctuating rates of anatomical, neurological, mus-
cular, metabolic, and hormonal development
(Naughton et al., 2000; Viru et al., 1999). Kobayashi
et al. (1978), Payne and Morrow, (1993), and
Baquet et al. (2003) suggest that there is an
exponential rise in peak oxygen uptake following
peak height velocity and puberty, in what Katch
(1983) and Rowland (1997) describe as the ‘‘trigger
hypothesis’’. Although there is discrepancy in the
literature, Viru et al. (1999) have reviewed several
longitudinal studies to show that peak development
of relative aerobic capacity (ml kg
occurs between 12 and 16 years in both boys and
girls. However, Viru et al. (1999) also reported that
cross-sectional research shows that the peak devel-
opment period for aerobic capacity occurs at 10–16
and 7–13 years in boys and girls, respectively.
Nevertheless, the credibility of the latter evidence
can be questioned because it is based on non-
causative observations. Furthermore, results from
previous studies suggest that children and adoles-
cents are signiﬁcantly less efﬁcient (related to aerobic
metabolism) in energy expenditure during move-
ment than adults and that children consume more
energy per unit of body mass during locomotion at a
given speed (Cavagna et al., 1983; De Jaeger et al.,
2001; Schepens et al., 2004). Plausible explanations
can be attributed to differences in body size, lack of
neuromuscular maturity, and an inability to effec-
tively deliver oxygen to the required muscles in
children, which become adult-like with increasing
growth and maturation (Cavagna, Franzetti, &
Fuchimoto, 1983; De Jaeger, Willems, & Heglund,
2001; Schepens, Bastien, Heglund, & Willems,
2004). However, it seems that the potential for
improving economy of movement and physical
performance is likely inﬂuenced by training as well.
However, few investigations have speciﬁcally ad-
dressed appropriate training prescription or identiﬁ-
cation of sensitive periods to enhance economy of
movement subsequent to improvements through
physical development (Naughton et al., 2000). It
might be postulated that overall economy of move-
ment will be continuously enhanced with physical
activity and exercise through childhood and adoles-
cence (Baquet et al., 2003).
After acknowledging this literature and when
focusing on the concept of ‘‘windows of opportu-
nity’’, Naughton et al. (2000) state that the growth-
related improvements from aerobic training in well-
trained male adolescent athletes (compared with
well-trained pre-adolescent males) relate to changes
in hormone secretions during maturation. Moreover,
Naughton et al. (2000) suggest that training aerobic
ﬁtness when there is a lack of circulating metabolites,
thus resulting in a reduced training adaptation
response, supports the ‘‘windows of trainability’’
concept of the LTAD model. For example, Weber
and colleagues (Weber, Kartodihardjo, & Klissouras,
1976) have suggested that there is a decreased
sensitivity to aerobic ﬁtness training response that
occurs in the middle of the peak height velocity
when compared with the years surrounding it.
Long-Term Athlete Development model 393
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Alternatively, some authors have suggested that most
sensitive training adaptations to aerobic ﬁtness
actually occur before peak height velocity, including
Rowland (1985) who identiﬁed a 10.1% and 8.8%
improvement in peak oxygen uptake during this
period in boys and girls, respectively. Thus it would
appear that there are discrepancies in the literature in
terms of when these actual ‘‘windows’’ occur.
Perhaps this discrepancy can be related to the fact
that much of the evidence for this ﬁtness component
is based on cross-sectional studies, which restricts
inferences due to methodological restraints. The lack
of longitudinal data is also coupled with the
imprecise assessment of training stimulus, which is
required to elicit peak development (Baquet et al.,
2003). Both Naughton et al. (2000) and Baquet et al.
(2003) conclude that the ﬁndings are obscured
further by genetic background and training load,
which are rarely reported. Therefore, attributing any
adaptive response in line with physical development
is ﬂawed due to the variation in the magnitude of the
stimulus. In addition, it appears that research has
focused on participants during pre-pubertal years
rather than adolescents, and has not accounted for
initial peak oxygen uptake values (Tolfrey et al.,
1998). Such a lack of the recognition of these
fundamental aspects limits the direct investigation
of the ‘‘windows of trainability’’ concept, and may
indeed mean that application by practitioners is
inappropriate at present.
Long-term studies that map changes in aerobic
capacity during growth and measure the inﬂuence
of physical activity or training concurrently are
required. As discussed previously, the complexity
of the research design to answer such a problem
may render the project impractical, and thus
progression in this area will perhaps not occur.
Nevertheless, until more comprehensive consistent
evidence is available, it is inappropriate to state
that young participants should only train aerobic
ﬁtness during prescribed ‘‘windows of opportu-
nity’’. Aerobic ﬁtness should be actively developed
throughout childhood and adolescence (Shephard,
Speed. Both boys and girls show similar sprint speed
during the ﬁrst decade of life (Borms, 1986; Malina
et al., 2004), with a period of accelerated adaptation
suggested to occur between the ages of 5 and 9 years
in both sexes (Borms, 1986; Viru et al., 1999). From
the age of 12 years, the rate of progression of speed
development is dramatically reduced in females
compared with males (Whitall, 2003), with the
arrival of the fourth puberty stage being suggested
to mark the end of maximal speed development in
girls not involved in sport (Szczesny & Coudert,
1993). This disparity between the sexes is attributed
to maturational changes in body dimensions and
composition (Beunen & Malina, 1988; Butterﬁeld,
Lehnhard, Lee, & Coladarci, 2004). A second period
of accelerated adaptation has been reported to occur
around the age of 12 years in girls and between 12
and 15 years in boys (Borms, 1986).
The development of speed throughout childhood
will be inﬂuenced by quantitative changes in muscle
cross-sectional area and length, biological and
metabolic changes, morphological alterations to the
muscle and tendon, neural/motor development, as
well as biomechanical and coordination factors. The
integration of all of these systems makes it difﬁcult to
identify precise mechanisms responsible for any
speed gains achieved throughout childhood. The
initial period of accelerated adaptation observed
before the end of the ﬁrst decade of life has been
suggested to be linked to the development of the
central nervous system and improved coordination
(Borms, 1986; Viru et al., 1999). This assumption is
supported by the rapid growth of the central nervous
system during the ﬁrst 7 years of life (Malina et al.,
2004), and the observation that coordination pat-
terns of locomotor skills reach adult levels by the
same age (Whitall, 2003).
Increased muscle size and length during adoles-
cence support a maturational inﬂuence on speed
development, although Butterﬁeld et al. (2004)
found no association between longitudinal growth
rates of height and body mass and improved running
speed in children aged 11–13 years. Although 2 years
may be considered brief for a longitudinal study, the
above ﬁndings may also reﬂect a limitation of the
current LTAD model, which relies on growth rates
to identify maturational status. Increases in muscle
substrates and enzymes associated with anaerobic
energy production provide another means for im-
proving speed immediately before and during the
teenage years (Eriksson, 1980). Physical properties of
the muscle and tendon architecture will also inﬂu-
ence the ability to produce speed. These properties
include the reported marked increases in the surface
area of the muscle–tendon junction from childhood
into adulthood, which is accompanied by a reduced
number of Golgi organs in the mature state (Ovalle,
1987). As a consequence of these changes in the
biomechanical properties of muscle and connective
tissue, a ten-fold increase in muscle–tendon stiffness
has been observed in the ﬁrst two decades of life
(Lin, Brown, & Walsh, 1997). Changes in muscle
stiffness will also be inﬂuenced by neural factors,
with ﬁring rates (Whitall, 2003), twitch times (Lin
et al., 1997), reﬂex muscle activity (Grosset, Mora,
Lambertz, & Perot, 2007), and co-activation
(Lambertz, Mora, Grosset, & Perot, 2003) all being
394 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
shown to develop through childhood in a manner
that would favour increased speed production.
The current LTAD model speculates that two
‘‘windows of opportunity’’ exist to maximize training
gains in childhood. These ‘‘windows’’ are related to
chronological age and occur at approximately 7–9
years in both boys and girls, with a second window
between 11 and 13 years in girls and between 13 and
15 years in boys. The fact that the second window is
staggered by 2 years between girls and boys can be
interpreted as more of a maturational, as opposed to
a chronological, ‘‘window of opportunity’’. A ma-
turational role in the second ‘‘window of opportu-
nity’’ is supported by Viru et al. (1999), who
speculated that speed training gains during this
period were related to hormone-dependent selective
hypertrophy of fast-twitch ﬁbres in both boys and
girls. Surprisingly, research examining the trainabil-
ity of speed during childhood is sparse. Venturelli
and colleagues (Venturelli, Bishop, & Pettene, 2008)
found that the magnitude of speed gains were similar
for pre-adolescent soccer players involved in coordi-
nation training and traditional straight-line sprint
training. This ﬁnding supports a role of coordination
and neural control in speed development prior to
maturation, although whether these factors are more
trainable during pre-adolescence is not known.
Philippaerts et al. (2006) reported that sprint speed
in youth footballers showed the largest gains around
the time of peak height velocity, suggesting a
combined training and maturational affect. How-
ever, the longitudinal data presented by Philippaerts
et al. (2006) showed a decline in sprint performance
in the 12 months preceding peak height velocity, and
any subsequent gains may simply have reﬂected a
correction of the previously impaired performance.
Improvements in speed around peak height velocity
may also be related to increased lower limb length,
reﬂecting an entity that is clearly not trainable. Rapid
periods of physical growth may disrupt motor
coordination in some individuals, a phenomenon
known as ‘‘adolescent awkwardness’’ (Beunen &
Malina, 1988; Philippaerts et al., 2006). However,
the timing and magnitude of this phenomenon is still
unknown and it is difﬁcult to evaluate if this
observation is being enshrined as ‘‘fact’’ when based
on limited empirical evidence.
While there is limited research available on the
trainability of speed throughout childhood, some
research has investigated possible mechanisms re-
sponsible for training gains during childhood. Sprint
training has been shown to increase concentrations
of substrates and enzymes utilized during anaerobic
metabolism in 11-year-olds (Eriksson, 1980) and
adolescent boys (Cadefau et al., 1990; Fournier
et al., 1982). However, the magnitude of the
training-induced change is reported to be below that
of adults and any adaptation is lost following a
detraining period (Fournier et al., 1982). The
magnitude of the response and rapid detraining
would suggest metabolic factors are unlikely to be
constrained to maximizing gains during a window of
opportunity in childhood. Sprint training has also
been shown to have a limited effect on catecholami-
nergic responses to sprint exercise in adolescent girls,
which disappears with detraining (Botcazou et al.,
2006). Therefore, any combined speed training and
maturational effects appear to have a limited
inﬂuence on the sympo-adrenal response. In a 6
month study of youth soccer players, Gravina et al.
(2008) reported a signiﬁcant correlation between
changes in testosterone concentrations and changes
in sprint performance. Although these ﬁndings
support a maturational relationship for improved
speed for players involved in a training programme,
the correlation was only modest (r ¼ 0.34, P 5 0.05)
and with 512% shared variance between the two
variables other factors need to be considered.
Identifying a single mechanism responsible for
improved speed during childhood is unlikely. In-
stead, a number of biological, neural, and biome-
chanical factors will inﬂuence the development of
speed. These factors may develop at different rates
for different individuals and may be linked to both
age and maturation. The trainability of factors
associated with speed development during childhood
Strength. The development of muscle strength is a
multi-faceted, performance-related ﬁtness compo-
nent that is underpinned by muscular, neural, and
mechanical factors (De Ste Croix, 2008). The
complex interaction of these components makes the
study of the increase in muscle strength during
growth and maturation challenging. As strength is an
essential component of most aspects of performance,
it is surprising that very little is known about the
factors associated with strength development during
childhood compared with the other ﬁtness compo-
nents discussed in this review. This may be
attributed to the difﬁculty in measuring internal
forces and the inherent methodological problems
associated with determining external force. As there
are no physiological markers that a maximal effort
has been given, the methodological and assessment
choices are critical in paediatric studies of muscle
strength (De Ste Croix, 2007). However, the
ﬁndings of studies on the age- and sex-associated
changes in strength are relatively consistent, espe-
cially for the lower limbs. Caution, however, 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 (De Ste
Long-Term Athlete Development model 395
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Strength increases in both boys and girls until
about the age of 14 years, when it begins to plateau in
girls and a spurt is evident in boys. By 18 years there
are few overlaps in strength between boys and girls,
although this simplistic model utilizing chronological
age as a marker for development in strength does not
take into account the individual timing and tempo of
growth and maturation (an issue seen with all the
ﬁtness components). The exact ages at which sex
differences become apparent appear to be both
muscle group and muscle action speciﬁc and data
have indicated that differences in upper body
strength between the sexes occur earlier than
differences in lower body strength (Gilliam, Villa-
nacci, Freedson, & Sady, 1979; Round, Jones,
Honour, & Nevill, 1999). What is less clear is the
complex interaction of factors that contribute to
strength (the production of force) during childhood
and adolescence. Few well-controlled longitudinal
studies have concurrently examined the inﬂuence of
known variables using appropriate statistical techni-
ques (De Ste Croix, Armstrong, Welsman, &
Sharpe, 2002; Round et al., 1999; Wood, Dixon,
Grant, & Armstrong, 2004). Most studies that have
determined maturation have shown that it does not
exert an independent effect when other factors, such
as stature and body mass, are accounted for (De Ste
Croix et al., 2002; Hansen, Klausen, & Muller,
1997; Maffulli, King, & Helms, 1994). Also, the
assumption that muscle cross-sectional area is the
most important parameter in strength development
throughout childhood and adolescence does not hold
when examined with other known variables (Deigh-
an, Armstrong, & De Ste Croix, 2003; De Ste Croix
et al., 2002). 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
(for a detailed explanation of the muscle moment
arm, see Wood et al., 2004).
Strength training is now deemed to be safe and
effective for children and adolescents when appro-
priately designed and supervised (Christou et al.,
2006; Falk & Tenenbaum, 1996). Well-established
guidelines for youth resistance training (e.g. Faigen-
baum et al., 2009; Stratton et al., 2004) recommend
resistance training for enhancement of muscular
strength in youths, with improvements in body
composition (Sothern et al., 2000) and motor
performance (Christou et al., 2006), and reductions
in injury (Faigenbaum et al., 2009) further advan-
tages. Research studies have demonstrated that
strength is trainable during childhood and adoles-
cence, with Faigenbaum and colleagues (2001)
reporting strength gains in children as young as 5
years. However, a large variation in strength gains
exists between studies, with improvements ranging
from 5.3% (Faigenbaum, Westcott, Loud, & Long,
1999) to 87.0% (Faigenbaum, Zaichkowsky, West-
cott, Micheli, & Fehlandt, 1993) in untrained
participants. Several factors may contribute to this
variation, including the baseline measure of strength,
the age range of participants, training programme
designs (e.g. frequency, volume, and intensity),
muscle group/action assessed, and exercises/assess-
ments used. These all make the evaluation of training
The LTAD model states that strength is always
trainable but recommends the optimal ‘‘window of
trainability’’ for boys is 12–18 months following peak
height velocity, while for girls it is immediately after
peak height velocity or at the onset of the menarche
(Balyi & Hamilton, 2004). However, research
examining the optimal ‘‘window of trainability’’ is
limited and there appear to be no longitudinal
strength training studies that have determined peak
height velocity and that have appropriately controlled
for growth and maturation. Only three studies
(Lillegard, Brown, Wilson, Henderson, & Lewis,
1997; Pfeiffer & Francis, 1986; Vrijens, 1978) could
be found that compared the trainability of strength
across different maturational ages. Vrijens (1978)
found greater arm and leg strength improvements in
a post-pubertal (16.8 years) group compared with a
pre-pubertal (10.5 years) group, who improved lower
back and abdominal strength to a greater degree
following an 8 week training programme. However,
both Lillegard et al. (1997) and Pfeiffer and Francis
(1986) found no differences in the percentage
magnitude of strength training response between
different maturational training groups. Therefore,
current research supporting the LTAD model’s
optimal ‘‘window of trainability’’ for strength is
speculative, with only one study concluding that
the strength training response is greater after pub-
erty. Based on current research, strength training can
be undertaken by children, as long as the programme
is designed and supervised by professionals. Further
research examining strength training gains against
biological age (age at peak height velocity; Mirwald,
Bailey, Cameron, & Rasmussen, 1981) are required
to determine if an optimal window of strength
trainability does exist. In addition, research should
also focus on the training variables (e.g.
volume, frequency, load, and rest periods) for
optimum strength training gains in children and
Power. Rapid developments in muscular power have
been established in pre-pubescent children between
the ages of 5 and 10 years (Branta, Haubenstricker,
Seefeldt, 1984). These periods of accelerated devel-
opment are largely attributable to enhanced neuro-
muscular coordination. A secondary spurt has been
396 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
associated with the onset of puberty in girls between
9 and 12 years, and in boys between the ages of 12
and 14 years (Beunen, 1997), with signiﬁcant
development in leg power at the ages of 14 and 15
years (Blanksby, Bloomﬁeld, Ackland, Elliott, &
Morton, 1994). The latter spurt is related to a
combination of hormonal, muscular, and mechanical
factors caused by the onset of puberty (as seen with
the other ﬁtness components). When aligning the
velocity curve of lower limb power development in
relation to peak height velocity, previous research has
identiﬁed an adolescent spurt beginning 1.5 years
before peak height velocity, and peaking 0.5–1.0 year
after peak height velocity (Beunen & Malina, 1988).
Like muscular strength, therefore, while accelera-
tions in muscular power may occur around the time
of peak height velocity, peak muscular power would
appear to coincide more readily with peak weight
velocity, suggesting that both increases in muscle
mass and motor unit activation are strongly linked to
muscular power. Butterﬁeld et al. (2004) reported a
strong correlation between vertical jump height and
the growth rates of their pre-adolescent sample
(r ¼ 0.95, P 5 0.05). Growth-related changes in both
leg length and muscle mass were associated with
increased vertical jump height, and these structural
changes were deemed to override any negative
effects of the concomitant increase in body mass
(Butterﬁeld et al., 2004).
As with a number of other physical components,
sex-related differences appear to exist in muscular
power from pre- to post-adolescence, with differ-
ences becoming more apparent at the age of 14 years
onwards, as a result of the increased leg length and
muscle volume in males (Temfemo, Hugues, Char-
don, Mandengue, & Ahmaidi, 2009). Observations
of cross-sectional data show sex-related differences
in mean countermovement jump height scores of 7-
to 11-year-old girls and boys (Isaacs, 1998). Butter-
ﬁeld et al. (2004) reported differences in their
baseline measures of vertical jump height between
boys and girls aged 11–13 years, and also highlighted
that the growth rate of jumping for boys signiﬁcantly
exceeded that of girls by 1.91 cm every 4 months
over a 9 month period. Research has revealed
signiﬁcant differences between stages of sexual
maturity and vertical jump height performance in
boys (11–16 years), even when the inﬂuences of body
mass and stature were removed (Jones, Hitchen, &
Stratton, 2000). However, differences between sex-
ual maturity stages and vertical jump performance
were not statistically signiﬁcant among girls. But the
greater effect of sexual maturation on muscular
power output in boys during the adolescent growth
spurt highlights the likely attributable increases in
androgen concentrations – notably growth hormone,
testosterone, and thyroid hormone – between boys
and girls (Rogol, 1996; Viru et al., 1999). More
recently, a neuromuscular spurt was evident in male
athletes characterized by an increase in both vertical
jump height and the ability to attenuate landing
forces (Quatman, Ford, Myer, & Hewett, 2006).
Within the female sample, a reduction in both
vertical jump height and take-off force highlighted
the contrasting effects of maturation on lower limb
In addition to muscle cross-sectional area (Jacobs,
Sjodin, & Svane, 1982), neurological changes
(Blimkie & Bar-Or, 1996), motor coordination
(Isaacs, 1998), ﬁbre type composition (Mero,
Jaakkola, & Komi, 1991), and prior training experi-
ence (Bencke et al., 2002) have all been postulated to
be determining mechanisms for lower limb explosive
strength in youths. Despite these suggestions, limited
data exist for the combined effects of maturation and
trainability on lower limb muscular power adapta-
tions. Chiodera et al. (2008) implemented a 33 week,
three lessons per week motor abilities physical educa-
tion programme for boys and girls between the ages of
6 and 10 years. Results revealed signiﬁcant improve-
ments (6–10 cm; P 5 0.01) in long jump distance for
all ages and for both sexes, suggesting that trainability,
as well as growth and maturational factors, may have a
positive effect on power development throughout
childhood in both males and females. Other studies
have reported statistical differences between playing
ability and vertical and horizontal jump tests (Gissis,
Kalapotharakos, Sotiropoulos, Komsis, & Manolo-
poulos, 2006; Vaeyens et al., 2006), and signiﬁcant
improvements in lower limb muscular power follow-
ing a 6 week combination of plyometrics and
resistance training (Faigenbaum et al., 2007). How-
ever, without longitudinal data for corresponding
measures of maturity status and muscular power, the
existence of any ‘‘windows of opportunity’’ remains
unclear, as does the question of whether or not
adaptations are greater for those athletes who are
exposed to power-based training during, as opposed to
outside of, any such ‘‘windows’’.
The current LTAD model provides no indication
of a ‘‘window of opportunity’’ for power develop-
ment during childhood. This may be due to the fact
that as the product of force (strength) and velocity
(speed), the ‘‘windows of opportunity’’ have already
been included in the model for the component parts
of power production. However, given the importance
of muscular power for athletic success, it may be
appropriate to consider the most appropriate period
during which to train for power during childhood.
Owing to the minimal number of longitudinal-based
studies examining the interaction of growth, matura-
tion, and trainability on muscular power, it is
difﬁcult to identify whether a window of opportunity
exists to maximize power development.
Long-Term Athlete Development model 397
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Windows of opportunity
Undeniably, the basis of the LTAD model centres
around annual training and competition design,
which have been well documented previously (Bom-
pa, 1995; Harre, 1982; Norris & Smith, 2002; Wilke
& Madsen, 1986). However, the model also maps
physiological adaptations associated with growth and
maturation, through maximizing training ‘‘windows
of opportunity’’ as repeatedly highlighted throughout
this review. Essentially, these are critical/sensitive
periods for accelerated development of motor
performance based on a suitable training stimulus
during appropriate maturational time periods (Gu-
zalovsky, 1977). Nevertheless, as noted above (in
several previous sections), the actual concept of the
development periods related to increased adaptive
properties to factors stimulating development (i.e.
training and exercise), as well as the potential
negative implications, require further scientiﬁc ver-
iﬁcation. It seems that the appropriate application of
training in line with maturation highlighted above
may have a signiﬁcant inﬂuence on peak perfor-
mance through cell, tissue, organ, and whole-system
specialization (Balyi & Hamilton, 2004; Wenger,
McFayden, & McFayden, 1996). Certainly in the
applied literature it has been documented that
conducting a training intervention outside of a
‘‘window of opportunity’’ will result in few if any
training gains and may actually be detrimental to
future adaptations (Zaichkowsky, Zaichkowsky, &
Martinek, 1980), but there is a clear lack of
supporting evidence for such an assertion.
The present authors’ acknowledge the difﬁculties
in the quantiﬁcation of physical activity and training
in young participants, as well as controlling this
during applied investigations. This in part can
explain why there is a lack of agreement in the
literature. Loko and colleagues (Loko, Sikkut, &
Aule, 1996) noted that there is evidence to suggest
that the best effect of training and the development of
performance capabilities is achieved when natural
growth is at its peak. However, paradoxically there is
a possible consequence that the full potential of the
individual is not achieved when early specialization
and intensive training occur during these ‘‘windows
of opportunity’’. Without supportive and objective
data to help conﬁrm/reject these ideas, inferring any
optimal training recommendations for successful
athletic pathways for young participants is perhaps
unsuitable. It is the opinion of the present authors
that this needs to be made clearer to coaches and
practitioners by national governing bodies.
Notwithstanding the empirical issues, the actual
terms of reference for ‘‘window of opportunity’’
require clariﬁcation. It seems a ‘‘critical period’’,
related to exercise training, is an opening to
effectively exploit a unique situation, which is vital
to adhere to, otherwise full athletic potential will not
be achieved. Whereas the term ‘‘sensitive period’’
implies an opening when extra gains may be
expected for the same efforts. Based upon this
strategy, it is clear that implications to the use of
such labels, together with signiﬁcant consequences
for important constructs such as specialization,
should be considered too. Furthermore, the term
‘‘window’’ suggests that the periods open and close,
when in fact they may open and remain so on to and
throughout adulthood (Viru et al., 1999).
In short, with issues related to deﬁnition and the
obvious lack of objective evidence, the authors’ belief
is that the proposition that if young participants do
not utilize these ‘‘windows of opportunity’’ they will
never reach maximum athletic is unjustiﬁed.
Furthermore, when utilizing fundamental training
principles within a long-term periodized plan, the
period of a ‘‘training emphasis’’ should be presented.
Again, coaches and practitioners should be made
more aware of the importance of training to advance
all ﬁtness components throughout childhood and
adolescence during non-sensitive periods as well,
principally because of different individual maturation
development rates and all components are trainable
to some extent (Suslov, 2002). By doing so this
should further help coaches avoid issues around early
specialization, and optimize general athletic devel-
opment of young performers.
Summary and implications
A number of studies have identiﬁed the numerous
physical developmental processes that occur during
childhood and adolescence and how they might
inﬂuence short- and long-term athletic performance
(Baquet et al., 2003; Boisseau & Delamarche, 2000;
Naughton et al., 2000; Viru et al., 1999). The most
prominent ideology to help to optimize long-term
athletic performance preparation in line with this is the
LTAD model (Balyi & Hamilton, 2004). This model
has received supported in contemporary coaching
texts (Balyi & Stafford, 2005; Balyi & Williams, 2009).
Certainly, the model succeeds in offering practitioners
a coaching framework using plausible principles.
However, from the components reviewed in this paper
(physical literacy, aerobic and anaerobic perfor-
mance), there is little evidence to support the LTAD
claims, possibly due to the number of physiological
factors that inﬂuence performance. Similarly, Norris
and Smith (2002) correctly state that the most
essential component of an effective training pro-
gramme is the concept of individualization. This
appears to be a further limitation of the LTAD model
(Balyi & Hamilton, 2004), even with physiological age
classiﬁcations due to their own limitations (Beunen,
398 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
1990; Janz & Mahoney, 1997). Moreover, Viru et al.
(1999) concisely state that the lack of evidence
between athletic performance and trainability against
ontogenetic development make any conclusions in-
accurate, particularly for the notion of ‘‘windows of
opportunity’’. Similarly, although such information
has been applied to speciﬁc physiological development
and training practices for children and adolescents, it
appears that there is a lack of consensus on the impact
of such hormonal and metabolic changes within
review articles (Boisseau & Delamarche, 2000;
Naughton et al., 2000). This is primarily due to the
practical issues and restrictions surrounding paedia-
tric research (Boisseau & Delamarche, 2000).
A key rationale for this review is how the LTAD
model is currently being understood and applied by
coaches and practitioners. It is the opinion of the
authors that coaches should be better educated in
how to interpret and use the information within the
model, in light of its positive and negative issues.
Subjectively, it appears that the model has been
widely prescribed to date, but it seems the knowledge
transfer of the generic principles that make up the
model are not being disseminated to allow coaches to
comprehend and adapt the model to suit the
individual needs of their own athletes. Furthermore,
the model would be more suitable if it were to be
more holistically orientated, encompassing some of
the key interdisciplinary perspectives seen elsewhere
(Bailey et al., 2010).
Therefore, while it should be clearly stated that the
LTAD model has advanced coaches’ and practi-
tioners’ understanding of the importance of physiolo-
gical principles and biological maturation alongside
training young athletes, there are many unexplained/
unsupported premises that undermine it. Preliminary
research to help practitioners to better understand
fundamental development issues of children and
adolescents is urgently required. Whether a situation
is reached whereby an evaluation of the application of
the model is conducted remains uncertain. What is
more certain is that future recommendations to help
enhance physical athletic performance from infant to
adult must be based on empirical evidence (Beunen &
Malina, 1996). With this in mind, we recommend to
key sporting stakeholders that they should look to
advance the scientiﬁc underpinning of their recom-
mendations by supporting appropriate applied scien-
tiﬁc investigations to enhance our understanding of
developing the youth athlete.
Armstrong, N., & Welsman, J. R. (1994). Assessment and
interpretation of aerobic ﬁtness in children and adolescents.
Exercise and Sport Sciences Reviews, 22, 435–476.
Arnold, P. J. (1979). Meaning in movement, sport and physical
education. London: Heinemann.
Badminton England (2006). Long Term Athlete Development.
Leeds: Coachwise Ltd.
Bailey, R. P., Collins, D., Ford, P. A., MacNamara, A
G., & Toms, M. (2010). Participant development in sport: An
academic literature review. Commissioned report for Sports
Coach UK. Leeds: Sports Coach UK.
Balyi, I., & Hamilton, A. (2004). Long-Term Athlete Development:
Trainability in children and adolescents. Windows of opportunity.
Optimal trainability. Victoria, BC: National Coaching Institute
British Columbia & Advanced Training and Performance Ltd.
Balyi, I., & Stafford, I. (2005). Coaching for Long-Term Athlete
Development. Leeds: Coachwise UK.
Balyi, I., & Way, R. (1995). Long-term planning for athlete
development: The training to train phase. BC Coach (Canada),
Fall, pp. 2–10.
Balyi, I., & Williams, C. A. (2009). Coaching the young developing
performer. Leeds: Coachwise UK.
Baquet, G., Van Praagh, E., & Berthoin, S. (2003). Endurance
training and aerobic ﬁtness in young people. Sports Medicine,
Barnett, L. M., van Beurden, E., Morgan, P. J., Brooks, L. O.,
Avigdor Zask, A., & Beard, J. R. (2009). Six year follow-up of
students who participated in a school-based physical activity
intervention: A longitudinal cohort study. International Journal
of Behavioral Nutrition and Physical Activity, 6 (48) (DOI:
Bencke, J., Damsgaard, R., Saekmose, A., Jorgensen, P.,
Jorgensen, K., & Klausen, K. (2002). Anaerobic power and
muscle strength characteristics of 11 year old elite and non-elite
boys and girls from gymnastics, team handball, tennis and
swimming. Scandinavian Journal of Medicine and Science in
Sports, 12, 171–178.
Beunen, G. (1990). Biological age in pediatric exercise research.
In O. Bar-Or (Ed.), Advances in pediatric sport sciences, Vol III:
Biological issues (pp. 1–39). Champaign, IL: Human Kinetics.
Beunen, G. P. (1997). Muscular strength development in children
and adolescents. In K. Froberg, O. Lammert, H. S. Hansen, &
C. J. R. Blimkie (Eds.), Children and exercise XVIII: Exercise and
ﬁtness – beneﬁts and risks (pp. 193–207). Odense: Odense
Beunen, G. P., & Malina, R. M. (1988). Growth and physical
performance relative to the timing of the adolescent spurt.
Exercise and Sport Sciences Reviews, 16, 503–540.
Beunen, G., & Malina, R. M. (1996). Growth and biological
maturation: Relevance to athletic performance. In O. Bar-Or
(Ed.), The child and adolescent athlete (pp. 3–24). Oxford:
Blanksby, B. A., Bloomﬁeld, J., Ackland, T. R., Elliott, B. C., &
Morton, A. R. (1994). Athletics, growth and development in
children. Camberwell: Harwood Academic.
Blimkie, C. J. R., & Bar-Or, O. (1996). Trainability of muscle
strength, power and endurance during childhood. In O. Bar-Or
(Ed.), The child and adolescent athlete (pp. 113–129). Oxford:
Boisseau, N., & Delamarche, P. (2000). Metabolic and hormonal
responses to exercise in children and adolescents. Sports
Medicine, 30, 405–422.
Bompa, T. (1995).
From childhood to champion athlete. West
Sedona, AZ: Veritas Publishing.
Borms, J. (1986). The child and exercise: An overview. Journal of
Sports Sciences, 4, 3–20.
Botcazou, M., Zouhal, H., Jacob, C., Gratas-Delamarche, A.,
Berthon, P. M., Bentue´-Ferrer, D. et al. (2006). Effect of
training and detraining on catecholamine responses to sprint
exercise in adolescent girls. European Journal of Applied
Physiology, 97, 68–75.
Long-Term Athlete Development model 399
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Bouchard, C., Malina, R. M., & Pe´russe, L. (1997). Genetics of
ﬁtness and physical performance. Champaign, IL: Human
Bouffard, M., Watkinson, E. J., Thompson, L. P., Dunne, J. L.
C., & Romanow, S. K. E. (1996). A test of the activity deﬁcit
hypothesis with children with movement difﬁculties. Adapted
Physical Activity Quarterly, 13, 61–73.
Branta, C., Haubenstricker, J., & Seefeldt, V. (1984). Age changes
in motor skills during childhood and adolescence. Exercise and
Sport Sciences Reviews, 12, 467–520.
British Gymnastics (2006). Long Term Athlete Development. Leeds:
Burgess, D. J., & Naughton, G. A. (2010). Talent development in
adolescent team sports: A review. International Journal of Sports
Physiology and Performance, 5, 103–116.
Butterﬁeld, S. A., Lehnhard, R., Lee, J., & Coladarci, T. (2004).
Growth rates in running speed and vertical jumping by boys
and girls ages 11–13. Perceptual and Motor Skills, 99, 225–234.
Cadefau, J., Casademont, J., Grau, J. M., Ferna´ndez, J., Balaguer,
A., Vernet, M. et al. (1990). Biochemical and histochemical
adaptation to sprint training in young athletes. Acta Physiologica
Scandinavica, 140, 341–351.
Cavagna, G. A., Franzetti, P., & Fuchimoto, T. (1983). The
mechanics of walking in children. Journal of Physiology, 343,
Chiodera, P., Volta, E., Gobbi, G., Milioli, M. A., Mirandola, P.,
Bonetti, A. et al. (2008). Speciﬁcally designed physical exercise
programs improve children’s motor abilities. Scandinavian
Journal of Medicine and Science in Sports, 18, 179–187.
Christou, M., Smilios, I., Sotiropoulos, K., Volaklis, K., Pilianidis,
T., & Tokmakidis, S. (2006). Effects of resistance training on
the physical capacities of adolescent soccer players. Journal of
Strength and Conditioning Research, 20, 783–791.
Collins, D., Ford, P. A., MacNamara, A
., Pearce, G., & Toms, M.
(2010). Participant development in sport: An academic literature
review. Leeds: Sports Coach UK/Sport Northern Ireland.
Cratty, B. J. (1986). Perceptual motor development in infants and
children (3rd edn.). Englewood Cliffs, NJ: Prentice-Hall.
Deighan, M. A., Armstrong, N., & De Ste Croix, M. B. A. (2003).
Peak torque per MRI-determined cross-sectional area of knee
extensors and ﬂexors in children, teenagers and adults. Journal
of Sports Sciences, 21, 236.
De Jaeger, D., Willems, P. A., & Heglund, N. C. (2001). The
energy cost of walking in children. European Journal of
Physiology, 441, 538–543.
Deli, E., Bakle, I., & Zachopoulou, E. (2006). Implementing
intervention movement programmes for kindergarten children.
Journal of Early Childhood Research, 4, 5–18.
Dennis, W. (1960). Causes of retardation among institutional
children: Iran. Journal of Genetic Psychology
, 96, 47–59.
Derri, V., Tsapakidou, A., Zachopoulou, E., & Kioumourtzoglou,
E. (2001). Effect of a music and movement programme on
development of locomotor skills by children 4 to 6 years of age.
European Journal of Physical Education, 20, 301–313.
De Ste Croix, M. B. A. (2007). Advances in paediatric strength
assessment: Changing our perspectives on strength develop-
ment. Journal of Sports Science and Medicine, 6, 292–304.
De Ste Croix, M. B. A. (2008). Muscle strength. In N. Armstrong
& W. Van Mechlen (Eds.), Paediatric exercise science and medicine
(pp. 199–211). Oxford: Oxford University Press.
De Ste Croix, M. B. A., Armstrong, N., Welsman, J. R., & Sharpe,
P. (2002). Longitudinal changes in isokinetic leg strength in
10–14 year olds. Annals of Human Biology, 29, 50–62.
England and Wales Cricket Board (2005). Planning for long term
success: The long term athlete development model for cricket.
Eriksson, B. O. (1980). Muscle metabolism in children – a review.
Acta Paediatrica Scandinavica, 283 (suppl.), 20–28.
Faigenbaum, A. D., Glover, S., O’Connell, J., LaRosa Loud, R.,
& Westcott, W. (2001). The effects of different resistance
training protocols on upper body strength and endurance
development in children. Journal of Strength and Conditioning
Research, 15, 459–465.
Faigenbaum, A. D., Kraemer, W. J., Blimkie, C. J. R., Jeffreys, I.,
Micheli, L. J., Nitka, M. et al. (2009). Youth resistance
training: Updated position statement paper from the National
Strength and Conditioning Association. Journal of Strength and
Conditioning Research, 23 (5, suppl.), S60–S79.
Faigenbaum, A. D., McFarland, J. E., Keiper, F. B., Tevlin, W.,
Ratamess, N. A., Kang, J. et al. (2007). Effects of a short-term
plyometric and resistance training program on ﬁtness in boys age
12 to 15 years. Journal of Sports Science and Medicine, 6, 519–525.
Faigenbaum, A. D., Westcott, W. L., Loud, R. L., & Long, C.
(1999). The effects of different resistance training protocols on
muscular strength and endurance development in children.
Pediatrics, 104, 1–7.
Fehlandt, A. (1993). The effects of a twice per week strength
training program on children. Pediatric Exercise Science, 5, 339–346.
Falk, B., & Tenenbaum, G. (1996). The effectiveness of resistance
training in children: A meta-analysis. Sports Medicine, 22, 176–
Flinchum, B. M. (1975). Motor development in early childhood: A
guide for movement education with ages 2 to 6. St. Louis, MO: C.
Fournier, M., Ricci, J., Taylor, A., Ferguson, R., Montpetit, R., &
Chaltman, B. (1982). Skeletal muscle adaptation in adolescent
boys: Sprint and endurance training and detraining. Medicine
and Science in Sports and Exercise, 14, 453–456.
Gabbard, C. (1992). Lifelong motor development. Bubuque, IA:
Gallahue, D., & Donnelly, F. (2003).Development of physical education
for all children (4th edn.). Champaign, IL: Human Kinetics.
Gallahue, D. L., & Ozmun, J. C. (1998). Understanding motor
New York: McGraw-Hill.
Gilliam, T. B., Villanacci, J. F., Freedson, P. S., & Sady, S. P.
(1979). Isokinetic torque in boys and girls ages 7 to 13: Effect of
age, height and weight. Research Quarterly for Exercise and Sport,
Gissis, I., Kalapotharakos, V. I., Sotiropoulos, A., Komsis, G., &
Manolopoulos, E. (2006). Strength and speed characteristics of
elite, sub-elite, and recreational young soccer players. Research
in Sports Medicine, 14, 205–214.
Graf, C., Koch, B., Falkowski, G., Jouck, S., Christ, H.,
Staudenmaier, K. et al. (2005). Effects of a school based
intervention on BMI and motor abilities in childhood. Journal of
Sports Science and Medicine, 4, 291–299.
Gravina, L., Gil, S. M., Ruiz, F., Zubero, J., Gil, J., & Irazusta, J.
(2008). Anthropometric and physiological differences between
ﬁrst team and reserve soccer players aged 10–14 years at the
beginning and end of the season. Journal of Strength and
Conditioning Research, 22, 1308–1314.
Grosset, J.-F., Mora, I., Lambertz, D., & Pe´rot, C. (2007). Changes
in stretch reﬂexes and muscle stiffness with age in prepubescent
children. Journal of Applied Physiology, 102, 2352–2360.
Guzalovsky, A. A. (1977). Physical education of schoolchildren in
critical periods of development. Teoria I praktika ﬁzicheskoi
kulturo˜, 7, 37–39. Cited in Viru et al. (1999).
Hands, B., & Larkin, D. (2006). Physical ﬁtness differences in
children with and without motor learning difﬁculties. European
Journal of Special Needs Education, 21, 447–456.
Hansen, L., Klausen, K., & Muller, J. (1997). Assessment of
maturity status and its relation to strength measurements. In N.
Armstrong, B. J. Kirby, & J. Welsman (Eds.). Children and
exercise XIX: Promoting health and well-being (pp. 325–330).
London: E&FN Spon.
400 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Harre, D. (1982). Principles of sports training. Berlin: Sportsverlag.
Harro, M., Lintsi, M., & Viru, A. (1999). Maximal oxygen uptake
in age 4 to 10: Relation to echocardiographic measures and
motor activity (unpublished). Cited in Viru et al. (1999).
Higgs, C., Balyi, I., Way, R., Cardinal, C., Norris, S., & Bluechardt,
M. (2008). Developing physical literacy: A guide for parents of
children aged 0 to 12. Vancouver, BC: Canadian Sports Centres.
Ingle, L., Sleap, M., & Tolfrey, K. (2006). The effect of a complex
training and detraining programme on selected strength and
power variables in early pubertal boys. Journal of Sports Sciences,
Isaacs, L. D. (1998). Comparison of the Vertec and Just Jump
systems for measuring height of vertical jump by young
children. Perceptual and Motor Skills, 86, 659–663.
Jacobs, I., Sjodin, B., & Svane, B. (1982). Muscle ﬁber type, cross-
sectional area and strength in boys after 4 years’ endurance
training. Medicine and Science in Sports and Exercise, 14, 123.
Janz, K. F., & Mahoney, L. T. (1997). Three-year follow-up of
changes in aerobic ﬁtness during puberty: The Muscatine
study. Research Quarterly for Exercise and Sport, 68, 1–9.
Jones, A. M., & Carter, H. (2000). The effect of endurance
training on parameters of aerobic ﬁtness. Sports Medicine, 29,
Jones, M. A., Hitchen, P. J., & Stratton, G. (2000). The
importance of considering biological maturity when assessing
physical ﬁtness measures in girls and boys aged 10 to 16 years.
Annals of Human Biology, 27, 57–65.
Katch, V. L. (1983). Physical conditioning of children. Journal of
Adolescent Health Care, 3, 241–246.
Kobayashi, K., Kitamura, K., Miura, M., Sodeyama, H., Murase,
Y., Miyashita, M. et al. (1978). Aerobic power as related to
body growth and training in Japanese boys: A longitudinal
study. Journal of Applied Physiology, 44, 666–672.
Lambertz, D., Mora, I., Grosset, J. F., & Perot, C. (2003).
Evaluation of musculotendinous stiffness in prepubertal chil-
dren and adults, taking into account muscle activity. Journal of
Applied Physiology, 95, 64–72.
Lillegard, W. A., Brown, E. W., Wilson, D. J., Henderson, R., &
Lewis, E. (1997). Efﬁcacy of strength training in prepubescent
males and females: Effects of gender and maturity. Paediatric
Rehabilitation, 1, 147–157.
Lin, J. P., Brown, J. K., & Walsh, E. G. (1997). Soleus muscle
length, stretch reﬂex excitability, and the contractile properties
of muscle in children and adults: A study of the functional joint
angle. Developmental Medicine and Child Neurology, 39, 469–
Loko, J., Sikkut, T., & Aule, R. (1996). Sensitive periods in
physical development. Modern Athlete and Coach, 34 (2), 26–29.
Maffulli, N., King, J. B., & Helms, P. (1994). Training in elite
youth athletes: Injuries, ﬂexibility and isometric strength. British
Journal of Sports Medicine, 28, 123–136.
Mahon, A. D. (2008). Aerobic training. In N. Armstrong & W.
Van Mechlen (Eds.), Paediatric exercise science and medicine (pp.
273–286). Oxford: Oxford University Press.
Malina, R. M., Bouchard, C., & Bar-Or, O. (2004). Growth,
maturation and physical activity. Champaign, IL: Human Kinetics.
McClenaghan, B. A., & Gallahue, D. L. (1978). Fundamental
movement: A developmental and remedial approach. Eastbourne:
McGraw, M. B. (1935). Growth: A study of Johnny and Jimmy.
New York: Appleton-Century-Crofts.
McGraw, M. B. (1959). Development of motor function in early age. In
Proceedings of the 12th Jubelious International Congress of Sports Medicine
(pp. 560–561). Moscow: Medgiz. Cited in Viru et al. (1999).
Mero, A., Jaakkola, L., & Komi, P. V. (1991). Relationships
between muscle ﬁbre characteristics and physical performance
capacity in trained athletic boys. Journal of Sports Sciences, 9,
Mirwald, R. L., Bailey, D. A., Cameron, N., & Rasmussen, R. L.
(1981). Longitudinal comparison of aerobic power in active and
inactive boys aged 7.0 to 17.0 years. Journal of Applied
Physiology, 44, 666–672.
Naughton, G., Farpour-Lambert, N., Carlson, J., Bradney, M., &
Van Praagh, E. (2000). Physiological issues surrounding the
performance of adolescent athletes. Sports Medicine, 30, 309–
Norris, S. R., & Smith, D. J. (2002). Planning, periodization, and
sequencing of training and competition: The rationale for a
competently planned, optimally executed training and competi-
tion program, supported by a multidisciplinary team. In M.
Kellmann (Ed.), Enhancing recovery: Preventing underperformance
in athletes (pp. 119–141). Champaign, IL: Human Kinetics.
Okely, A. D., Booth, M. L., & Chey, T. (2004). Relationships
between body composition and fundamental movement skills
among children and adolescents. Research Quarterly for Exercise
and Sport, 75, 238–247.
Okely, A. D., Booth, M. L., & Patterson, J. W. (2001a).
Relationship of physical activity to fundamental movement
skills among adolescents. Medicine and Science in Sports and
Exercise, 33, 1899–1904.
Okely, A. D., Booth, M. L., & Patterson, J. W. (2001b).
Relationship of cardiorespiratory endurance to fundamental
movement skill proﬁciency among adolescents. Pediatric Ex-
ercise Science, 13, 380–391.
Ovalle, W. K. (1987). The human muscle–tendon junction: A
morphological study during normal growth and at maturity.
Anatomy and Embryology, 176, 281–294.
Payne, V. G., & Morrow, J. R. (1993). The effect of physical
training on pre-pubescent
: A meta-analysis. Research
Quarterly for Exercise and Sport, 64, 305–313.
Pfeiffer, R., & Francis, R. (1986). Effects of strength training on
muscle development in prepubescent, pubescent and postpu-
bescent males. Physician and Sportsmedicine, 14, 134–143.
Philippaerts, R. M., Vaeyens, R., Janssens, M., Van Renterghem,
B., Matthys, D., Craen, R. et al. (2006). The relationship
between peak height velocity and physical performance in youth
soccer players. Journal of Sports Sciences, 24, 221–230.
Phillips, E., Davids, K., Renshaw, I., & Portus, M. (2010). Expert
performance in sport and the dynamics of talent development.
Sports Medicine, 40, 271–283.
Platonov, Y. N. (1988). L’entrainement sportif: Theorie et methode.
Paris: Ed. EPS.
Quatman, C. E., Ford, K. R., Myer, G. D., & Hewett, T. E.
(2006). Maturation leads to gender differences in landing force
and vertical jump performance. American Journal of Sports
Medicine, 34, 806–813.
Rabinowicz, T. (1986). The differentiated maturation of the
cerebral cortex. In F. Falkner & J. Tanner (Eds.), Human
growth: A comprehensive treatise, Vol. 2. Postnatal growth:
Neurobiology (2nd edn., pp. 385–410). New York: Plenum.
Riordan, J. (1977). Sport in Soviet society. Cambridge: Cambridge
Rogol, A. D. (1996). Growth and growth hormone secretion at
puberty in males. In C. G. Blimkie & O. Bar-Or (Eds.), New
horizons in pediatric exercise science (pp. 39–76). Champaign, IL:
Round, J. M., Jones, D. A., Honour, J. W., & Nevill, A. M.
(1999). Hormonal factors in the development of differences in
strength between boys and girls during adolescence: A long-
itudinal study. Annals of Human Biology, 26, 49–62.
Rowland, T. W. (1985). Aerobic response to endurance training in
prepubescent children: A critical analysis. Medicine and Science
in Sports and Exercise, 17, 493–497.
Rowland, T. W. (1997). The ‘‘trigger hypothesis’’ for aerobic
trainability a 14-year follow-up (editorial). Pediatric Exercise
Science, 9, 1–9.
Long-Term Athlete Development model 401
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011
Schepens, B., Bastien, G. J., Heglund, N. C., & Willems, P. A.
(2004). Mechanical work and muscular efﬁciency in walking
children. Journal of Experimental Biology, 207, 587–596.
Shephard, R. J. (1992). Effectiveness of training programmes for
pubescent children. Sports Medicine, 13, 194–213.
Sothern, M., Loftin, J., Udall, J., Suskind, R., Ewing, T., Tang, S.
et al. (2000). Safety, feasibility and efﬁcacy of a resistance
training program in preadolescent obese youth. American
Journal of Medical Sciences, 319, 370–375.
Stratton, G., Jones, M. A., Fox, K. R., Tolfrey, K., Harris, J.,
Maffulli, N. et al. (2004). BASES position statement on
guidelines for resistance exercise in young people. Journal of
Sports Sciences, 22, 383–390.
Suslov, F. (2002). About the sensitive age periods in the
development of physical capacities. Modern Athlete and Coach,
Szczesny, S., & Coudert, J. (1993). Changes in running speed and
endurance among girls during puberty. In J. A. P. Day & J. W.
Duguet (Eds.), Kinanthropometry IV (pp. 268–284). London:
Szmodis, I. (1991). Suggested emphasis in training with the growing
athlete. The Scottish International Education Trust Lecture.
Temfemo, A., Hugues, J., Chardon, K., Mandengue, S.-H., &
Ahmaidi, S. (2009). Relationship between vertical jumping
performance and anthropometric characteristics during growth
in boys and girls. European Journal of Pediatrics, 168, 457–464.
Tihanyi, J. (1990). Long term planning for young athletes: An
overview of the inﬂuences of growth, maturation and development.
Sudbury, ONT: Laurentian University.
Tolfrey, K., Campbell, I. G., & Batterham, A. M. (1998). Aerobic
trainability of prepubertal boys and girls. Pediatric Exercise
Science, 10, 248–263.
Vaeyens, R., Malina, R. M., Janssens, M., Van Renterghem, B.,
Bourgois, J., Vrijens, J. et al. (2006). A multidisciplinary
selection model for youth soccer: The Ghent Youth Soccer
Project. British Journal of Sports Medicine, 40, 928–934.
Venturelli, M., Bishop, D., & Pettene, L. (2008). Sprint training in
preadolescent soccer players. International Journal of Sports
Physiology and Performance, 3, 558–562.
Viru, A., Loko, J., Harro, M., Volver, A., Laaneots, L., & Viru, M.
(1999). Critical periods in the development of performance
capacity during childhood and adolescence. European Journal of
Physical Education, 4, 75–119.
Vrijens, J. (1978). Muscle development in the pre and post
pubescent age. Medicine in Sport, 11, 152–158.
Weber, G., Kartodihardjo, W., & Klissouras, V. (1976). Growth
and physical training with reference to heredity. Journal of
Applied Physiology, 40, 211–215.
Wenger, H. A., McFayden, P. F., & McFayden, R. A. (1996).
Physiological principles of conditioning. In J. E. Zachazewski,
D. J. Magee, & W. S. Quillen (Eds.), Athletic injury and
rehabilitation (pp. 189–205). Philadelphia, PA: W. B. Saunders.
Whitehead, M. E. (2001). The concept of physical literacy.
European Journal of Physical Education, 6, 127–138.
Whitehead, M. E. (2004). Physical literacy – a debate. Unpublished
paper given at the pre-Olympic Congress, Thessaloniki.
Whithall, J. (2003). Development of locomotor co-ordination and
control in children. In G. J. P. Savelsberg, K. Davids, & J. Van
der Kamp (Eds.), Development of movement coordination in
children: Applications in the ﬁeld of ergonomics, health sciences and
sport (pp. 251–270). London: Routledge.
Wilke, K., & Madsen, O. (1986). Coaching the young swimmer.
Williams, C. A., Armstrong, N., & Powell, J. (2000). Aerobic
responses of prepubertal boys to two modes of training. British
Journal of Sports Medicine, 34, 168–173.
Wood, L. E., Dixon, S., Grant, C., & Armstrong, N. (2004).
Elbow ﬂexion and extension strength relative to body size or
muscle size in children. Medicine and Science in Sports and
Exercise, 36, 1977–1984.
Zaichkowsky, L., Zaichkowsky, L., & Martinek, J. (1980). Growth
and development: The child and physical activity. St. Louis, MO:
C. V. Mosby.
402 P. Ford et al.
Downloaded By: [Lloyd, Rhodri] At: 11:20 21 January 2011