Can the ability to adapt to exercise be considered a talent—and if so, can we test for it?
Pickering and Kiely Sports Medicine - Open
Can the ability to adapt to exercise be considered a talent-and if so, can we test for it?
Craig Pickering 0 1
John Kiely 1
0 Exercise and Nutritional Genomics Research Centre, DNAFit Ltd , London , UK
1 Institute of Coaching and Performance, School of Sport and Wellbeing, University of Central Lancashire , Preston , UK
Talent identification (TI) is a popular and hugely important topic within sports performance, with an ever-increasing amount of resources dedicated to unveiling the next sporting star. However, at present, most TI processes appear to select high-performing individuals at the present point in time, as opposed to identifying those individuals with the greatest capacity to improve. This represents a potential inefficiency within the TI process, reducing its effectiveness. In this article, we discuss whether the ability to adapt favorably, and with a large magnitude, to physical training can be considered a talent, testing it against proposed criteria. We also discuss whether, if such an ability can be considered a talent, being able to test for it as part of the TI process would be advantageous. Given that such a capacity is partially heritable, driven by genetic variation between individuals that mediate the adaptive response, we also explore whether the information gained from genetic profiling can be used to identify those with the greatest capacity to improve. Although there are some ethical hurdles which must be considered, the use of genetic information to identify those individuals with the greatest capacity appears to hold promise and may improve both the efficiency and effectiveness of contemporary TI programmes.
1. Talent identification programmes often identify
those with the greatest current ability, as opposed to
the greatest capacity to improve.
2. This capacity to improve is linked to physical
adaptation to exercise, which is partially genetically
3. Genetic profiling holds promise in being able to
identify those individuals with the greatest capacity
to improve, as well as the best methods through
which to yield these improvements.
The accurate identification of youth sporting talent has, in
recent decades, emerged as a hugely important and yet
controversial topic [
]. Interest in talent identification
(TI) is illustrated by a growing academic literature [
along with a number of best-selling popular-science books
on the topic [
]. Traditionally, sporting TI programmes
have, through a mix of subjective and objective tests,
sought to identify young athletes with “talent,” using this
identification as a prediction of adult performance.
However, despite the massive allocation of resources into the
identification and development of young talent, it remains
unclear whether or not early TI processes are either
empirically justified or practically effective.
One fundamental limiting factor is that physical
performance tests employed to discern between those who
have the talent to excel in the future, and those who do
not, actually only provide a snapshot of current abilities.
The subsequent logical leap is the presumption that those
who perform well at that given time are most likely to be
successful as adults. Yet, due to the inherently non-linear
complex nature of biological maturation, these
performance snapshots offer inherently poor predictive value. As
an illustration, within athletes competing in the 2012
Olympic 100 m final, personal bests at age 18 ranged from
10.27–10.48 s. In comparison, one of this paper’s authors
(CP) ran 10.22 s at this age, faster than all the finalists.
Yet, whilst these athletes progressed to achieve multiple
sub-10s 100 m times, CP peaked at 10.14 s.
The reasons why CP, along with countless other
highperforming juniors, did not maintain their relative world
standings are obviously complex, varied and multifactorial
]. This illustrates the gross inaccuracies associated
with current approaches to predicting future senior
potential based on youthful performance. Similarly, where TI
processes have been empirically evaluated, these
inefficiencies remain, with fewer than 2% of athletes identified
as having the potential to be elite within a school sports
programme winning senior international medals .
Despite these inefficiencies, however, clubs and
organizations invest exorbitant sums on TI and development
initiatives in the hope of unearthing future talent.
Manchester City’s Academy programme, for example,
reportedly costs £12 million per year [
]. Yet such large
investment is perceived as both economically feasible and
justified by the occasional unearthing of exceptional talent;
15 Manchester City Academy graduates have been capped
at senior international level, and one, Shaun-Wright
Phillips, was sold by the club for £21 million.
A clear limitation of the TI process is that, during
maturation, current performance is not directly indicative of
future potential. In fact, no standard physical assessment
provides insight into how an individual is likely to
respond to future training. In this article, we explore the
possibility that the utilization of genetic markers
associated with the capacity to favorably respond to imposed
training stress may provide valuable, and currently
missing, insights relating to future trainability, rather than
current ability, thus providing clues as to whether the
athlete has the innate “talent” to respond to training.
The hereditary aspect of talent
A standardized, widely accepted definition of talent is hard
to find. A review of the complexities surrounding an
adequate definition of talent is beyond the scope of this
article; however, Issurin recently utilized a broad definition
of talent as “a special ability that allows someone to reach
excellence in some activity in a given domain” [
conceptualizing this definition, Issurin leaned heavily on
Howe and colleagues [
], who proposed that talent has
five properties: it is partially innate; its full effect may not
be evident at an early stage; it has early indications that
provide a basis for predicting who might excel; only a few
possess it; and it is domain specific.
Implicit within any definition of talent is the
assumption that it is at least partially genetically determined.
This is most obvious when considering the physiological
underpinnings of elite performance, all of which are, to
some degree, genetically influenced. Approximately 50%
of baseline maximal oxygen uptake (VO2max) is heritable
], as is 45–99.5% of muscle fibre type [
strength is estimated to be ~ 52% heritable .
Anthropometric qualities, often used as TI indicators, are
also genetically mediated, with height approximately
80% heritable [
]. So too are non-physical traits
associated with elite performance; for example, stress
resilience has a genetic component [
], as does
motivation to exercise . All of these findings suggest
that talent is at least partially mediated by genetic
factors. Indeed, de Moor et al. reported that 66% of the
variance in elite status is heritable [
Whilst elite athlete status appears to have a strong
genetic component, to date, it remains apparent that the
available genetic information is insufficient to reliably
predict those most likely to reach elite status in the
future. Gene variants (polymorphisms) most frequent in
elite athletes appear to hold little to no predictive ability
on their own. For example, a single nucleotide
polymorphism (SNP) in ACTN3, a gene encoding for a
protein found in fast-twitch muscle fibres, is associated with
elite sprint athlete status [
]. Here, between 97 and
100% of elite sprinters have at least one R allele, making
the XX genotype rare [
]. However, the fact that at
least some elite sprint and speed-power athletes have
the XX genotype [
] illustrates that it perhaps lacks the
sensitivity required to correctly identify talent. In
addition, approximately 82% of the world’s population
possess at least one R allele [
], thereby illustrating its
lack of discriminatory power in discerning between
potential athlete and non-athlete.
The inability of single SNP to effectively discriminate
between eventual phenotype has led to the suggestion
that utilizing a panel of SNPs, each associated with a
physical capacity deemed contributory to elite
performance, may provide greater predictive ability. Using such
an approach, a total genotype score (TGS) is calculated,
with a higher TGS indicative of a greater chance of
achieving elite status. This approach has had some
success, with mean TGS in athlete groups greater than
], although it does not yet appear to
distinguish between competitive levels within athlete
groups . Again, however, the sensitivity and specificity
are not sufficient to rule out false positives (identifying
someone as a future athlete who is later unsuccessful in
this endeavor) or false negatives (identifying someone as a
future non-athlete, who goes on to become a world-class
athlete). As such, the current consensus is that genetic
testing has no role to play in the TI process [
although this opinion is formed on the assumption that
elite athletes have common genotypes.
Is the ability to adapt to exercise a talent?
Whilst traditional TI programmes attempt to identify
future elite performers through the application of physical,
psychological and subjective evaluations, it is not clear
whether this is the best approach. One issue with the
use of such performance tests is that they measure the
current status of the athlete, as opposed to the potential
for that athlete to improve and develop. Consider the
use of a 60-m sprint test in order to identify talented
sprinters in a cohort of 15-year-olds. Whilst the test is
valid and will accurately identify the quickest athletes, it
is not clear that the fastest athletes at age 15 will be
fastest at age 25. There is, therefore, a mismatch between
what the test measures—current ability—and the TI
processes goal—identifying future ability [
]. Instead, the
focus of the TI process should be to find individuals with
the potential to develop their skills and physiology in
order to become successful senior athletes [
commonly referred to as talent development (TD).
TI programmes, therefore, should attempt to identify
those with the greatest ability to develop, provided that
their maximal ability is sufficient to be an elite athlete.
This fits into a model proposed by Tucker and Collins
], detailed in Fig. 1, whereby athletes have different
baseline abilities that reflect the untrained state, but also
different maximal abilities, which represent the
performance ceiling for each athlete. There is not necessarily a
relationship between the two; an athlete with a high start
point might have a low ceiling. Conversely, an athlete
with a low start point might have a higher ceiling. In this
model, what becomes key is the potential of the athlete
to improve with training—and whether they maximize
this potential. For exercise adaptation to be considered a
talent, it needs to fit the following five criteria proposed
by Howe and colleagues [
Is exercise adaptation partially innate?
An ever-increasing body of research now suggests that
genetic factors modify the adaptive response to exercise.
The seminal research in this regard is the HERITAGE
(Health, RIsk factors, exercise Training and GEnetics)
Family Study, in which sedentary adults undertook a 20-week
aerobic exercise training programme. The mean
postintervention improvement in VO2max in this cohort was
384 mL O2 min−1. However, some subjects saw no
improvement, whilst others exhibited much larger
improvements than the mean, as high as 1100 mL O2 min−1 [
Genetic factors accounted for almost 50% of this
interindividual variation [
]. Genetic association studies also
show the modifying impact of single SNP on exercise
adaptation. For example, R allele carriers of ACTN3 appear to
show greater improvements in power following a strength
training intervention than X allele carriers [
]. It is
clear that exercise adaptation is partly genetically driven,
and is therefore innate.
Are the full effects of this talent not fully evident at an early age?
Growth, maturation and the physical development of
youth athletes are non-linear in nature [
and adolescents are physically less able than adult elite
athletes due to differences in muscle size, strength [
and energy system development [
], which may limit
the magnitude and type of adaptations that are possible
]. This was illustrated by Radnor et al. [
reported that maturation modified the adaptive response to
resistance and plyometric training in a group of adolescent
males. Based on these findings, it appears that knowledge
of the full ability of a person to be able to adapt to exercise
is likely not fully understood until maturation has
], fulfilling this talent criterion.
Are there early indications of this talent?
This is perhaps the most difficult question to answer as
part of these criteria. In part, this is due to a lack of
research examining the magnitude of exercise adaptation in
youths, and comparing that to either the magnitude of
adaptation in those same youths as adults, or associating
that adaptive response with sporting success later in life.
There are responders and non-responders to specific
training interventions in youths [
], but it is not clear
how this affects adaptation in adulthood. Nevertheless,
the ability to adapt favorably to exercise as a youth will
positively impact development by taking the athlete from
their baseline towards their performance ceiling,
increasing the possibility of adult success.
Do only a minority of people possess this talent?
Overwhelmingly, research suggests that almost everyone
has the ability to adapt to exercise, with the small
number whom show no improvements labelled as
]. However, emerging research suggests
such exercise non-response abates with modification of
training parameters, such as an increase in training
] or frequency [
]. However, the magnitude
of training response differs between individuals. As
detailed earlier, this was apparent in HERITAGE, with a
mean post-training VO2max improvement of 19%,
although some subjects exhibited improvements of less
than 5%, and others improvements of > 40% [
wide-ranging magnitudes of adaptation have been
reported after strength training and combined strength
and endurance training [
]. It appears that, whilst
almost everyone exhibits positive adaptations to exercise,
those of the greatest magnitude are limited to a smaller
number of individuals, a hallmark of a talent.
Is this talent domain specific?
Whilst genetic variation exhibits a modifying effect on
exercise adaptation, the final point to consider is
whether this is global (i.e. all types of exercise) or
modality specific (i.e. individuals exhibiting large resistance
training adaptations do not necessarily exhibit the same
adaptive magnitudes to aerobic training). As previously
discussed, the ACTN3 R allele is associated with greater
improvements in muscle phenotype following resistance
]. However, regarding VO2max adaptation,
the X allele appears to be associated with larger
improvements , illustrating that the genetic
predisposition to exhibit a greater adaptive response is domain
specific. Karavirta et al. [
] randomized subjects to
receive strength training only, endurance training only,
concurrent strength and endurance training or no
training. Within each group, subjects exhibited the expected
range of adaptation; however, in the concurrent training
group, no subject was in the highest quintile of
improvement for both VO2peak and maximal voluntary
contraction, again indicating that an ability to respond
aerobically is separate to the ability to respond to
strength training. It appears, therefore, that the ability to
adapt favorably to exercise is specific to particular
domains, as opposed to a global ability.
Can we consider exercise adaptation a talent?
Exercise adaptation is a highly complex and
individualized process, mediated by genetic, environmental and
epigenetic factors [
]. The influence of variation at the
genetic level accounting for large amounts of the
interindividual adaptive response to exercise is clear [
], allowing the conclusion that the magnitude of
adaptation is partially innate. It is also domain specific, with
those possessing the ability to exhibit large
improvements following one type of training not guaranteed to
exhibit improvements of the same magnitude following
a different modality [
]. The presence of a small number
of individuals who have very large post-training
improvements in a physical trait [
] illustrates that only a few
possess this ability. The ability to exhibit large adaptations
to exercise is also potentially masked by maturation
effects. So far, there is a paucity of evidence examining
whether those athletes who are highly adaptable during
their youth remain so during their adult years.
Nevertheless, based on the evidence available, it does appear that
the ability to respond favorably, and with a large
magnitude, to exercise can be considered a talent.
Can we test for this talent?
Traditional TI processes appear to identify athletes who
are already more able than their peer group, as opposed
to those who represent the greatest ability to improve.
The ability to test for this latter trait would therefore
enhance the TI process, providing some predictive measure
as to the future level of the athlete. As Abbott and
] state, successful prediction of future
accomplishments requires identification of characteristics indicating
that an individual has the potential to both develop in
sport and become a successful senior athlete. Crucially,
recent research suggests that individuals respond optimally
to different types of training [
44, 54, 55
], illustrating that
being able to match promising youngsters with the
training type most likely to elicit the greatest improvements
could be invaluable. This can reduce the trial-and-error
process, increasing the time period available for an athlete
to maximize their potential by minimizing ineffective and
inefficient training methods.
Since the ability to respond to exercise is partially
mediated by genetic factors, being able to test for these factors
holds promise. Given that the impact of any one SNP on
this process is likely to be small, a more promising
approach is the use of whole genome or large (> 600,000)
SNP sequencing. A small number of studies have used this
process, with early evidence suggesting they could have
some predictive ability [
]. This process is separate
from the use of genetic testing to identify the commonly
held definition of sporting talent—adult
performance—whereby promising athletes’ genetic profiles are compared
to a pool of elite athletes to look for commonalities, the
assumption being that a greater number of commonalities
is associated with a greater chance of being elite. At
present, there is no evidence to support this . Indeed,
it is likely that different genes impact baseline ability (what
is commonly identified in traditional TI processes) and
ability to adapt to exercise, as detailed in Fig. 1. Certainly,
a greater body of research is required before
evidencebased guidelines for the use of genetic testing to support
talent development (as opposed to pure TI) can be
utilized, but these early findings hold promise. Given the
issues discussed within the current TI process, it could be
argued that anything that improves the current offering
should be utilized.
In addition, there are a host of ethical questions that
surround genetic testing, not just within sports, but also
public health [
]. For example, is it acceptable to test
under 18s, who may not have the required maturity to
both fully understand the results in context and give
informed consent? What happens if, as part of a routine
genetic test, a disease-associated SNP is discovered? To
avoid this, should such gene variants be removed from
the testing panels? Can clubs insist that their contracted
players must undertake a genetic test, and who owns
that data when the test is completed? The resolution of
such considerations is a challenge to the translation of
laboratory-based genetic research to the field, but they
are related to how the information is presented and
interpreted, as opposed to whether genetic information
should or should not be used.
Whilst widespread across sport, traditional TI processes
have a number of inherent problems. Perhaps the
biggest issue is that they appear to identify current ability,
as opposed to future potential, a fact which is not helped
by the poor predictive ability of currently used tests of
talent. Instead, TI programmes might be better placed to
identify youngsters with the greatest capacity to improve,
which is partially comprised of the ability to adapt to
exercise. As genetic factors account for approximately 50%
of the variation in adaptation to exercise, profiling to
uncover these genetic underpinnings could be a useful
future adjunct to the TI process, and also allow for
athletes to undertake training that they are more likely
to see favorable adaptations to, creating a personalized
training process making athletes more likely to achieve
their potential. With the many inefficiencies and high
costs associated with TI, it is clear that we only need to
be marginally better at the TI process in order to be
disproportionately more effective at developing talent, and
genetic testing potentially represents this marginal gain.
Within this paper, we have focused on the physiological
aspects of talent and talent identification. It is, however,
worth noting that sporting prowess is not depending
solely on physiology, and a number of psycho-emotional
and cognitive traits are also associated with athletic
achievement. Such traits include, for example, innate
stress resilience, and a host of attitudinal factors, such as
motivation, perseverance and personality dispositions [
]. Importantly, as with other phenotypes, these
capacities are also partially mediated by hereditary
influences and partly by life history [
]. In summary, the
ability to positively respond to the training stimuli
imposed by physical exercise fulfils the required criteria to
be considered a talent. The emergence of genetic testing
may enable the more accurate identification of athletes
who, thanks to a favorable genetic profile, possess a
heightened ability to exhibit the greatest responses to
training, thus improving the efficiency and efficacy of
the talent identification process.
Availability of data and materials
CP conceived the idea underpinning this manuscript and prepared the first
draft. JK provided critical feedback as to the manuscript’s content and
structure and contributed to the writing of the later drafts and final
submitted version of the manuscript. Both authors have read and approved
the final manuscript.
No sources of funding were used to assist in the process of writing this
CP is an employee of DNAFit Ltd., a genetic testing company, and is
undertaking a Professional Doctorate in Elite Performance at the University
of Central Lancashire (UK). His research interest is understanding the
potential utility of genetic information in elite sport. JK is a Senior Lecture in
Elite Performance at the Institute of Coaching & Performance at the
University of Central Lancashire.
Ethics approval and consent to participate
Consent for publication
Craig Pickering is an employee of DNAFit Ltd. He received no financial
incentive for the production of this manuscript which was produced as part
of his Professional Doctorate studies. John Kiely has no interests to declare.
Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations.
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