Chapter 6 Armstrong N, McManus AM (eds): The Elite Young Athlete. Med Sport Sci. Basel, Karger, 2011, vol 56, pp 97–105
Overtraining and Elite Young Athletes Richard Winsley ⭈ Nuno Matos Children’s Health and Exercise Research Centre, University of Exeter, Exeter, UK
Abstract In comparison to adults, our knowledge of the overtraining syndrome in elite young athletes is lacking. The evidence indicates an incidence rate of ~20–30%, with a relatively higher occurrence seen in individual sport athletes, females and those competing at the highest representative levels. The most commonly reported symptoms are similar to those observed in overtrained adult athletes: increased perception of effort during exercise, frequent upper respiratory tract infections, muscle soreness, sleep disturbances, loss of appetite, mood disturbances, shortness of temper, decreased interest in training and competition, decreased self-confidence, inability to concentrate. The association between training load and overtraining is unclear, and underlines the importance of taking a holistic approach when trying to treat or prevent overtraining in the young athlete so that both training and non-training stressors are considered. Of particular relevance to the issue of overtraining in the elite young athlete are the development of a unidimensional identity, the lack of autonomy, disempowerment, perfectionist traits, conditional love, and unrealistic expectations. Overtraining syndrome is a complex phenomenon with unique and multiple antecedents for each individual; therefore, an open-minded and comprehensive perspective is needed to successfully treat/prevent this in the young athlete. Copyright © 2011 S. Karger AG, Basel
Nearly a century ago, Hill [1] wrote that muscle soreness, stiffness, nervous exhaustion, metabolic disturbances and sleeplessness were all seen
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in the chronically fatigued athlete, all symptoms that have since become associated with overtraining. Since this time much research has focused on the overtrained athlete, but due to the complexity of this phenomenon, the detection, management and prevention of overtraining remains a real challenge. A common misperception is that overtraining (OT) is simply an issue about excessive training loads. In support of this viewpoint, the evidence shows that in the quest for improved performance, training loads have increased in parallel. For example, the Olympic swimmer Mark Spitz, winner of 7 gold medals in the 1972 Olympics, trained by swimming around 9 km per day, but within 20 years the average college swimmer had exceeded this training load [2] and a number of Olympic sports have reported a 20% increase in training loads in recent years [3]. Thus, for those who are, or strive to become, an elite athlete, this comes with the expectation that it will be achieved, often in a dose-response manner, by doing even more training; yet this has led some athletes to train so much that they have ended up overtrained [4]. If the young athlete finds themselves embroiled in a ‘more is better’ culture, propagated by the coaches, athletes and family that surround them, this may ultimately prove destructive and impair the
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Recovered
FOR
NFOR
OT
BO
Fig. 1. Overtraining continuum.
potential athlete’s chances of becoming an elite performer. Current understanding of OT is largely based on adult data and experience, with relatively little known about this condition in the young elite athlete. However, the available evidence suggests that OT is an issue for young athletes and an awareness of its multi-dimensional nature, will, it is hoped, mean that elite selection will be based on merit and not attrition.
What Is Overtraining?
What exactly is OT and how is it defined? Unfortunately, no agreed single definition of OT exists, something which in its own right has hampered understanding the phenomenon, and a number of alternative definitions are used. This lexicon of definitions has arisen because OT is not a single entity but, as some argue, rather a continuum of related and progressive conditions [5– 7] (fig. 1). Overtraining and overreaching (OR) arise when there is an imbalance between training fatigue and/or non-training stressors and recovery. More specifically, OR is an accumulation of training and non-training stressors that result in a short-term decrement in performance taking from days to several weeks to recover, whilst OT is an accumulation of training and non-training stressors that have detrimental long-term effects on performance and a recovery period that may
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take several weeks to months [6]. These definitions imply that the difference between OR and OT is seen in the duration of the performance loss and in the amount of time needed to recover and restore performance, but not in the type or duration of the stressors [8].
Overreaching and Overtraining
Athletes deliberately overload their bodies with physical training so that in the following recovery period, supercompensatory adaptations arise resulting in enhanced physical condition and performance [9]. Indeed, the sensitive management of the balance between overload and recovery on micro to macro scales underpins the science and practice of periodisation, thus many coaches argue that OR is a natural part of the training and supercompensation process. Functional overreaching (FOR) describes the period after an intense overload has been experienced, in which the athlete will be fatigued and there is a short-term decrement in performance, but after a few days or weeks, that recovery is complete and performance/fitness is enhanced. In contrast non-functional overreaching (NFOR) is characterized by stagnation or decrease of performance and a recovery period that lasts weeks to months [6]. If the NFOR becomes severe or protracted, there is the risk of the athlete progressing into a state of OT [6]. Although the position statement of the European College of Sports Sciences [6] provided
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needed clarity over the issue of OR, it failed to give guidance over the duration of each stage. This has made it difficult to distinguish the stage which the athlete is in and also, when does FOR become NFOR or ultimately OT [10]?
Overtraining Syndrome
It is important to note that the definition of overtraining has varied depending on the author or researcher, and that it can be used to describe a process, an outcome or both. Overtraining can be viewed as the process by which sport and nonsport specific stressors combine to negatively affect the athlete, but it can also be considered an outcome because of the long-lasting decrement in performance, mood disturbances, fatigue and /or depression [8]. In light of the wide range of physiological, psychological symptoms and performance decrements reported by the affected athletes, this condition is increasingly being defined as the OT syndrome [11, 12].
Burnout
Burnout and OT syndrome are terms often used interchangeably as both share many similarities. Foremost, they share diagnostic characteristics such as performance loss, mood disturbances and chronic exhaustion [13, 14]. Whereas OT research has traditionally investigated the maladaptive responses to excessive training [15], burnout research has focused primarily on psychosocial factors such as high external pressure, lack of control and feelings of entrapment [16, 17]. However, researchers do acknowledge that non-training stressors are important factors when studying the OT phenomenon [12] and that OT may be an antecedent to burnout [7] which makes the boundaries between these two phenomena blurred. Burnout denotes a negative emotional reaction to sport participation, and while it is known
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that overtrained athletes can still maintain their motivation to keep training, a burned-out athlete will commonly have no motivation to pursue his/her activity [14]. Repeated episodes of OT appear to increase the risk of burnout, with the motivation to continue training being the essential factor to differentiate between the seriousness of the OT episode and the likelihood of dropout [18]. In contrast to the progressive model of OT presented in figure 1, Richardson et al. [12] eloquently argue that burnout should not be seen as the end stage of the OT continuum but as a parallel condition arising from different antecedents; OT syndrome being the state of physical exhaustion arising from a prolonged imbalance between sports-related stressors and recovery, but burnout when the resulting exhaustion is primarily due to emotional factors. Other definitions used include staleness – initial failure of the body to cope with the psychological and physiological demands of training [7] – and unexplained underperformance syndrome (UPS) [19]. In an attempt to simplify the definition and criteria for the diagnosis of OT, Budget et al. [19] tried to reduce all the discordant OT terms into a single umbrella term – UPS – arguing that the term OT infers that causative factors exist, which often can be difficult to prove. Recently, Kellman [20] has focused more on the recovery aspects of athletes’ training, arguing that the main cause of overtraining is the lack of recovery between practice sessions. Under Kellman’s definition, to be overtrained is to experience underrecovery. The problem with this concept is that it ignores training loads as a potential causative factor and with its focus on physical recovery this disregards psychological recovery. Although there is no consensus about the terminology and definitions of the condition, what is clear is that this is a complex phenomenon with multiple presenting characteristics and stages. As with any condition with a continuum of seriousness, it is important to identify athletes who are at the beginning of this process (NFOR) from those
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who are at more advanced stages (OT), as recovery is suggested to be quicker if dealt with when the athlete is NFOR [6].
What Is the Incidence of the Overtraining Syndrome in Young Athletes?
Little is known about the incidence of NFOR or OT in young athletes and many questions remain unanswered: How common is it? At what age can it start? Are there differences in prevalence between different sports, between team and individual type sports, between the sexes? Is it a problem restricted to elite performers or is it evident at lower representative levels? Even in adults there are few empirical data of prevalence rates. The studies that have been performed frequently used few participants, often case studies, have employed different definitions of OT, making generalisations difficult. With these caveats in mind, the incidence of OT in elite long-distance runners has been reported at 60% and 64% in females and males, respectively [21]. The rate dropped to 33% in non-elite women runners, a difference attributed to the greater training distance performed by the elite runners [22]. In Collegiate athletes, the yearly incidence of overtraining averaged 10% in wrestlers [22] and 7– 31% in swimmers [11, 23]. Twenty-eight percent of US Olympic athletes reported being OT in the 90 days prior to the Atlanta games [24]. One of the largest surveys of adolescent athletes was performed by Raglin et al. [18] who assessed 231 young swimmers (14.8 ± 1.4 years) across four different countries (Japan, USA, Sweden and Greece), finding that 35% reported staleness at least once. Earlier data [25] showed that 31% of adolescent distance runners reported being overtrained but with the average episode lasting about 3 weeks, suggesting that the young athletes were actually NFOR rather than OT. Kentta et al. [5] investigated the prevalence of staleness in elite Swedish athletes (16–20 years) finding that 37%
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of the athletes had reported staleness at least once in their sport careers and that the incidence was greater in individual sports (48%) compared to team sports (30%). The prevalence of burnout (assessed using the Eades Burnout Inventory) in elite young Swedish athletes (n = 980, 17.5 ± 1.0 years), across 29 different sports was investigated by Gustafsson et al. [26]. Their findings indicated that 11% of individual sport and 5% of team sport athletes reported the highest levels of burnout scores in regard to negative self-concept of athletic ability; devaluation by coach and teammates; psychological withdrawal/devaluation and emotional/physical exhaustion. A recent survey of 376 English young athletes, mean age 15.1 ± 2.0 years (range 11–18 years) [Winsley and Matos, unpubl. data], indicated that 29% had been either NFOR or OT at least once in their sporting careers. There was a higher prevalence in individual sports than in team sports (37 vs. 17%) and in females than males (36 vs. 26%). This study intentionally surveyed young athletes from international down to club standard and although a higher incidence was seen in international (45%) and national (37%) level athletes, approximately 20% of subnational level young athletes also reported being NFOR/OT, suggesting that this is not just an issue specific to the elite child athlete.
What Are the Signs and Symptoms of Overtraining Syndrome in Young Athletes?
Although underperformance is regarded as the main characteristic of an OT athlete, it is not clear how much performance has to drop to confidently indicate a state of OT. To complicate things further, performance decrements can be the result of either OT or other precipitating factors such as family problems, school work, or exams [11, 12]. As a consequence much research has been conducted with the intention of trying to identify valid markers of OT, which could be used as both a diagnostic tool and as an early warning mechanism.
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Herein though lies the problem. Fry et al.’s [13] review listed more than 90 different symptoms that are reported by overtrained athletes spanning performance, physiological and psychological factors. Recent reviews by Urhausen and Kindermann [27] and Richardson et al. [12] reiterate the multitude of presenting symptoms but acknowledge that due to the large inter-individual variability of the symptoms themselves, just how difficult it is to diagnose an individual athlete with OT; which paradoxically is the whole point. The evidence suggests that the signs and symptoms reported in young athletes are similar to the ones found in the adult population. The commonly identified symptoms include increased perception of effort during exercise, frequent upper respiratory tract infections (URTI), muscle soreness, sleep disturbances, feelings of muscular heaviness, loss of appetite and mood disturbances [3, 5, 18]. Additional symptoms reported by young athletes during OT episodes are: increased conflicts with family, partner, coach or friends; decreased interest in training and competition; increased frustration with training; decreased self-confidence; inability to concentrate on a particular task; short temper, depression, sadness, and elevated levels of perceived stress [28]. Clearly, the individual nature of the symptomatology makes profiling a suspected overtrained young athlete difficult.
make themselves familiar with these possible risk factors –, it would be better to concentrate on those that might be particularly important for young elite athletes.
Is Training Load the Principal Cause of Overtraining in Young Athletes?
The importance of training load in the aetiology of OT has been endorsed by many authors [8, 29] and numerous adult studies have used increments in training load as the main variable to induce a state of OT/NFOR [30–32]; but this narrow view of the condition may mean that alternative contributors are not investigated and that interventions are focused on mistaken factors. The degree to which training load is a precursor for OT in young athletes remains unclear. Raglin et al. [18] reported that ‘stale’ swimmers aged 13–18 years had a training load 10.8% higher than ‘healthy’ swimmers; however, other studies have reported no relationship between the prevalence of burnout and training load [26]. Clearly, for some OT young athletes, an excessive training load and inadequate rest is indeed the principal reason underlying why they are overtrained, but it would be amiss to think that training load is the only reason for every case of OT and therefore alternative factors/stressors should also be considered [5, 12, 33].
What Are the Risk Factors of Overtraining Syndrome in Young Athletes?
Single Identity
Richardson et al. [12] provide an excellent summary of the proposed risk factors which range from training issues, situational and environmental stressors, people issues, athletes’ physical condition, athletes’ beliefs and attitudes, all of which may conspire to push the athlete into a state of OT. Rather than exhaustively repeat that which has been written on the topic in adults – although those involved with elite young athletes should
Coakley [16] argued that the time and training demands of the elite young athlete means that they have little or no opportunity to develop a normal, multifaceted identity – as such they become defined by their sport and their sport defines them. Young overtrained or burned out athletes frequently report that sport is the most important thing in their lives and that the amount of time that these individuals dedicate to other activities
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outside their sport is limited – suggesting the development of a unidimensional identity [16, 34]. Kentta et al. [5], for example, found that 20% of the young overtrained athletes in their study devoted less than 5 h a week to activities outside their sport, and for approximately 40% of these athletes, sport was the only thing (schooling and family aside) in their lives. Identities are claimed and constructed through social relationships experienced throughout life [35], therefore if sport/ training provides the sole opportunity for social interaction, it is unsurprising that the young athlete may develop a single identity. Self esteem, identity and self-worth become intertwined and become dependent on sporting success. This is fine when success is forthcoming, but can lead to stress and anxiety when failure/injury are present, possibly contributing to the development of OT. Furthermore, because of their unidimensional identity and lack of alternative avenues in life, some young athletes report that despite having negative experiences and low motivation they continue in their sport, in a scenario referred to as entrapment [36]. The development of self-complexity and multiple identities has been shown to provide a cushion or outlet for the stress related to training and appears to dampen the swings in selfbelief/doubt arising from their sport performance – resulting in a more balanced and better coping young athlete [16]. As such, those working with elite young athletes should help provide the opportunities and time for the development of a multi-dimensional identity in the athletes in their care.
Conditional Love, Meeting Expectations and Misperceptions
Wishing to meet parents/coaches expectations, and the anxiety this creates has been frequently mentioned by young athletes as an aggravating factor for OT. The child wishes to meet adults’
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expectations through showing their dedication to training and in the achievement of sporting success. If they fail to meet the standards that they perceive are expected of them this can result in increased training, feelings of guilt and threatened self-esteem – all contributory factors for OT or burnout. Additionally, if a ‘more-is better’ culture pervades the young athlete’s training environment, it may also result in a destructive conditional association; if the child gets or perceives to get more praise, acknowledgement, and love by training more and more. This drives the young athlete to keep training excessively, which can ultimately put them at risk of OT [12]. Likewise, there may be pressure to carry on training/competing even whilst tired or injured, combined with the fear of admitting to being so [37], which may push young athletes to continue despite physical/emotional risks. These forces become internalized and start to be manifested through the young person’s identity traits. Of course it is difficult to say whether the athlete’s personality is simply a reflection of the parental, sporting and societal influences to which they have been exposed or whether these are innate traits, but certain characteristics seem to be common within OT athletes. A perfectionist tendency in particular is frequently reported in burnt-out young athletes [38] which leads to the belief that more training/practice is required to achieve or sustain perfection and a greater level of self-admonishment if they are not meeting these performance ideals. It must be remembered that the coaches/parents are not always the villains, as conditional love can be a misperception by the child; the adults supporting and loving the child unconditionally irrespective of what they achieve in their sport. Finally, many young athletes are acutely aware of the sacrifices and commitment their parents/ coaches are making for them and do not want to let them down [16]. Thus, misunderstanding and misplaced guilt act to further reinforce the pressure on the child to train.
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Lack of Autonomy
A common pattern in the narratives described by adult athletes who experienced OT or burnout as a young elite athlete is the following: the young athlete shows talent/aptitude in a particular sport and achieves early success; the opportunity to become an elite young athlete presents itself and the child agrees; from this point forward the young athlete’s life is controlled by adults (coach/parents) in a effort to achieve these goals. Although this is often done with the best intentions and well meaning, the control that the adults assume for managing the young athlete’s training programme, competition schedules, travel plans, diet, free time, school work load, disempowers the child leaving them frustrated, impotent and stressed [12, 16]. In a recent study of 96 junior elite athletes, reduced self-determination was observed in those suffering from burnout [39]. These young athletes reported greater external regulation over their lives, were more extrinsically motivated, and consequently felt they had less self-determination over their actions, causing them stress and anxiety. Reduced autonomy and perceptions of powerlessness are directly related to the unidimensionality issue discussed previously, but are also expressed through control over the minutiae of the young athlete’s life by adults. Coakley [16] entitled it psychodoping, whereby the young athlete is made dependent on others and discouraged from asking critical questions about why they are participating, what they are doing and how their sporting existence is tied into the rest of their lives. The disenfranchisement of the young athlete even pervades the ‘treatment/ cure’ for OT; the child is assumed not to be coping and therefore is given coping strategies to help [17], but the real issue lies with a lack of selfdetermination and powerlessness over their lives and not in being able to cope with a system that is enforced on to them. Ensuring that young athletes are involved in the decision-making processes affecting their lives, on both a micro and macro
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scale, is important [37] and opportunities for this dialogue to occur should be given.
Prevention and Recovery
Because OT is a multidimensional entity any treatment/recovery strategies also need to take a holistic approach [12, 40]. This holistic style will shape not just the questions that are asked but also an appreciation of the interconnectivity of the issues. For example, if competition overload is identified as a concern, on a superficial level by simply cutting down the number of matches/events should resolve the problem as the child gets more rest. But it is important to go deeper and consider whether the young athlete is ever involved in the decision-making process in setting the competition schedule? What is the impact on their school workload and can they cope with this disruption? Has the schedule denied opportunities for socialization outside of the sport and thus potentially fostered the development of a single identity? Firstly, the adults and the young athlete must reflect and try to identify potential causes, whether training or non-training related. There must also be the maturity and openness by all to accept that they may be the source of the problem, and be willing to change accordingly. Asking such fundamental questions can be difficult both for adults and young athletes, but if these issues go unresolved because of denial and/or power inequities, then any recovery/prevention plan will be a façade and not deal with the root cause of the problem. In no particular order and by no means exhaustive, the following suggestions may help a coach to start to build a rounded profile of the young athlete, and address the issues pertinent to OT: • Meet the parents – ask about their motivations for helping the child, their opinion toward sport, their aspirations for the child, their own sporting experiences, how involved do they wish to be? Then ask the young athlete and then ask yourself the same questions.
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• Children with a sporting aptitude are in demand to play for their school, club, region, etc., so find out about the total training/competition schedule from all of these partners and what the weekly, monthly, yearly picture entails. • Be on the look out for frequent URTIs, complaints of sleeplessness, mood swings, weight loss and prolonged fatigue. • Ask the young athlete about interests outside of sport – what they do, who they meet, when they do this? • Ask the young athlete about the support network of family and friends. • Be alert for obsessive behaviours, perfectionist traits and the possibility of covert extra training. • Carefully plan the training schedule so that the training load is appropriate and that there is sufficient rest on a micro, meso and macro scale. • Is the young athlete given a regular opportunity to voice their opinions, do they have a say in the decisions made about their lives, are these listened to and considered fairly? • Ask about school and college workload – are they coping with the time management challenge this represents? • Ask about how supported the young athlete feels regarding the standard of coaching they are receiving, if there are financial pressures, how they feel about access to medical and sports science support services. Is this a source of frustration and anxiety?
Conclusions
The decision to aspire to become an elite athlete is often made by the child themselves, and this declaration of consent is taken as the justification for the subsequent time, effort and financial input by the adults involved, but is the child’s decision truly an autonomous one? With the lure of lucrative sponsorship deals, professional accolades, fame and reflected glory this can prove seductive for both the child and parents/coaches alike, meaning that there can be implicit pressure to make the choice to strive to become an athlete, even when the odds are stacked against them. As Brenner [41] points out ‘Most young athletes and their parents fail to realize that, depending on the sport, only 0.2–0.5% of high school athletes ever make it to the professional level’ [p. 1244] but even against this backdrop many set out to achieve this dream. On this journey it is clear that a significant minority (~20–30%) may become overreached, overtrained or burnt out [5, 18]. This represents many hundreds if not thousands of children, who are being let down by the care they are getting from the adults who are supposed to be responsible for them. We need to avoid the narrow view that the cause, treatment and prevention of OT can be reduced to a single physiological, psychological or sociological factor and instead look for an integral approach to this syndrome [40]. Elite selection after all, should be based on merit and not attrition.
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Dr. Richard Winsley Children’s Health and Exercise Research Centre School of Sport and Health Sciences, University of Exeter Exeter EX1 2LU (UK) Tel. +44 1392264724, Fax +44 1392264726, E-Mail
[email protected]
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