ArticleLiterature Review

Overtraining in Elite Athletes

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Abstract

Overtraining is an imbalance between training and recovery. Short term overtraining or ‘over-reaching’ is reversible within days to weeks. Fatigue accompanied by a number of physical and psychological symptoms in the athlete is an indication of ‘stateness’ or ‘overtraining syndrome’. Staleness is a dysfunction of the neuroendocrine system, localised at hypothalamic level. Staleness may occur when physical and emotional stress exceeds the individual coping capacity. However, the precise mechanism has yet to be established. Clinically the syndrome can be divided into the sympathetic and parasympathetic types, based upon the predominance of sympathetic or parasympathetic activity, respectively. The syndrome and its clinical manifestation can be explained as a stress response. At present, no sensitive and specific tests are available to prevent or diagnose overtraining. The diagnosis is based on the medical history and the clinical presentation. Complete recovery may take weeks to months.

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... Consequently, athletes and coaches are continually challenged to find the optimal balance between training and recovery to enhance athletic performance. A disruption in this balance may result in impaired performance [3,4]. ...
... During a typical training cycle, athletes often undergo periods of overload and recovery in an attempt to optimise physical performance. The process of overload is achieved through an increase in training load [3]. Acute fatigue occurs following overload training which may result in a ...
... temporary performance decrement [5]. When adequate rest is prescribed, the resultant acute fatigue may be followed by a positive adaptation or improvement in performance [3]. This process is referred to as functional overreaching (FOR). ...
Article
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Purpose: To provide details on the nature and symptomatic profile of training maladaptation in competitive resistance-based athletes to examine whether there are symptoms that may be used as prognostic indicators of overtraining. Identifying prognostic tools to assess for training maladaptation is essential for avoiding severe overtraining conditions. Methods: A Web-based survey was distributed to a cross-sectional convenience sample of competitive athletes involved in sports with a significant resistance-training component. The 46-item anonymous survey was distributed via industry experts and social media from July to August 2019. Results: The final sample included 605 responses (completion rate: 84%). About 71% of the respondents indicated that they had previously experienced an unexplained decrease in performance. Among those, the majority reported a performance decrement lasting 1 wk to 1 mo (43.8%). General feelings of fatigue were the most frequent self-reported symptom of maladaptation. Acute training maladaptation, lasting <1 mo, was also accompanied by symptoms of musculoskeletal aches and pain. In the majority of cases (92.5%), training maladaptation was accompanied by additional nontraining stressors. A greater proportion of the respondents with more severe maladaptation (>4 mo) were training to muscle failure. Conclusion: The results from this study support the multifactorial nature of training maladaptation. The multidimensional nature of fatigue and individual variability in symptomatic responses precludes definitive prognostic symptoms or differential diagnostic factors of functional/nonfunctional overreaching or the overtraining syndrome in resistance exercise.
... The theoretical basis for their inclusion is due to the potential influence of various training-induced physiological processes that originate in central (i.e., 'central command') and peripheral (e.g., afferent feedback from skeletal muscles) body regions to alter cardiac ANS function (i.e., the balance between the sympathetic and parasympathetic systems), and subsequently HR activity [10,38,42]. It has been hypothesized that training-induced fatigue or an incomplete recovery might result in a greater muscle activation at a given intensity [129], promoting increased oxygen demands [129] and yielding accelerated cardiac sympathetic activity that consequently increase HRex, and reduce HRR and HRV [114,129]. In contrast, previous research has proposed that increased training stress (leading at least to an overreaching state) may cause opposite responses -increased parasympathetic activity or blood plasma volume, consequently lowering HRex and increasing HRR and HRV [37,38,130]. ...
... The theoretical basis for their inclusion is due to the potential influence of various training-induced physiological processes that originate in central (i.e., 'central command') and peripheral (e.g., afferent feedback from skeletal muscles) body regions to alter cardiac ANS function (i.e., the balance between the sympathetic and parasympathetic systems), and subsequently HR activity [10,38,42]. It has been hypothesized that training-induced fatigue or an incomplete recovery might result in a greater muscle activation at a given intensity [129], promoting increased oxygen demands [129] and yielding accelerated cardiac sympathetic activity that consequently increase HRex, and reduce HRR and HRV [114,129]. In contrast, previous research has proposed that increased training stress (leading at least to an overreaching state) may cause opposite responses -increased parasympathetic activity or blood plasma volume, consequently lowering HRex and increasing HRR and HRV [37,38,130]. ...
... The theoretical basis for their inclusion is due to the potential influence of various training-induced physiological processes that originate in central (i.e., 'central command') and peripheral (e.g., afferent feedback from skeletal muscles) body regions to alter cardiac ANS function (i.e., the balance between the sympathetic and parasympathetic systems), and subsequently HR activity [10,38,42]. It has been hypothesized that training-induced fatigue or an incomplete recovery might result in a greater muscle activation at a given intensity [129], promoting increased oxygen demands [129] and yielding accelerated cardiac sympathetic activity that consequently increase HRex, and reduce HRR and HRV [114,129]. In contrast, previous research has proposed that increased training stress (leading at least to an overreaching state) may cause opposite responses -increased parasympathetic activity or blood plasma volume, consequently lowering HRex and increasing HRR and HRV [37,38,130]. ...
Preprint
Team-sports staff often administer non-exhaustive exercise assessments with a view to evaluating current physiological state or fitness–fatigue status, to inform decision-making on athlete management (e.g., future training or recovery). Submaximal Fitness Tests (SMFT) have become prominent in team-sports settings for observing responses to a standardised physical stimulus, likely due to their time-efficient nature, relative ease of administration and physiological rationale. It is evident, however, that many variations of SMFT characteristics, response measures and monitoring purposes exist. The aim of this review is to provide a theoretical framework of SMFT and a detailed summary of their use as indicators of fitness–fatigue status in team-sports. Using a systematic review of the literature, we identified five distinct SMFT protocols characterised in their combinations of exercise regimen (continuous or intermittent) and the progression of exercise intensity (fixed, incremental or variable). Heart rate (HR) derived indices were the most studied outcome measures in SMFT and included exercise (HR exercise) and recovery (HR recovery and vagal-related HR variability) responses. Despite the disparity between studies, these measures appear more relevant to detect positive changes in fitness (i.e., maximal oxygen uptake, intermittent endurance capacity), whereas their role in detecting fatigue associated with variations in ANS function is not yet clear. Psycho-physiological outcome measures such as ratings of perceived exertion were less common SMFT outcome measures in team-sports, but their potential utility when collected alongside objective measures (e.g., HR exercise) has been advocated. Mechanical outcome measures included Global-Positioning-System-derived locomotor variables—such as distance covered, primarily during standardised training drills (e.g., small-sided games) to monitor exercise performance (i.e., fitness status)—or response measures derived from inertial-measurement units to monitor lower limb neuromuscular function and subsequently fatigue status. Whilst there is an emerging interest regarding the utility of these mechanical measures, their measurement properties and underpinning mechanisms are yet to be fully established. Further, it is essential to better understand the methodological aspects of SMFT characteristics in relation to all outcome measures. Herein, we provide a deeper synthesis of the available literature, culminating with best-evidence practical recommendations and directions for future research.
... In pursuit of performance excellence, the desired positive physiological adaptations are best achieved when the total workload, variations in activities, and intensity of exercise are appropriate and progressively introduced (i.e., considering fitness, prior training, health history, age, and hereditary potential), while complemented with regular and sufficient restorative rest. In contrast, a training regimen that is excessive, unduly straining, and without recurrent adequate recovery may provoke a range of maladaptations, resulting in stagnant or worsening exercise performance, undesirable mood/ behavioral changes, and a greater risk of injury and/or illness (Kuipers and Keizer, 1988;Kraemer and Ratamess, 2005;Meeusen et al., 2013;Cadegiani and Kater, 2019a). This chronic, dysfunctional, maladapted state has been given various names (e.g., staleness, underperformance syndrome, under-recovery) since it was first recognized. ...
... To clarify its nature, investigators attempted to define OTS and theoretically distinguished it from overreaching (Figure 1), beginning in the mid-1980s (Kuipers and Keizer, 1988;Morgan et al., 1988;Fleck and Kraemer, 1982). OTS accordingly was defined as an accumulation of training and/or non-training stress and consequent strain which results in longterm athletic performance decrements that require several weeks or months to resolve. ...
... Thus, not surprisingly, no consistent biomarker or reliable laboratory test related to the above or other metrics has been identified and validated. The fact remains that 1) OTS is extremely difficult to elicit in controlled studies (Fry and Kraemer, 1997;Kraemer et al., 1998), 2) participants may not have reached a true state of OTS during experimental observations, despite intense and extensive physical training (Häkkinen et al., 1989;Meeusen et al., 2013), and 3) the clinical features of OTS differ from one individual to the next, usually are nonspecific, and may be anecdotal (Kuipers and Keizer, 1988;Morgan et al., 1988;Uusitalo et al., 1998;Eichner, 1995). ...
Article
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The phenomenon of reduced athletic performance following sustained, intense training (Overtraining Syndrome, and OTS) was first recognized more than 90 years ago. Although hundreds of scientific publications have focused on OTS, a definitive diagnosis, reliable biomarkers, and effective treatments remain unknown. The present review considers existing models of OTS, acknowledges the individualized and sport-specific nature of signs/symptoms, describes potential interacting predisposing factors, and proposes that OTS will be most effectively characterized and evaluated via the underlying complex biological systems. Complex systems in nature are not aptly characterized or successfully analyzed using the classic scientific method (i.e., simplifying complex problems into single variables in a search for cause-and-effect) because they result from myriad (often non-linear) concomitant interactions of multiple determinants. Thus, this review 1) proposes that OTS be viewed from the perspectives of complex systems and network physiology, 2) advocates for and recommends that techniques such as trans-omic analyses and machine learning be widely employed, and 3) proposes evidence-based areas for future OTS investigations, including concomitant multi-domain analyses incorporating brain neural networks, dysfunction of hypothalamic-pituitary-adrenal responses to training stress, the intestinal microbiota, immune factors, and low energy availability. Such an inclusive and modern approach will measurably help in prevention and management of OTS.
... Consequently, athletes and coaches are continually challenged to find the optimal balance between training and recovery to enhance athletic performance. A disruption in this balance may result in impaired performance [3,4]. ...
... During a typical training cycle, athletes often undergo periods of overload and recovery in an attempt to optimise physical performance. The process of overload is achieved through an increase in training load [3]. Acute fatigue occurs following overload training which may result in a ...
... temporary performance decrement [5]. When adequate rest is prescribed, the resultant acute fatigue may be followed by a positive adaptation or improvement in performance [3]. This process is referred to as functional overreaching (FOR). ...
Article
Full-text available
Background The balance between training stress and recovery is important for inducing adaptations to improve athletic performance. However, continuously high training loads with insufficient recovery may cause fatigue to accumulate and result in overtraining. A comprehensive systematic review is required to collate overtraining literature and improve the current understanding of the mechanisms underlying functional overreaching (FOR), non-functional overreaching (NFOR) and the overtraining syndrome (OTS) in resistance training. Objective The objective of this systematic review was to establish markers of overtraining and elucidate the mechanisms underlying maladaptive resistance training conditions. Furthermore, this review aims to critically evaluate the methodological approaches of the overtraining literature. Methods A systematic literature search was performed on PubMed, Web of Science and SPORTDiscus to identify studies up to June 2019. Electronic databases were searched using terms related to resistance training and overtraining. Records were included if they attempted to induce a state of overreaching or overtraining through resistance exercise in healthy participants. Results A total of 22 studies were selected for review. Among these studies, eight resulted in decrements in performance and measured changes in performance during a follow-up period. There were four studies that reported decrease in performance yet failed to implement follow-up measures. A total of 10 studies reported no decline in performance. Overall, a lack of standardisation in methodology (follow-up performance testing) and diagnostic criteria prevents consistent determination of FOR, NFOR and OTS in resistance training. Conclusions Few studies have appropriately established FOR, NFOR or OTS in resistance training. Overtraining may be related to frequent high-intensity and monotonous resistance training. However, no marker other than a sustained decrease in performance has been established as a reliable indicator of overtraining in resistance exercise. Registration This systematic review was registered on the Open Science Framework (https://osf.io/) ( https://doi.org/10.17605/osf.io/5bmsp).
... Mesocycles consisting of multiple training blocks following this principle while not providing ample time for recovery can often lead athletes to develop exhaustion in one or more physiological systems (18). The development of both non-functional overreaching (NFOR) and overtraining syndrome are consequences from prolonged stress and eventual exhaustion due to an imbalance between recovery, training stress, environment stress, or emotional and psychological stress (261,269). ...
... Previous literature suggests that overtraining or NFOR can promote hormonal imbalances in an athlete (154,261). These alterations in hormones can lead to autonomic imbalances seen through fluctuations in HRV (269,398,472). ...
... It is postulated to develop from an over stimulation of the sympathetic nervous system which in turn promotes a reduction in vagal related HRV indices (269). With prolonged sympathetic stimulation comes increased excitation and arousal due to the excess release of epinephrine and norepinephrine; this increased level of excitation stimulates a negative feedback response where a down regulation in the alpha and beta adrenoceptors diminishes sympathetic nervous system control whereby the autonomic nervous system then gravitates towards parasympathetic dominance (261,269). Such a theory gives rise to the idea of a bell-shaped response in HRV when progressing through the stages from overreaching to overtraining syndrome (261,269). ...
Thesis
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Background: The monitoring of an athlete’s training load and cardiac function have demonstrated to be valuable assessment tools in individual sporting events. Additionally, short term heat acclimation has shown to be effective for stimulating hypervolemia and augmenting cardiovascular performance. A gap in the literature exists indicating further research is required into both heat acclimation protocols and the monitoring of on-field training load and its cause and effect relationship with heart rate variability in team sport. Purpose: The purpose of this investigation was twofold; 1) identify a novel form of heat acclimation using hot yoga for augmenting cardiovascular and aerobic performance, and 2) identify an effective monitoring protocol suitable for team sport using internal training load and heart rate variability. Methods: The Canadian Women’s National Field Hockey team were participants for examining heat acclimation and the relationship between training load and autonomic modulation during the 2016 Olympic cycle. A maximal graded exercise test was completed prior to and following six hot yoga sessions to examine cardiovascular and aerobic performance measures. Results: In Chapter 4, six days of hot yoga developed hypovolemia that lead to trivial improvements in aerobic power, run time to exhaustion, and a small increase in running speed at each ventilatory threshold. A non-existent relationship between markers of exercise stress and alterations in plasma volume during and post hot yoga were observed. Chapter 5 identified a large relationship between the planned and achieved on field training load over a complete mesocycle. Additionally, a moderate relationship was observed between both time spent above anaerobic threshold, training load and alterations in the Ln rMSSD:R-R ratio.
... That it was not could be indicative of overtraining or functional overreaching. Overtraining in humans is where an athlete is unable to perform at their optimal level after a normal rest period, due to training load, and is therefore associated with a decrease in performance (Kuipers and Keizer, 1988). Overtraining in horses is based on the measurement of reduced performance capacity and has been defined as a decrease (p<0.05) in run time to fatigue during an incremental exercise test on a high-speed treadmill, and a significant decrease in bodyweight (with no reduction in feed intake) (Tyler, Golland et al., 1996). ...
... Overtraining in horses is based on the measurement of reduced performance capacity and has been defined as a decrease (p<0.05) in run time to fatigue during an incremental exercise test on a high-speed treadmill, and a significant decrease in bodyweight (with no reduction in feed intake) (Tyler, Golland et al., 1996). In contrast, functional overreaching is defined as a short-term reduction in performance as a result of increased training stress and is reversible over a few days with a lightened training load, or a brief period of no training (Kuipers and Keizer, 1988;Bayly, 2002). It is important to note that in humans, adaptations and maladaptations to training load are observed in blood biomarkers before behavioural modification, prior to any negative impact on performance (Arent, 2018). ...
Thesis
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Mild equine asthma (MEA) is an inflammatory airway disease of the horse which affects a large proportion of the equine population. The pathogenesis of MEA is not fully elucidated, however, it is widely assumed to be a multifactorial disease, with expression of clinical signs largely influenced by environment. There is very little information available on the effects of treatment, which is typically focused on reducing airway inflammation through corticosteroid administration. Investigations into the equine respiratory environment in states of health and MEA were performed using: i) High-throughput sequencing techniques (16S and ITS2) to report the respiratory microbiota and mycobiota respectively, and ii) changes in relative inflammatory mRNA cytokine expression in bronchoalveolar lavage fluid (BALF). Changes in expression of inflammatory cytokine mRNA, equine herpesvirus (EHV)-1,2,4,5 glycoprotein B gene expression and changes in respiratory bacterial and fungal communities following dexamethasone treatment of healthy horses and those with MEA are explored. A portable equine ergospirometry system was used to determine the efficacy of treatment designed to reduce lung inflammation on aerobic (V ̇O2peak) and anaerobic performance in horses with MEA. There were clear differences between the lower respiratory tract environment in healthy horses versus MEA. There was a clear separation in both the microbiota-Streptococcus was increased in horses with MEA-and relative inflammatory cytokine expression. Horses with MEA had a lower concentration of
... In these domains, researchers examined these processes under the terms psychological or physical resilience and load (or stress) and recovery (e.g. Brink et al., 2010;Bryan et al., 2019;Galli & Gonzalez, 2015;Gijzel et al., 2019;Hill et al., 2018a;Kenttä & Hassmén, 1998;Kuipers & Keizer, 1988;Reilly & Ekblom, 2005;Varadhan et al., 2018;Whitson et al., 2016). ...
... In the disciplines of physiology and sports science, the themes of physical resilience and load and recovery are typically focused on the process of bouncing back following stressors (e.g. Brink et al., 2010;Gijzel et al., 2019;Kenttä & Hassmén, 1998;Kuipers & Keizer, 1988;Rector et al., 2021;Reilly & Ekblom, 2005;Varadhan et al., 2018;Whitson et al., 2016). That is, athletes need to recover when their biopsychosocial system is perturbed by physiological stressors. ...
Article
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Athletes are exposed to various psychological and physiological stressors, such as losing matches and high training loads. Understanding and improving the resilience of athletes is therefore crucial to prevent performance decrements and psychological or physical problems. In this review, resilience is conceptualized as a dynamic process of bouncing back to normal functioning following stressors. This process has been of wide interest in psychology, but also in the physiology and sports science literature (e.g. load and recovery). To improve our understanding of the process of resilience, we argue for a collaborative synthesis of knowledge from the domains of psychology, physiology, sports science, and data science. Accordingly, we propose a multidisciplinary, dynamic, and personalized research agenda on resilience. We explain how new technologies and data science applications are important future trends (1) to detect warning signals for resilience losses in (combinations of) psychological and physiological changes, and (2) to provide athletes and their coaches with personalized feedback about athletes’ resilience.
... The overreaching phase of the peaking protocol is the period of time where the main training stimulus is applied. During this period, there are increases in training load and intensity resulting in an acute performance decrease and commensurate fatigue increase [6]. Overtraining often occurs when the training load frequency is too great or the body is not given the resources (e.g. ...
... Overtraining often occurs when the training load frequency is too great or the body is not given the resources (e.g. time, nutrients) to recover [6]. Overtraining can be attributed to a decrease in performance, motivation, immune system function, and/or injury [7]. ...
Article
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Powerlifting competition is comprised of three barbell lifts: squat, bench press, and deadlift that are all completed in a single day and summed together, ultimately normalized to the lifter’s body weight via the Wilks Coefficient. This figure is then subsequently employed to determine the “best” athlete in that meet. During the competition preparation, powerlifters often undergo peaking protocols which include physiologically taxing overreach and low-volume, recovery-focused taper phases to collectively induce super-compensatory strength adaptations. Heart rate variability (HRV) has emerged as an easily accessible, user-friendly biomarker for autonomic nervous system-associated fatigue and readiness. Therefore, the purpose of this observational study was to investigate the potential impact of a peaking protocol on fatigue/readiness via HRV measurements and its possible relationship with competitive powerlifting performance. Daily measurements of HRV were taken, each morning, using the HRV4Trainning smartphone application by nineteen competitive powerlifters (26.16±4.56 years) from 14-days prior to a peaking protocol, throughout individual peaking phases, on meet day, and 14- days following competition. A quadratic regression was used to determine the predictability of HRV measurements and powerlifting performance. The change in HRV from competition day to baseline was found to be a significant predictor of Wilks coefficient (p=0.038, R2=0.336; mean±SE log- transformed root mean square of successive R-R intervals [lnRMSSD] = -51.98±22.23). Although extrapolations of the present study are limited by inherent subject peaking protocol variability, these data suggest HRV may nonetheless represent a viable means to modulate individual athlete training programs to promote recovery.
... Table 6 displays some of the signs, symptoms and health consequences of athletes diagnosed as having the Overtraining Syndrome. The syndrome results in a chronic under-performance, negative health consequences (see Table 6), and typically can end or curtail an athlete's competitive season (56,57,77). The development of the Overtraining Syndrome has been reported in a multitude of sports, regardless of the emphasis on training modality employed (e.g., runners vs. weight lifters vs. tennis players) although the specific symptoms and frequency of select symptoms can be somewhat sports specific (74,75). ...
... In the case of the second proposed mechanism, several researchers' decades ago demonstrated short-and long-term caloric deficient results in testosterone reductions in men (92)(93)(94). It is well-recognized that a common finding is overtrained athletics is weight loss and suppressed appetite/anorexic tendencies (56,61). The effect of inadequate caloric intake on testosterone seems more related to central HPG axis suppression than direct action at the testes as both LH and FSH levels ...
Article
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For decades researchers have reported men who engaged in intensive exercise training can develop low resting testosterone levels, alterations in their hypothalamic-pituitary-gonadal (HPG) axis, and display hypogonadism. Recently there is renewed interest in this topic since the International Olympic Committee (IOC) Medical Commission coined the term "Relative Energy Deficiency in Sports" (RED-S) as clinical terminology to address both the female-male occurrences of reproductive system health disruptions associated with exercise. This IOC Commission action attempted to move beyond the sex-specific terminology of the "Female Athlete Triad" (Triad) and heighten awareness/realization that some athletic men do have reproductive related physiologic disturbances such as lowered sex hormone levels, HPG regulatory axis alterations, and low bone mineral density similar to Triad women. There are elements in the development and symptomology of exercise-related male hypogonadism that mirror closely that of women experiencing the Triad/RED-S, but evidence also exists that dissimilarities exist between the sexes on this issue. Our research group postulates that the inconsistency and differences in the male findings in relation to women with Triad/RED-S are not just due to sex dimorphism, but that there are varying forms of exercise-related reproductive disruptions existing in athletic men resulting in them displaying a relative hypogonadism condition. Specifically, such conditions in men may derive acutely and be associated with low energy availability (Triad/RED-S) or excessive training load (overtraining) and appear transient in nature, and resolve with appropriate clinical interventions. However, manifestations of a more chronic based hypogonadism that persists on a more permanent basis (years) exist and is termed the "Exercise Hypogonadal Male Condition." This article presents an up-to-date overview of the various types of acute and chronic relative hypogonadism found in athletic, exercising men and proposes mechanistic models of how these various forms of exercise relative hypogonadism develop.
... These concepts have been distinguished by (Morton, Ferry, & Keast, 1991 and R. Kuipers, H.;Keizer, H. A., 1988). They affirm that the overtraining characterized by a state of fatigue, has an intensive drive to the point that is observed, a recovery period to regain its potential to work, and by a decrease in performance. ...
... These concepts have been distinguished by (Morton, Ferry, & Keast, 1991 and R. Kuipers, H.;Keizer, H. A., 1988). They affirm that the overtraining characterized by a state of fatigue, has an intensive drive to the point that is observed, a recovery period to regain its potential to work, and by a decrease in performance. ...
... These concepts have been distinguished by (Morton, Ferry, & Keast, 1991 and R. Kuipers, H.;Keizer, H. A., 1988). They affirm that the overtraining characterized by a state of fatigue, has an intensive drive to the point that is observed, a recovery period to regain its potential to work, and by a decrease in performance. ...
... These concepts have been distinguished by (Morton, Ferry, & Keast, 1991 and R. Kuipers, H.;Keizer, H. A., 1988). They affirm that the overtraining characterized by a state of fatigue, has an intensive drive to the point that is observed, a recovery period to regain its potential to work, and by a decrease in performance. ...
Article
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Abstract: Introduction: The main objective of this study is to detect the existence of a state of fatigue and a syndrome of overtraining among Algerians judokas of the youngest category (girls and boys) by the use of the questionnaire of fatigue among the child athlete (QFES) and to evaluate the variations of the score by report has its 07 dimensions. Method: 24 judokas cadets of the national team, 14 boys 58.3% and 10 girls 41,7%. The boys are an average age of 16.21±0.21 years, an average weight of 67±16,40kg and a stature of 171,64±9,49cm. They have a body mass index(BMI) of 22.69±4.94 kg/m².girls have an average age of 16.20±0.78 years, a weight of 59.1±7.89 kg and a stature of 163.9±3,14cm.The BMI is equal to 21,95±2.50 kg/sq. m. The athletes are attending school between the fourth average year at the College and the second year of secondary school. During the period of the microcycle stage of competition which is taking place between 01 March 2017 and 31 May 2017, we distributed the questionnaire at the end of the competition at the Championship in Algeria (Algiers, 27/05/2017). Results: The score of the questionnaire was to 40.01±8.58 (minimum=27, 00, maximum=54), 33.33% of athletes their scores to the QFES≥45. The average score for an item is 1.1±0.11. The ranking of items of the QFES by average quotation with significant threshold retained of p<0.05. The results are expressed in average ± standard deviation. Conclusion: The main results show that in the questionnaire QFES fatigue is a sensitive tool to detect a state of fatigue. However, a biological study is imperative in order to establish the correlation between syndrome of the overtraining and oxidative stress among young judokas
... Sampling from saliva is very popular because it is non-invasive [3]. Researchers have shown that salivary composition changes in response to stress [4][5][6][7][8] and had a strong association with their serum concentrations [9][10][11]. In response to physical activity [12], such as during competitions [1,13], the activities of the Hypothalamic Pituitary Adrenal (HPA) and the Sympathetic Adrenal Medullary (SAM) axes increase to maintain homeostasis [14,15]. ...
... In addition, significant association between the salivary sAA protein and training outcomes was suggested to underline its potential as non-invasive marker of training status in professional athletes [16]. Activation of the HPA axis results in secretion of cortisol, which increases in response to competitive stress [1,2,8]. ...
Article
Objectives The purpose of the present study was to investigate the effect of competition on stress salivary biomarkers alpha-amylase (sAA), cortisol, and dehydroepiandrosterone (DHEA) in elite or amateur female adolescent inline skaters. Material and methods Eighteen female adolescent inline skaters (9 elites and 9 amateurs) who have competed in official skate competitions, participated in the present study. Unstimulated whole saliva was collected during their rest day, 1 h and immediately before competition (pre-competition), as well as immediately and 1 h after the competition (post-competition). Free cortisol, sAA, DHEA, and total protein concentrations were assessed. Results Cortisol concentrations of elite group significantly increased 1 h before and pre-competition compared to rest day (P < 0.05) whereas no significant changes observed in amateur group (P > 0.05). The sAA concentrations were significantly higher in the elite group at 1 h before and at pre-competition compared to the rest day (P < 0.05). sAA concentrations of amateur group were significantly higher at pre-competition, post-competition, and 1 h after competition compared to the rest day (P < 0.05). DHEA levels of both groups markedly decreased 1 h after competition compared to the rest day (P < 0.05). No significant differences in DHEA concentrations were observed between the two groups (P > 0.05). The ratio of DHEA to cortisol exhibited significant difference among the five measurement stages in the amateur group (P < 0.05), whereas no significant changes in this ratio were observed in the elite group (P > 0.05). The total protein concentrations of the elite group increased significantly during three stages, pre-competition, post-competition, and 1 h after competition compared to rest day (P < 0.05). Additionally, the total protein concentrations at pre-competition and 1 h after competition were significantly higher in elite group (P < 0.05). Conclusion Our results confirmed that the optimum increase in adrenal activity occurs before a competition, which can improve athletic performance. However, a similar increase after a competition suggests the body's attempt to maintain homeostasis. Therefore, anticipatory stress indicates that athletes need to relax before a competition.
... This amount is referred to as 1 metabolic equivalent (also 1 MET). Maximum oxygen consumption VO 2max is the highest rate of oxygen transport and utilization achieved during exertion at maximum physical load (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). ...
... Certain types of trainings, such as interval, acceleration, and sprints, trigger the anaerobic processes. Consequently, these are very exhausting for the athlete and must be planned carefully in order to avoid exhaustion, resulting in an undesired effect, i.e., over-training [12][13][14][15]. ...
Chapter
The process of sports training consists of four phases: planning, realization, control and evaluation. In the planning phase, trainers prescribe a training load that must be overcome by the athlete during the realization. The response of the athlete on the load represents physical stress. This can be measured indirectly by several physical measures, of which heart rate is the most useful. The realization phase of sports training is controlled by sports trainers using appropriate measuring tools. On the basis of performance analysis, the realized sessions are evaluated, typically at the end of the training cycle. This evaluation influences the adaptation of future training process.
... For instance, it was shown that sCort is more pronounced in home as compared to away competitions [13], when there is more audience [1], or when competing as a couple as compared to a larger group [78]. While this acute increase in stress system activity is useful and has often been associated with better athletic performance [52,57], prolonged training periods and repeated competitions are assumed to result in a constant wear and tear of the athlete's body and negative health consequences [6,53]. ...
Article
Objective: Due to the impact of stress and related psychophysiological responses on competitive performance, psychological interventions that reduce stress and may thus increase athletic performance need to be evaluated. In this pilot study, the effects of a mindfulness-based intervention (MBI) on competitive anxiety, self-confidence and mindfulness, and autonomic and endocrine stress responses to a competition in elite athletes were explored. Methods: Twenty-six male elite Wushu athletes (N = 26) were randomly assigned to either MBI (8 weeks) or a wait-list control group. Both groups participated in three competitions at baseline, immediately post intervention, and at a 2-month follow-up. Athletes completed the Competitive State Anxiety Inventory-2 prior to the competitions. Saliva, from which the stress markers cortisol (sCort) and alpha-amylase (sAA) were determined, was collected prior to and after competitions as well as after awakening and in the evening of competition days. Results: Repeated measures ANOVAs showed that the MBI group, but not the wait-list control group, demonstrated an increase in self-confidence and mindfulness and a decrease in competitive anxiety from baseline to post intervention (all p < .001, all ɳp2 > 0.39). The MBI group exhibited lower sCort daily levels (p = .001, ɳp2 = 0.332) and lower sCort (p = .013, ɳp2 = 0.121) and sAA responses (p = .022, ɳp2 = 0.119) to the competition after the intervention. Daily sAA was unaffected by the intervention (p = .742, ɳp2 = 0.011). These changes remained stable up to the 2-month follow-up. Conclusions: The present pilot study suggested that mindfulness-based intervention might be associated with a diminished physiological and psychological stress responses to competition. Whether this in turn translates to change in performance needs to be examined in future studies with larger samples. Moreover, different sport activities need to be considered before findings can be generalized.
... The term overreaching was first described as a period of short-term overtraining which sometimes results in a mild form of staleness [35]. The term was later defined as an accumulation of training and/or non-training stress resulting in a short-term decrement in performance capacity with or without related physiological and psychological signs and symptoms of overtraining in which restoration of performance capacity may take several days to several weeks [27]. ...
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There are variable responses to short-term periods of increased training load in endurance athletes, whereby some athletes improve without deleterious effects on performance, while others show diminished exercise performance for a period of days to months. The time course of the decrement in performance and subsequent restoration, or super compensation, has been used to distinguish between the different stages of the fitness–fatigue adaptive continuum termed functional overreaching (FOR), non-functional overreaching (NFOR) or overtraining syndrome. The short-term transient training-induced decrements in performance elicited by increases in training load (i.e. FOR) are thought be a sufficient and necessary component of a training program and are often deliberately induced in training to promote meaningful physiological adaptations and performance super-compensation. Despite the supposition that deliberately inducing FOR in athletes may be necessary to achieve performance super-compensation, FOR has been associated with various negative cardiovascular, hormonal and metabolic consequences. Furthermore, recent studies have demonstrated dampened training and performance adaptations in FOR athletes compared to non-overreached athletes who completed the same training program or the same relative increase in training load. However, this is not always the case and a number of studies have also demonstrated substantial performance super-compensation in athletes who were classified as being FOR. It is possible that there are a number of contextual factors that may influence the metabolic consequences associated with FOR and classifying this training-induced state of fatigue based purely on a decrement in performance may be an oversimplification. Here, the most recent research on FOR in endurance athletes will be critically evaluated to determine (1) if there is sufficient evidence to indicate that inducing a state of FOR is necessary and required to induce a performance super-compensation; (2) the metabolic consequences that are associated with FOR; (3) strategies that may prevent the negative consequences of overreaching.
... An increase in training intensity has the potential to have negative consequences if not done gradually. Over training can result in exhaustion and injury (Kuipers & Keizer, 1988). "You're fatigued [from] the lack of sleep, the lack of downtime, the […] two, three-hour training sessions twice a day" (Nicole). ...
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... Despite the benefits of weight-bearing activity for BMD, at the elite sporting level, too much activity to the point of overtraining can result in negative outcomes (Kuipers and Keizer 1988). A stress fracture would be one such outcome and is defined as a partial or complete fracture of bone from repeated application of force lower than that required to fracture a bone in a single loading (Iwamoto and Takeda 2003). ...
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Low bone mineral density (BMD) is established as a primary predictor of osteoporotic risk and can also have substantial implications for athlete health and injury risk in the elite sporting environment. BMD is a highly multi-factorial phenotype influenced by diet, hormonal characteristics and physical activity. The interrelationships between such factors, and a strong genetic component, suggested to be around 50–85% at various anatomical sites, determine skeletal health throughout life. Genome-wide association studies and case–control designs have revealed many loci associated with variation in BMD. However, a number of the candidate genes identified at these loci have no known associated biological function or have yet to be replicated in subsequent investigations. Furthermore, few investigations have considered gene–environment interactions—in particular, whether specific genes may be sensitive to mechanical loading from physical activity and the outcome of such an interaction for BMD and potential injury risk. Therefore, this review considers the importance of physical activity on BMD, genetic associations with BMD and how subsequent investigation requires consideration of the interaction between these determinants. Future research using well-defined independent cohorts such as elite athletes, who experience much greater mechanical stress than most, to study such phenotypes, can provide a greater understanding of these factors as well as the biological underpinnings of such a physiologically “extreme” population. Subsequently, modification of training, exercise or rehabilitation programmes based on genetic characteristics could have substantial implications in both the sporting and public health domains once the fundamental research has been conducted successfully.
... Career prevalence of close to two-thirds are described (Morgan et al. 1987;Morgan et al. 1988;Vogel et al. 2001). Evidence exists, that recovery from overreaching may take two to three weeks, however clear definitions are not reported (Vogel, 2001;Kuipers et al. 1988;Hooper & Mackinnon, 1995;Urhausen & Kindermann, 2002). From a pathophysiological mechanism, often a sympathetic and a parasympathetic overreaching respectively overtraining are reported (Vogel, 2001;Hooper & Mackinnon, 1995;Urhausen & Kindermann, 2002;Israel, 1958). ...
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Introduction. Maximum performance can only be achieved with an optimal balance of training and recovery. Already 15 years ago Jeukendrup & Hesselink (1994) mentioned that hints can be derived from lactate curves concerning a potential overreaching. In this small study we show the effects of a six-week standard infantry military training on performance capacity in young elite orienteers. The potentially induced overreaching and the ingoing alterations of heart rate patterns and lactate answers shall be analysed. Material & Methods. Five young elite orienteers (22.6 ± 0.52 years / 178.4 ± 7.6 cm / 66.4 ± 3.4 kg) completed an exhaustive treadmill test, first at one and a half year before, second at half a year before and third immediately after completing a six-week period of a session of a hard infantry military training. Results. After the six-week additional military training measurements of heart rate decreased at speed 10.8 km/h from 142.6 ± 11.6 to 129.2 ± 11.9 (p = .0192); at speed 12.6 km/h from 153.4 ± 11.4 to 141.2 ± 12.6 (p = .0192); at speed 14.4 km/h from 166.4 ± 10 to 155.4 ± 12.2 (p = .02); at speed 16.2 km/h from 177.4 ± 6.9 to 168.4 ± 6.5 (p = .0244); at speed 18 km/h from 186.2 ± 5.8 to 181.4 ± 3.6 (p = .0313) compared to the measurement half a year earlier. Discussion. We strongly believe that these lower average heart rates for submaximal speed stages cannot be assessed as positive in terms of performance but might be in accordance with a parasympathetic overreaching respectively parasympathetic stimulation. The increased parasympathetic tone probably required a correspondingly stronger sympathetic stimulus for activation, which, however, could not act as efficiently as after normal training conditions as athletes were not rested well yielding to a shift of the heart rate/performance curve in line with findings of Jeukendrup & Hesselink (1994) of lactate curve in cyclists already 15 years ago.
... 2 3 Therefore, an accurate assessment of training intensity is essential to achieve the desired results and avoid overtraining. 4 Exercise intensity is defined as the amount of metabolic energy required in the unit of time to perform a specific muscular work and can be monitored through variables which are closely correlated to energy expenditure, such as oxygen consumption (V O 2 ), power output, speed and heart rate. 5 In endurance performance, exercise intensity can easily be estimated using a percentage of maximum heart rate (% HRmax) or a percentage of heart rate reserve (% HRR). 1 6 These methods, based on the assumption of a linear relationship between heart rate and oxygen consumption, were validated in shortterm incremental exercises. ...
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Introduction The measurement of heart rate is commonly used to estimate exercise intensity. However, during endurance performance, the relationship between heart rate and oxygen consumption may be compromised by cardiovascular drift. This physiological phenomenon mainly consists of a time-dependent increase in heart rate and decrease in systolic volume and may lead to overestimate absolute exercise intensity in prediction models based on heart rate. Previous research has established that cardiovascular drift is correlated to the increase in core body temperature during prolonged exercise. Therefore, monitoring body temperature during exercise may allow to quantify the increase in heart rate attributable to cardiovascular drift and to improve the estimate of absolute exercise intensity. Monitoring core body temperature during exercise may be invasive or inappropriate, but the external auditory canal is an easily accessible alternative site for temperature measurement. Methods and analysis This study aims to assess the degree of correlation between trends in heart rate and in ear temperature during 120 min of steady-state cycling with intensity of 59% of heart rate reserve in a thermally neutral indoor environment. Ear temperature will be monitored both at the external auditory canal level with a contact probe and at the tympanic level with a professional infrared thermometer. Ethics and dissemination The study protocol was approved by an independent ethics committee. The results will be submitted for publication in academic journals and disseminated to stakeholders through summary documents and information meetings.
... There are studies in the literature showing both a significant decrease in VO 2 max in well-trained athletes who stopped training for 3-6 weeks [6,7] and a reduction in capillary density, oxidative capacity [5], mean cross-sectional area of muscle fibers [8], EMG activity, and changes in fiber type [9]. According to Kuipers and Keizer, the complete cessation of training in a well-trained, competitive athlete can result in a 2 of 11 syndrome of detraining, relaxation, exercise abstinence, or exercise addiction [10]. Such effects are noticed when training is suddenly interrupted due to injury or other unplanned circumstances. ...
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This study aims to evaluate the effects of a prolonged transition period (detraining) on the physical capacity, power, and speed parameters of elite swimmers. Fourteen swimmers (seven females and seven males) aged 20.4 ± 1.7 years participated in the study. The athletes were subjected to two rounds of identical tests at 12-week intervals during the detraining period (DP), which consisted of an evaluation of the athletes’ body weight and composition, a measurement of the power of their lower limbs (Keiser squat, countermovement jump (CMJ), akimbo countermovement jump (ACMJ)) and upper limbs (Keiser arms) on land, and 20-m swimming using the legs only (Crawl Legs test), arms only (Crawl Arms test), and full stroke (Front Crawl test). An analysis of variance revealed a significant effect of the main factor, Gender, on all the measured parameters, while for the factor Detraining, except for Front Crawl (W) (F = 4.27, p = 0.061), no significant interaction effect (Gender × Detraining) was revealed. Among both the male and the female participants, a reduction in lactate-threshold swimming speed (LT Dmax) and a reduction in swimming speed and power on the Crawl Arms, Crawl Legs, and Front Crawl tests was observed after 12 weeks. There were also statistically significant reductions in ACMJ and CMJ jump height and upper-limb power (Keiser squat) among the female and male swimmers. There were no significant changes in body weight or body composition. The study showed a clear deterioration in results for most of the parameters, both for those measured on land and for those measured in water.
Chapter
In the last chapter, the automatic generation of sports training plans using CI algorithms was presented, where it was expected that the their realization would be proceeded smoothly. However, realization of the proposed training plan can be disrupted when an athlete in training process ill or is injured. These unpredictable events can interrupt the training process for a day or two, or even for several weeks. In this case, the training plan becomes unusable and must be adapted.
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Le recours aux activités physiques et sportives en santé mentale est connu depuis longtemps. De nos jours, il prend toute son importance, en association des traitements médicamenteux et des psychothérapies. Ces pratiques, quand elles sont adaptées à l'état clinique ont un impact, vérifié par les méta-analyses mondiales, à la fois neurobiologique, cérébral, métabolique et physiologique. Elles sont bénéfiques pour les personnes porteuses de souffrance psychique épisodique (dépression de l'humeur) ou chronique (schizophrénie). L'effet psycho-social et relationnel suscité compte aussi pour beaucoup dans la prévention, l'amélioration des troubles et le rétablissement. Cet ouvrage pluridisciplinaire témoigne de pratiques innovantes. Avec Mauraine CARLIER, Yvonne DELEVOYE-TURRELL, Manuella DE LUCA, Lilian FAUTRELLE, Nathalie GODART, Robin MILESI, Souganya SAMY-BERTHOMIER, Djea SARAVANE, René TEMPIER.
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This chapter deals with identifying the characteristics of athletes in training. According to the theory of the sports training, this identification is conducted after an evaluation phase, where goals set prior to the training cycle are compared with the achieved results. The purpose of this process is to discover those characteristics of the athlete that have the greatest positive impact on performance. Improving these characteristics needs to be more strongly emphasized in the planning the training sessions in next training cycles.
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Chapter
This chapter presents an automatic construction of sports dietary plans based on the training plan generated by an artificial sports trainer. Differential evolution serves as the core algorithm for this purpose. The goal of this algorithm is to select the suitable foods from a food list dataset according to estimated macro-nutrient requirements. The main advantage of the algorithm is introduced by a domain-specific language for food description that allows a flexibility and autonomy in the construction of the dietary plans.
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The triple‐match principle, as outlined by the Demand‐Induced Strain Compensation (DISC) Model, states that resources are most effective when they match particular demands. The present study investigates the role of match in elite sport with regard to the relation between sport‐related demands, sport‐related resources, and vigor (i.e., physical strength, cognitive liveliness, and emotional energy). We hypothesized that moderating effects of resources on the relation between demands and vigor are most likely when there is a triple‐match between demands, resources and vigor, followed by double‐match and non‐match. A cross‐sectional survey study was conducted among 118 semi‐professional and professional athletes (70 females, 48 males, Mage = 24.7, SD = 6.5). Physical resources moderated (i.e., strengthened) the positive relation between physical demands and physical strength, whereas emotional resources moderated (i.e., buffered) the negative relation between emotional demands and emotional energy. Moderating effects of sport‐related resources on the relation between sport‐related demands and vigor occurred more often when there was a triple‐match compared to when there was less match or no match at all. These findings indicate that, also in the domain of elite sport, resources do not randomly moderate the relation between demands and well‐being. Implications and limitations of the study are discussed. This article is protected by copyright. All rights reserved.
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The aim of this study is to investigate whether the change in (sub)maximal heart rate after intensified training is associated with the change in performance. Thirty subjects were recruited who performed cardiopulmonary exercise tests to exhaustion 2 weeks before (pre), 1 week after (post) and 5 weeks after (follow-up) an 8-day non-competitive amateur cycling event (TFL). The exercise volume during the TFL was 7.7 fold the volume during the preparation period. Heart rate and cardiopulmonary parameters were obtained at standardised absolute submaximal workloads (low, medium and high intensity) and at peak level each test. Subjects were classified as functionally overreached (FOR) or acute fatigued (AF) based on the change in performance. No differences between FOR and AF were observed for heart rate (P = .51). On total group level (AF + FOR), post-TFL heart rate decreased significantly at low (−4.4 beats·min⁻¹, 95% CI [−8.7, −0.1]) and medium (−5.5 beats·min⁻¹ [−8.5, −2.4]), but not at high intensity. Peak heart rate decreased −3.4 beats·min⁻¹ [−6.1, −0.7]. O2pulse was on average 0.49 ml O2·beat⁻¹ [0.09, 0.89] higher at all intensities after intensified training. No changes in ⩒O2 (P = .44) or the ventilatory threshold (P = .21) were observed. Pearson’s correlation coefficients revealed negative associations between heart rate and O2pulse at low (r = −.56, P < .01) and medium intensity (r = −.54, P < .01), but not with ⩒O2 or any other submaximal parameter. (Sub)maximal heart rate decreased after the TFL. However, this decrease is unrelated to the change in performance. Therefore, heart rate seems inadequate to prescribe and monitor intensified training.
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Triathlon consists of swimming, cycling, and running. Due to the large volume of training required, athlete injury may be the result of mechanical or physiological insult. Overuse injuries are common, as are traumatic injuries. However, athletes may also suffer physiological injury as a result of overwhelming the homeostatic mechanisms of the body. Many injuries can be avoided through appropriate planning in both the short and long term, termed periodization.
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Key points: •Overload training is required for sustained performance gain in athletes (functional overreaching). However, excess overload may result in a catabolic state which causes performance decrements for weeks (non-functional overreaching) up to months (overtraining). •Blood ketone bodies can attenuate training- or fasting-induced catabolic events. Therefore, we investigated whether increasing blood ketone levels by oral ketone ester (KE) intake can protect against endurance training-induced overreaching. •We show for the first time that KE intake following exercise markedly blunts the development of physiological symptoms indicating overreaching, and at the same time significantly enhances endurance exercise performance. •We provide preliminary data to indicate that growth differentiation factor 15 (GDF15) may be a relevant hormonal marker to diagnose the development of overtraining. •Collectively, our data indicate that ketone ester intake is a potent nutritional strategy to prevent the development of non-functional overreaching and to stimulate endurance exercise performance. Abstract: It is well known that elevated blood ketones attenuate net muscle protein breakdown, as well as negate catabolic events, during energy deficit. Therefore, we hypothesized that oral ketones can blunt endurance training-induced overreaching. Fit male subjects participated in two daily training sessions (3 weeks, 6 days/week) while receiving either a ketone ester (KE, n = 9) or a control drink (CON, n = 9) following each session. Sustainable training load in week 3 as well as power output in the final 30 min of a 2-h standardized endurance session were 15% higher in KE than in CON (both P < 0.05). KE inhibited the training-induced increase in nocturnal adrenaline (P < 0.01) and noradrenaline (P < 0.01) excretion, as well as blunted the decrease in resting (CON: -6 ± 2 bpm; KE: +2 ± 3 bpm, P < 0.05), submaximal (CON: -15 ± 3 bpm; KE: -7 ± 2 bpm, P < 0.05) and maximal (CON: -17 ± 2 bpm; KE: -10 ± 2 bpm, P < 0.01) heart rate. Energy balance during the training period spontaneously turned negative in CON (-2135 kJ/day), but not in KE (+198 kJ/day). The training consistently increased growth differentiation factor 15 (GDF15), but ∼2-fold more in CON than in KE (P < 0.05). In addition, delta GDF15 correlated with the training-induced drop in maximal heart rate (r = 0.60, P < 0.001) and decrease in osteocalcin (r = 0.61, P < 0.01). Other measurements such as blood ACTH, cortisol, IL-6, leptin, ghrelin and lymphocyte count, and muscle glycogen content did not differentiate KE from CON. In conclusion, KE during strenuous endurance training attenuates the development of overreaching. We also identify GDF15 as a possible marker of overtraining.
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Purpose of the research is to make a comparative analysis of competitive exercise techniques in weightlifting based on the gender peculiarities. Materials and methods of the research. The research contains a comparative analysis of morphofunctional indicators of men and women, which influence the competitive exercise techniques. Results. The comparative analysis revealed differences in the competition techniques based on the gender peculiarities in morphofunctional indicators, load parameters for men and women engaged in weightlifting. Сonclusion. The revealed differences in competitive exercises techniques for men and women engaged in weightlifting will give the opportunity to develop optimal content of training process of weightlifters.
Chapter
For many people, sport is one of the stress-relieving activities. People being involved with sport wish to achieve attractive shape, healthy lifestyle, lose weight, and so on. However, there are also people who deal with sport because of competition goals. In order to fulfill their competition goals, they need to train properly. Even for professionals, it is very hard to perform a serious training. On the other hand, recent expansion of smart sport watches and even smart phones allow athletes to train smarter. During the months and years, they produce dozens of activity files. These files offer thousands of opportunities for data mining approaches, where athletes gained a deep insight into their training data. Data mining approaches are able to extract habits of athletes, help to prevent over-training syndrome and injuries, clustering similar activities together, and much more. In this chapter, the authors show opportunities for data mining, enumerate recent applications, and outline future potential for research and applications in the real world.
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Athletes typically train to enhance performance and achieve competition goals; however, too much exercise training with insufficient recovery can result in the athlete becoming overtrained. When the overtraining syndrome occurs, decrements in performance are the most prominent symptom, but others include fatigue, changes in mood state, competitive incompetence, and changes in sleep patterns, just to name a few. As the endocrine system is very involved in physiological adaptations and recovery to stress, it has received substantial attention in the overtraining literature. Ultimately, it appears that there is no single endocrine marker capable of identifying overtraining, and evidence to date suggests there probably never will be. Since the primary symptom of overtraining is a decrement in performance, regular monitoring is key to preventing its development through guiding the planning of training sessions to ensure sufficient recovery and consistent positive adaptations.
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Background: Taper is considered as a strategy to avoid overtraining and increase peak performance in athletes. Because aerobic exercise increases the level and duration of independence during the lifespan, the participation of recreational athletes has increased in running events around the world. However, the effects of using load reduction in their training and aerobic performance are still not well known. Objectives: Our goal was to compare load manipulations, using tapering-like periods in the end of recreational athletes training evaluating alterations in oxygen supply, muscle injury, and metabolism markers. Methods: Healthy males (n = 88, 20-35 years old) were randomly distributed in groups using a combination of two mesocycles of 4 weeks, undulatory and staggered, with two daily microcycles, undulatory and linear. Undulatory-undulatory (Und-Und) and undulatory-linear (Und-Lin) groups had load reduction in the final week of training while the staggered-undulatory (Sta-Und) and staggered-linear (Sta-Lin) groups did not. Cardiorespiratory capacity (V̇O2max), body mass index (BMI), and body fat % were evaluated. Blood samples were also collected to analyze hematocrit (Ht), mean corpuscular hemoglobin (MCHC), circulating levels of hemoglobin (Hb), creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea (U), cortisol (C), free testosterone (FT), and free T/C ratio. Results: After 8 weeks of training, Und-Und had the highest trend to increase V̇O2max. Both Und-Und and Sta-Lin reduced body fat %. Und-Und showed a significant increase in MCHC, T and Free T/C ratio, a positive trend to increase Ht% and Hb levels, and a trend to decrease CK, LDH, and C circulating levels. Sta-Lin presented a trend to decrease Ht% and Hb levels, a significant increase in CK, LDH, AST, ALT circulating levels, and a decrease in Free T/C ratio. Conclusion: The use of daily undulatory training load provides better gains for aerobic fitness while the use of staggered load, mainly associated with linear load, promotes inadequate recovery in recreational runners.
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A prospective, randomised study assessed the impact of high-intensity racetrack conditioning on aerobic and anaerobic capacities in seasoned Thoroughbred racehorses. The effect of 10 weeks race conditioning and two simulated races on V̇O 2max and maximum accumulated oxygen deficit (MAOD) were evaluated. An incremental treadmill test to determine V̇O 2max , followed by three supramaximal runs to fatigue (at speeds (V105%, V115%, V125%) corresponding to oxygen requirements 105%, 115% and 125% of V̇O 2max , in randomised order) were performed at each timepoint (T1 [pre-conditioning] and T2 [post-conditioning]). Prior to T1, racehorses were briefly de-trained for four-six weeks and given low-level treadmill conditioning to prepare them for the more strenuous race conditioning after T1. Paired variables between T1 and T2 were analysed using a paired t-test. A 2-way RM ANOVA compared variables with >1 measurement. Speed at V̇O 2max (P=0.04) and V̇O 2max (P=0.01) increased with conditioning. Calculated speeds for the supramaximal runs increased for V105% (P=0.02) and V115% (P=0.03) but not for V125% (P=0.08). There was no conditioning effect on time to fatigue (P=0.34), although it was different between all intensities (2.8, 2.2 and 1.4 mins at V105%, V115% and V125% respectively at T2). O 2 demand increased with conditioning (P=0.02) for each supramaximal intensity. On average, horses’ aerobic capacity improved 4.43% after conditioning. MAOD was unchanged with conditioning (P=0.25) and unaffected by exercise intensity. Fit racehorses that have undergone repeated intensive training programs, experience smaller, incremental improvement than completely unfit horses. The anaerobic capacity of previously trained racehorses is relatively stable, despite brief periods of de-training.
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In many elite sport performance contexts, overtraining is a critical issue for coaches to understand, recognise and respond to. While the indicators and effects of overtraining have attracted considerable research interest, there are no diagnostic tests that reliably predict impending overtraining. This study explores the practices and beliefs of three highly successful professional elite rowing coaches as they predict and manage the risk of athlete overtraining during crucial periods of intensive training. These coaches took part in a series of semi-structured interviews that explored their practices, philosophies and experiences. The research draws on sociological perspectives pertinent to coaching pedagogy and, more specifically, the tenets of naturalistic decision-making in exploring how the coaches define and make decisions about overtraining. In doing so it recognizes that coaching involves decision-making in complex and demanding situations. The coaches were found to monitor the fatigue of their rowers through observation, communication and measures of training pace. In general, the intuitions and cues that were used by coaches had little in common with overtraining markers or indicators that are promoted in the sport science literature. Coaches’ decision-making was based largely on subjective information and processes that were influenced by a range of stressors unique to their positions. We contend that the research provides an important new perspective on coaches’ definitions and management of overtraining and enables management of overtraining to be better understood as a key element of coaching pedagogy in elite performance settings. In this article we argue successful coaches have unique insights into this topical area and this is worthy of future exploration.
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It is widely agreed that overtraining should be employed in order to achieve peak performance but it is also recognised that overtraining can actually produce decrements in performance. The challenge appears to be one of monitoring stress indicators in the athlete in order to titrate the training stimulus and prevent the onset of staleness. The present paper summarises a ten-year research effort in which the mood states of competitive swimmers have been monitored at intervals ranging from 2-4 weeks during individual seasons for the period 1975-1986. The training cycle has always involved the indoor season which extends from September to March and the athletes who served as subjects were 200 female and 200 male competitive swimmers. The results indicate that mood state disturbances increased in a dose-response manner as the training stimulus increased and that these mood disturbances fell to baseline levels with reduction of the training load. Whilst these results have been obtained in a realistic setting devoid of experimental manipulation, it is apparent that monitoring of mood state provides a potential method of preventing staleness.
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THOMPSON, J. K. and P. BLANTON. Energy conservation and exercise dependence: a sympathetic arousal hypothesis. Med. Sci. Sports Exerc, Vol. 19, No. 2, pp. 91-99, 1987. The present article reviews a wide range of studies which suggest that energy balance mechanisms are affected by food restriction and exercise training. Specifically, food restriction produces adaptive decreases in basal metabolic rate, a decrease in the energy utilized in the performance of a specific task, and an increase in the efficiency of food utilization following resumption of pre-restriction feeding patterns. Exercise training produces an adaptive decrease in the energy required to perform a specific task and in the hormonal output to a standard work task. Conflicting evidence exists on the combined effects of exercise and dieting on energy conservation. This energy balance information is used as the basis for the development of a sympathetic arousal hypothesis of exercise dependence. We propose that exercise dependence is mediated by adaptive reductions in sympathetic output to exercise tasks as a result of training, requiring the individual to engage in heightened levels of activity to produce pre-training levels of physiological arousal. (C)1987The American College of Sports Medicine
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We measured RBC count, blood hemoglobin concentration, and related hematologic factors in 12 male marathon runners during a 20-day, 312-mile road race. The RBC and hemoglobin levels decreased significantly, from 5.17 million per cubic millimeter and 16.0 g/dL, respectively, to 4.36 million per cubic millimeter and 13.4 g/dL. Although the runners became marginally anemic during the race, their running speeds were not significantly changed. There were no abnormal clinical signs other than rare instances of hematuria. This study indicates that a sudden increase in long-distance running mileage above the regular training level may cause "sports anemia," a functional pseudoanemia that, in mild cases, does not impair endurance performance.(JAMA 1981;246:1215-1218)
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MYOCARDIAL infarction (MI) and sudden death are periodically reported in previously healthy young adults during strenuous exercise or athletic competition. The majority of these cases are explained by latent coronary atherosclerosis, anomalous coronary morphological conditions, or hypertrophic cardiomyopathy.1 However, exercise-related MI may also occur in young persons without apparent abnormalities of coronary or myocardial structure.2-4 A nontransmural MI occurred in a national-caliber swimmer during intense training. Subsequent cardiac catheterization and radionuclide angiographic studies disclosed patent coronary arteries and normal ventricular function.Report of a Case A 20-year-old man, who was a varsity swimmer, complained of severe substernal chest pain while performing a routine 15-km training session. The pain was unaffected by his position or breathing movements are gradually resolved after one hour of rest. He remained asymptomatic until 3 AM the following morning, when he was awakened by similar pain that prompted medical attention.He denied having a
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DELTA (slow wave, stages 3 and 4) sleep has been widely thought of as deep sleep according to criteria involving cerebral responsiveness or ease of arousal.1-5 On the other hand, it is commonly felt that exercise promotes sound or deep sleep, a notion supported by recent experimental studies which indicate the delta sleep-promoting effects of exercise both in animals6,7 and man.8 Although it was shown in this laboratory8 that subjects (Ss) who exercise regularly have more delta sleep on days with exercise than on days without it, it was not possible to determine the duration of the effects of exercise on sleep since the Ss never went without exercise for more than two consecutive days. Hence, we decided to study the sleep of a group of Ss used to regular exercise both while they were exercising and over a relatively prolonged
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The results are reported of a study with healthy male subjects carried out to evaluate the possible association of marginal, biochemical status of vitamins B1, B2, B6 and C with physical performance capacity. It is concluded that biochemical vitamin deficiencies have more than cosmetic value: they really indicate functional impairment.
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Over the past 20 years Soviet research in regeneration has undergone a shift in emphasis from work on amphibians to mammals. In that period several distinct schools of thought have arisen, and often there has been considerable controversy as to the nature of certain regenerative processes. At present most mammalian tissues and organs are being studied with respect to natural regenerative capacity and means of stimulating further regeneration. The most striking results have been obtained in the areas of muscle and bone regeneration. Progress in other areas has been less spectacular. Considerable effort has been put into devising means of regenerating functional tissue from pathologically changed or irradiated organs. The field of regeneration research in the Soviet Union is quite highly organized and includes a relatively large number of workers. Progress has, to some extent, been impeded by shortages of equipment and biochemical preparations.
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• Fear, rage and pain, and the pangs of hunger are all primitive experiences which human beings share with the lower animals. These experiences are properly classed as among the most powerful that determine the action of men and beasts. A knowledge of the conditions which attend these experiences, therefore, is of general and fundamental importance in the interpretation of behavior. During the past four years there has been conducted, in the Harvard Physiological Laboratory, a series of investigations concerned with the bodily changes which occur in conjunction with pain, hunger and the major emotions. A group of remarkable alterations in the bodily economy have been discovered. Because these physiological adaptations are interesting both in themselves and in their interpretation, it has seemed worth while to gather together in convenient form the original accounts of the experiments, which have been published in various American medical and physiological journals. I have, however, attempted to arrange the results and discussions in an orderly and consecutive manner, and I have tried also to eliminate or incidentally to explain the technical terms, so that the exposition will be easily understood by any intelligent reader even though not trained in the medical sciences. (PsycINFO Database Record (c) 2012 APA, all rights reserved) • Fear, rage and pain, and the pangs of hunger are all primitive experiences which human beings share with the lower animals. These experiences are properly classed as among the most powerful that determine the action of men and beasts. A knowledge of the conditions which attend these experiences, therefore, is of general and fundamental importance in the interpretation of behavior. During the past four years there has been conducted, in the Harvard Physiological Laboratory, a series of investigations concerned with the bodily changes which occur in conjunction with pain, hunger and the major emotions. A group of remarkable alterations in the bodily economy have been discovered. Because these physiological adaptations are interesting both in themselves and in their interpretation, it has seemed worth while to gather together in convenient form the original accounts of the experiments, which have been published in various American medical and physiological journals. I have, however, attempted to arrange the results and discussions in an orderly and consecutive manner, and I have tried also to eliminate or incidentally to explain the technical terms, so that the exposition will be easily understood by any intelligent reader even though not trained in the medical sciences. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Eight male subjects (mean age 24.1 +/- 2.6 years) performed at intervals of 2 weeks successively a 3 h and two 2 h runs of different running speed. The days following the running there were moderate elevations of C-reactive protein, haptoglobin, alpha-1-acid glycoprotein, coeruloplasmin, transferrin, alpha-1-antitrypsin and plasminogen. There were small or no changes of albumin, alpha-2-macroglobulin and hemopexin. The elevations of the "acute phase reactants" were examined in three male subjects following a 2 h run before and after an endurance training period of 9 weeks. This demonstrated a decreased acute phase response after training as illustrated by the changes of C-reactive protein, haptoglobin and alpha-1-acid glycoprotein in spite of higher posttraining running speeds. Well-trained athletes have elevated levels of the serum protease inhibitors alpha-1-antitrypsin, alpha-2-macroglobulin and C1-inhibitor. These antiproteolytic glycoproteins might limit exercise-induced inflammatory reactions.
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Two highly trained Black athletes developed haemoptysis during the 90-km Comrades Marathon in 1978 and completed the race with clinical signs of left ventricular failure. For both athletes this was at least the second occurrence of haemoptysis during races longer than 42 km. Chest radiography showed bilateral pulmonary consolidation, upper lobe venous congestion and cardiomegaly in both athletes, one of whom also had a small pleural effusion. Within 36 hours both athletes were clinically better. In one all the radiological abnormalities had disappeared; in the other, heart size had returned to normal, but some pulmonary shadowing remained. The absence in both athletes of other diseases to account for the radiological findings and the rapidity with which these regressed, despite negligible therapy, strongly suggests pulmonary oedema of cardiac origin. Yet conventional cardiological investigation including electrocardiography, echocardiography, phonocardiography, coronary angiography and ventriculography failed to demonstrate cardiac disease in either athlete. As both athletes compete without symptoms in races of up to 42 km, the authors postulate the presence of a cardiac abnormality as yet unrecognized and susceptible to physiological changes which occur only during very prolonged exercise. One possibility is that myocardial compliance becomes progessively impaired during very prolonged exercise. Experimental evidence for this hypothesis is the finding that the rate of myocardial relaxation is, in part, dependent on the rate at which energy can be produced in the glycolytic pathway (the anaerobic metabolism of glycogen or glucose in the cardiac sarcoplasm). During prolonged exercise, a rise in circulating free fatty acids, together with a fall in cardiac glycogen and in serum insulin, would be expected to reduce the rate of glycolytic energy production, thereby reducing the rate of myocardial relaxation. Reduced left ventricular filling due to impaired myocardial compliance, together with the shortened duration of diastole caused by a high exercising rate, might produce left ventricular failure in a structurally normal heart, thus explaining the clinical presentation in these 2 athletes.
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Isometric strength of different muscle groups was recorded in thiryty-nine patients suffering various acute infectious diseases, predominantly of viral or mycoplasma aetiology. Recordings were performed after subsidence of fever, and 1, and 4 months thereafter. A control group of twenty-two healthy men, confined to bed for the same period of time as the patients, were investigated at the same time intervals. In addition, control measurements were performed after 1 year in the patients, prior to bed rest in the control subjects. As a result of illness muscle strength was decreased significantly to 85.4-95.3% of that recorded at 4 months. In the control subjects strength did not change significantly, the corresponding percentages being 96.3-102.5. Thus, the present data indicate that these illnesses in themselves may bring about isometric muscle strength reduction.
The occurrence of possible prolonged alterations in plasma levels of cortisol, epinephrine, norepinephrine, selected energy metabolites, and water and electrolyte balance was assessed in six highly trained male marathon runners by measuring blood biochemical constituents on the 10th day before and for the three days following the running of a marathon. Post-race changes in hemoglobin, hematocrit, and protein levels indicated that a hemodilution had occurred, possibly as a result of elevated sodium levels. Epinephrine remained elevated until the second day. Cortisol was depressed on the first and third post-race days while variable levels were observed on the second day. No prolonged alterations were noted in norepinephrine, FFA, glycerol, triglycerides, glucose, lactate, and pyruvate.
Article
The present study was undertaken to determine what, if any, differential effect various commonly used corticosteroid preparations had on the numbers and specific functions of lymphocyte subpopulations when these agents were administered in equivalent pharmacological dosages. Normal volunteers received a single dose of either 320 mg of hydrocortisone intravenously, 80 mg of prednisone orally, or 12 mg of dexamethasone orally. There was a marked lymphocytopenia and monocytopenia maximal 4-6 hr following administration of all three corticosteroid preparations with almost identical kinetics and degree of fall in total cell numbers as well as proportions of thymus-derived and bone marrow-derived lymphocytes. Hydrocortisone and prednisone caused only a slight suppression of phytohaemagglutiinin (PHA) induced lymphocyte blastogensis which could be reversed at supra-optimal concentrations of PHA. On the contrary, dexamethasone administration casued a marked suppression of PHA responses which was not reversed by supra-optimal PHA stimulation. In addition, hydrocortisone and prednisone administration did not suppress non-specific PHA-induced cellular cytotoxcity, while dexamethasone caused a marked suppression (P less than 0.001) of cytotoxicity. These studies show that although equivalent anti-inflammatory doses of these three corticosteroid preparations cause almost identical suppression of the numbers of circulating lymphocyte populations, they have a differential effect of the numbers of circulating lymphocyte populations, they have a differential effect on a certain in vitro functional correlates of cell-mediated immunity.
Article
Observations were made before and 3-5 days after prolonged endurance jogging an average of 42 miles/day, 6 days/wk for 2.5 mo by a young male adult who voluntarily initiated a run across the United States. Both arterial PO2 and lactic acid increased. In each instance, the first limitation in circulatory delivery of oxygen was a plateau in stroke volume and cardiac output. Afterward, pulse deficit and systemic arterial pressure fell with exercise and heart rate accelerated. Although there was no change in oxygen transport (Q X CAO2), a reduction in stroke volume was exactly balanced by a rise in arterial oxygen content. Vital capacity, residual volume, and total lung capacity and diffusion capacity for carbon monoxide, hematocrit, and red cell mass increased, while plasma volume diminished and heart size and total blood volume were unchanged.
Article
Plasma cortisol, testosterone, androstenedione and LH were determined in 14 men (27–58 years old) taking part in a non-competitive marathon (42.2 km). After the run the mean values showed a rise in cortisol and androstenedione and a fall in testosterone; these changes were statistically highly significant. After the marathon a significant correlation was found between the values for testosterone and androstenedione. Comparisons of the changes in cortisol, testosterone and androstenedione in relation to the control level show that significant correlations existed between the percentage increases in cortisol and androstenedione, and between the percentage decrease in testosterone and percentage increase in androstenedione. Plasma LH response varied, but the mean value after the run did not differ from the mean control value at the same time of day. One very fit subject, who ran the marathon in only 182 min, did not show any decrease in testosterone and his LH increased by more than 100%. One subject, who collapsed after running 15 km, had very low testosterone and LH values, although his cortisol value was unchanged as compared with his control value. The results suggest that during prolonged strenuous exercise LH and androgens, in addition to cortisol, play some role in promoting endurance in men.
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Four corticosteroid hormones were administered (5 mg/kg/day) to rats over 6 to 10 days. Both biochemical and microscopic techniques were employed to determine the influence of these corticosteroids on the fine structure and growth of five striated muscles. Throughout, dexamethasone and triamcinalone were more potent than prednisone or cortisone in influencing muscle growth. The corticosteroids' action on the heart was anabolic, increasing its RNA and protein content. In contrast, the same corticosteroids were catabolic against fast-twitch muscles (e.g., extensor digitorum longus), inducing appreciable atrophy. However, slow-twitch muscles (e.g., soleus) were more resistant to these hormones, exhibiting an intermediate response between that of the heart and fast-twitch muscles. Only minor morphological changes were found in both fast and slow muscles 10 days after the corticosteroid treatments. The hormones' atrophic effects on skeletal muscle primarily arose from the corticosteroid's ability to inhibit protein synthesis, via decreases in the muscles' ribosomal capacities. Whole-body protein synthesis was also suppressed by these corticosteroids, but to a lesser extent than in the whole skeletal musculature.
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Some athletes who undertake strenuous training programs for a prolonged period of time develop the overtraining syndrome. The pathophysiology of the condition is unknown. Hypothalamic-pituitary function was studied by determining the hormonal responses to insulin-induced hypoglycemia in five asymptomatic male marathon runners during a 4-month period in which they ran 42-, 56-, and 92-km races and in four overtrained male athletes. The response of the asymptomatic runners was not different when tested 1 month before and within 48 h after the 42- and 92-km races. All four overtrained athletes presented with impaired training and racing times, apathy, and a heavy-legged feeling and were tested when overtrained and again after 4 weeks of rest. The plasma cortisol, ACTH, GH, and PRL responses to insulin-induced hypoglycemia in the four overtrained athletes were lower than their responses after the rest and lower than the responses of the asymptomatic runners. In both groups, the LH, TSH, and PRL responses to LHRH and TRH were normal. The impaired hormonal responses to insulin-induced hypoglycemia, with recovery after 4 weeks of rest, indicate hypothalamic dysfunction and may be a diagnostic marker of the overtraining syndrome.
Article
A follow-up study of 1 year was performed on 11 male elite weight lifters. Several parameters including training volume, weight lifting performance, and serum hormone concentrations were measured during seven test occasions. In addition, the same measurements were repeated three times during a 6-week period preceding the primary competition, which took place about 5 months after beginning of the follow-up. The primary findings were observed during the 6-week period from which the first 2 weeks of stressful training was associated with significant decreases (P less than 0.01-0.001) in serum testosterone concentration, in testosterone/cortisol and in testosterone/SHBG ratios, and with a significant (P less than 0.001) increase in serum LH concentration. The individual changes during the stressful training in serum testosterone/SHBG ratio were related (r = .63; P less than 0.05) to the individual changes in the weight lifting result in the clean and jerk lift. During the following "normal" 2-week and reduced 2-week training periods, the concentration of serum testosterone remained unaltered, but serum cortisol and serum LH decreased significantly (P less than 0.05-0.01). During these periods, the serum testosterone/SHBG ratio increased (P less than 0.01). The individual changes during this preparatory 4-week training before the primary competition in serum testosterone/SHBG ratio and the individual changes in the weight lifting result in the clean and jerk lift correlated significantly with each other (r = .68; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Article
We have investigated the effect of a 3-month endurance training program (running and cycling) on plasma hormone responses during standardized bicycle ergometer work (15-min consecutive work loads of 60%, 70%, 80%, and eventually 90% V̇O2 max) in eight previously untrained eumenorrheic women. The subjects were investigated before and after training both in the follicular and luteal phases of the menstrual cycle (between the 7th-10th and 20th-25th days of their menstrual cycle, respectively). Blood was obtained 15 and 2 min before the onset of exercise and at the end of each work load from an indwelling catheter. In each sample, the plasma concentrations of estradiol 17β (E2), progesterone (P), testosterone (T), androstenedione (Δ4-A), dehydroepiandrosterone sulfate (DHEA-S), prolactin (PRL), and adrenocorticotropic hormone (ACTH) were assayed in duplicate by RIA; lactate was assayed as well. The hormone concentrations were expressed in absolute as well as in relative values. After training basal DHEA-S and ACTH levels were significantly (P < 0.05) lower in both phases of the menstrual cycle, whereas basal luteal phase E2 and T levels were significantly (0.05 > P > 0.01) lower after training. Exercise induced significant increments in the relative values of ail hormones in both phases (0.05 > P > 0.001). After training, T and DHEA-S increased relatively more pronounced (0.05 > P > 0.02) in the follicular and luteal phase, respectively.
Article
The aim of the present investigation was to compare the changes in plasma estradiol (E2), progesterone (P), luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), androstenedione (delta 4-A), dehydroepiandrosterone sulfate (DHEA-S), adrenocorticotropic hormone (ACTH), and prolactin (PRL) in standardized tests (15-min consecutive work loads of 60%, 70%, 80% VO2 max to exhaustion) in 13 eumenorrheic untrained (UT) and 8 highly trained women (MR). Blood was obtained 15 and 2 min before exercise and at the end of each work load or each 15 min period. The results showed a significant increase (0.05 greater than P less than 0.001, two-way ANOVA) in plasma E2 P, T delta 4-A, PRL, and ACTH both in UT and MR irrespective of the phase of the menstrual cycle. DHEA S levels increased significantly in the MR, but not in the UT, PRL and ACTH increased linearly with exercise in MR and nonlinearly in UT. In the latter group, only the 80% VO2 max work load was able to elicit significant increments in the plasma levels of these hormones. In the MR plasma T and delta 4-A levels increased relatively more pronounced (P less than 0.05) at comparable work loads and exercise times than in the UT. LH levels decreased with exercise both in the UT and MR, whereas FSH levels remained unchanged (MR) or decreased (UT). These findings suggest that during exercise the ovarian hormones are increased by more unspecific mechanisms such as a decreased metabolic clearance rate, whereas in the MR, adrenal secretion of androgens is enhanced.
Article
Intact rats exposed to low or moderate intensity electroshocks for 3-5 h showed a marked increase in plasma ACTH levels 10 min after the beginning of the stress, followed by a decline despite continuous exposure to the stimulus. We have explored the role of steroid feedback, desensitization of the pituitary response to CRF, or changes in pituitary ACTH content in mediating this phenomenon. The following results were obtained. Exposure of adrenalectomized rats to shocks showed that removal of steroid feedback did not restore the ability of the animals to maintain elevated levels of circulating ACTH during electroshocks. To determine whether prolonged stress caused changes in pituitary sensitivity to CRF, intact rats received CRF, epinephrine, vasopressin, or phorbol ester at the end of the 3-h shock session; all secretagogues caused a significantly smaller increase in the plasma ACTH levels in intact rats subjected to low or moderate intensity shocks compared to that of control animals, which suggested that there was no specific desensitization to CRF. By contrast, pituitary responsiveness to CRF was not significantly altered in adrenalectomized rats submitted to low intensity shocks for 1-3 h; however, when moderate intensity shocks were used, adrenalectomized rats showed a blunting of the response to CRF comparable to that in intact animals. Finally, we observed a comparable decrease in the pituitary ACTH content of intact or adrenalectomized rats exposed to electroshocks; this decrease was proportional to the length and intensity of the shocks. We conclude that the inability of continuously stressed rats to maintain elevated plasma ACTH levels appears to be mediated through both the temporary decrease in a readily releasable pituitary ACTH pool and the negative feedback exerted by corticosterone.
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To study the physiologic basis of variability of physical performance in the laboratory, ten male subjects were studied once a week, during a 9-12 month period. Previously, the reference maximal work load attained (Wref) was determined in each subject. The test protocol of the actual study was based on the individual Wref and started at 70% Wref for 5 min whereupon the work load was increased by 5% Wref every 2.5 min to exhaustion. The maximal work load attained (Wmax) was considered as the test performance. Heart rate, respiratory variables, oxygen uptake (VO2), and blood lactate concentration were determined at each work load. The rate of perceived exertion during submaximal and maximal work was also scored. In all subjects, Wmax and VO2max varied randomly, while the coefficient of variation in VO2max (4.20% - 11.35%) exceeded that in Wmax (2.95%-6.83%). No seasonal influences on VO2 max and Wmax were observed. In all subjects the physiologic variables, when plotted as a function of external work load, were shifted to the right with higher Wmax values and to the left with lower Wmax values. With lower Wmax values, the rate of perceived exertion during submaximal work tended to increase. The results suggest that the magnitude of physiologic responses to exercise is related to relative work load and that variability of physical performance is related to changes in gross mechanical efficiency.
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Minute-to-minute fluctuations of serum LH and FSH concentrations resembling a pulsatile pattern were demonstrated in both pre- and post-menopausal women. A pulsatile pattern of LH but not FSH was seen during the menstrual cycle. These appear to follow a varying frequency and magnitude according to the different phases of the cycle; a periodicity of 1–2 hr was seen during the early follicular phase, early luteal phase and midcycle surge while a periodicity of 4 hr was seen in the mid- and late-luteal phase. During the late follicular phase only “minor oscillations” were noted. A greater net increase of circulating LH was found in pulses during the midcycle surge which was more than double that seen during other phases of the cycle. In contrast, post-menopausal subjects had pulses of both gonadotropins. These were usually coincident, however, a minor asynchrony between LH and FSH patterns was discernible. The frequency of pulses in the postmenopausal subjects was the same as in the follicular phase and midc...
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Male hypophysectomized rats were divided into a control group and a group that was subjected to compensatory overload of plantaris muscles for 7 days following surgical removal of synergistic musculature. These groups received daily subcutaneous injections of either cortisone acetate (CA) (100 mg/kg b.wt) or the vehicle for 7 days starting at the time the overload was initiated. Plantaris muscle weights were atrophied by 25% in CA-treated controls, were hypertrophied by 45% in the vehicle-treated overloaded group, and remained similar to vehicle-treated controls in the group receiving both treatments. Scatchard analyses of specific binding of [3H]methyltrienolone (R1881), a synthetic androgen that binds to androgen receptors, were non-linear in plantaris muscle cytosols of vehicle-treated control and overloaded groups and were resolved by a two-component binding model. The lower affinity component, which was attributed to binding of methyltrienolone to a glucocorticoid receptor, disappeared in glucocorticoid-treated rats as evidenced by linear Scatchard plots. Receptor concentrations of the androgenic component of [3H]methyltrienolone binding were unchanged by CA treatment and were significantly increased only in the vehicle-treated overloaded group. [3H]Dexamethasone cytosol binding was increased nearly 2-fold in plantaris muscles of vehicle-treated overloaded animals (64 +/- 3 fmol/mg protein) as compared to those in vehicle-treated controls (32 +/- 2 fmol/mg protein), but was decreased to 2 and 4 fmol/mg protein in the CA-treated controls and CA-treated overloaded groups respectively. These results show that overload and glucocorticoids have opposing actions skeletal muscle, but the overload in the presence of glucocorticoids did not stimulate an increase in androgen cytosol receptor binding.
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Delayed-onset muscular soreness (DOMS), the sensation of pain and stiffness in the muscles that occurs from 1 to 5 d following unaccustomed exercise, can adversely affect muscular performance, both from voluntary reduction of effort and from inherent loss of capacity of the muscles to produce force. This reduction in performance is temporary; permanent impairment does not occur. A number of clinical correlates are associated with DOMS, including elevations in plasma enzymes, myoglobinemia, and abnormal muscle histology and ultrastructure; exertional rhabdomyolysis appears to be the extreme form of DOMS. Presently, the best treatment for DOMS appears to be muscular activity, although the sensation again returns following the exercise. Training for the specific contractile activity that causes DOMS reduces the soreness response. The etiology and cellular mechanisms of DOMS are not known, but a number of hypotheses exist to explain the phenomenon. The following model may be proposed: 1) high tensions (particularly those associated with eccentric exercise) in the contractile/elastic system of the muscle result in structural damage; 2) cell membrane damage leads to disruption of Ca++ homeostasis in the injured fibers, resulting in necrosis that peaks about 2 d post-exercise; and 3) products of macrophage activity and intracellular contents accumulate in the interstitium, which in turn stimulate free nerve endings of group-IV sensory neurons in the muscles leading to the sensation of DOMS.
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Previously it had been shown that there is a sharp increase in C-reactive protein (CRP) serum concentration during the first few days after severe exercise. To evaluate the effect of physical training on the CRP levels, a sensitive enzyme immunoassay was developed and used to assess the basal CRP concentrations in 356 male and 103 female athletes, who trained at least 4 times per week in various disciplines, in 45 male and 40 female untrained controls, and in 35 elderly coronary patients. In male athletes the lowest CRP values were found in swimmers (median: 102 ng/ml, n = 59), which were significantly lower (P < 0.001) than those of male controls (median: 502 ng/ml, n = 45). The CRP concentrations in rowers (median: 260 ng/ml, n = 108) were also significantly lower (P < 0.01) than in the control group. CRP levels in middle- and long-distance runners (median: 315 ng/ml, n = 53), racing cyclists (median: 620 ng/ml, n = 111), and soccer players (median: 660 ng/ml, n = 25) did not differ significantly from those of the controls. In female athletes the lowest CRP concentrations were also found in swimmers (median: 110 ng/ml, n = 49), which were significantly lower (P < 0.001) than those of the female controls (median: 396 ng/ml, n = 40). Female middle- and long-distance runners (n = 36) and female rowers (n = 18) had median CRP values of 250 and 285 ng/ml, respectively. This results suggest that training induces a suppressive effect upon CRP, respqnsible for the low serum levels in athletes (particularly swimmers) when compared to controls. CRP has a broad bacteriostatic action, hence low CRP levels intensively training athletes could be implicated in an increased susceptibility for infections.
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The effect of extremely exhaustive exercise on left ventricular performance was studied echocardiographically in 13 experienced male ultramarathon runners who took part in a competitive 24 hr run, completing distances of 114 to 227 km. Although the left ventricular end-diastolic dimension (EDD) was reduced by 7% (54 +/- 5 to 50 +/- 7 mm; p less than .005), the end-systolic dimension (ESD) increased slightly (33 +/- 5 to 34 +/- 6 mm; NS). As a consequence, the stroke dimension (21 +/- 2 to 16 +/- 2 mm; p less than .005) and fractional shortening (38 +/- 5% to 32 +/- 5%; p less than .005) declined by 24% and 16%, respectively. The reduction in fractional shortening was related to delta ESD (r = -.66; p less than .05) but not to delta EDD (r = .22; NS). In spite of reduced afterload, the mean velocity of circumferential fiber shortening also decreased by an average of 9% (p less than .01) in proportion to the distance completed (r = -.69; p less than .01). The systolic blood pressure/ESD ratio was 21% lower after the race (4.2 +/- 0.9 to 3.3 +/- 0.6; p less than .005). Body weight loss was not related to any alterations in left ventricular dimensions or ejection phase indexes. The stroke dimension and ejection phase indexes continued to decline within the last 6 hr of the race but returned to the prerace level 2 to 3 days after the race. Total serum creatine kinase peaked at 3917 to 64740 U/liter (mean 27427) and its MB percentage peaked at 2% to 6%.(ABSTRACT TRUNCATED AT 250 WORDS)
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Myofibrillar protease activity was found to be elevated, and content of RNA and DNA reduced in m. quadriceps femoris, especially in the fast-twitch white fibers, after dexamethasone treatment. Moderate physical activity prevents, to some extent, the effect of synthetic glucocorticoids. Exhaustive exercise augments the myofibrillar protease activity in both types of muscle fibers. The fast-twitch white type of muscle fibers in exhausted rats are found to have an elevated anticatabolic activity after the treatment of rats with anabolic steroid. It appears that there exists a close correlation between myofibrillar protease activity and muscle weight in the fast-twitch white fibers in dexamethasone treated and exhausted rats.
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Changes in plasma cortisol, androstenedione, testosterone and luteinizing hormone (LH) were measured in five young male sprinters after maximal short-term running and in five young male long-distance runners after moderate (90 min, 4.3 min/km) and intense (45 min, 3.3 min/km) long-term running. Short-term running increased mean plasma cortisol (27%) and androstenedione (19%) significantly; no appreciable changes were found in mean plasma testosterone or LH levels. Intense long-term running caused considerable increases in mean plasma cortisol (43%) and androstenedione (53%). Immediately after the long-term runs mean plasma testosterone and LH did not show nay significant changes, but half an hour later mean plasma LH was found to have dropped significantly below the preceding level, by 42% after the moderate run and by 45% after the intense run. At this time the intense long-term run caused a significant decrease in mean plasma testosterone, which remained depressed up to 3 h after the end of the exercise. This study implies that the changes in plasma hormone levels depend more on the intensity of the exercise than on its duration. The activity of the pituitary-adrenocortical system appears to be a good indicator of the effort expended during the exercise. In the pituitary-testicular system, in contrast, the effort expended may be more accurately reflected by changes during the recovery period.