Diagnosing Overtraining Syndrome: A Scoping Review

Context: Overtraining syndrome (OTS) is a condition characterized by a long-term performance decrement, which occurs after a persisting imbalance between training-related and nontraining-related load and recovery. Because of the lack of a gold standard diagnostic test, OTS remains a diagnosis of exclusion. Objective: To systematically review and map biomarkers and tools reported in the literature as potentially diagnostic for OTS. Data Sources: PubMed, Web of Science, and SPORTDiscus were searched from database inception to February 4, 2021, and results screened for eligibility. Backward and forward citation tracking on eligible records were used to complement results of database searching. Study Selection: Studies including athletes with a likely OTS diagnosis, as defined by the European College of Sport Science and the American College of Sports Medicine, and reporting at least 1 biomarker or tool potentially diagnostic for OTS were deemed eligible. Study Design: Scoping review following the guidelines of the Joanna Briggs Institute and PRISMA Extension for Scoping Reviews (PRISMA-ScR). Level of Evidence: Level 4. Data Extraction: Athletes’ population, criteria used to diagnose OTS, potentially diagnostic biomarkers and tools, as well as miscellaneous study characteristics were extracted. Results: The search yielded 5561 results, of which 39 met the eligibility criteria. Three diagnostic scores, namely the EROS-CLINICAL, EROS-SIMPLIFIED, and EROS-COMPLETE scores (EROS = Endocrine and Metabolic Responses on Overtraining Syndrome study), were identified. Additionally, basal hormone, neurotransmitter and other metabolite levels, hormonal responses to stimuli, psychological questionnaires, exercise tests, heart rate variability, electroencephalography, immunological and redox parameters, muscle structure, and body composition were reported as potentially diagnostic for OTS. Conclusion: Specific hormones, neurotransmitters, and metabolites, as well as psychological, electrocardiographic, electroencephalographic, and immunological patterns were identified as potentially diagnostic for OTS, reflecting its multisystemic nature. As exemplified by the EROS scores, combinations of these variables may be required to diagnose OTS. These scores must now be validated in larger samples and within female athletes.

Intra-Season Variations in Workload Parameters in Europe’s Elite Young Soccer Players: A Comparative Pilot Study between Starters and Non-starters

Background: The main purpose of the current study was to compare the within-season variations of workload, training duration, acute/chronic workload ratio (ACWR), training monotony ™, and training strain (TS) through session rating perceived exertion (s-RPE) between starters and non-starters. Methods: Seventeen under-17 European male soccer players (age, 16.2 ± 0.3 y, height, 1.8 ± 0.1 m; body mass, 66.5 ± 4.0 kg) divided in two groups: nine starters and eight non-starters, were evaluated over 50 weeks throughout the season. Results: In general, there were load variations for all players during the full-season. RPE tended to decrease during in-season and RPE, training duration and s-RPE did not present significant differences between starters and non-starters. TM and TS presented lower values for starters in mesocycle (M) 4 and M11 compared to non-starters. TS presented lower values for starters in M4 and M11 compared to non-starters, while in M10 a higher value was found for starters when compared to non-starters. ACWR showed differences between starters and non-starters in two of the mesocycles. Conclusions: This study showed that some mesocycles provided higher load for non-starters. This information can alert coaches that non-starter players are likely to try too hard in training to demonstrate their abilities, leading to non-functional overreaching, overtraining syndrome, and then poor performance.

Psychological Context of Overtraining Syndrome in Elite Athletes in Adolescence: Literature Review

The article presents an overview of important findings concerning the overtraining syndrome (OTS) in elite athletes. Although the scientific community agrees that OTS is a multifactorially determined and individually variable phenomenon, which can have a serious impact on the individual, there are still some inconsistencies. Therefore, in our study we focused on the terminology of the phenomenon, its prevalence, etiology and symptomatology. We paid specific attention to psychological instruments of detecting OTS indicators. Given that in the period of adolescence the training process in the majority of sport disciplines intensifies significantly, the context of developmental changes during this period in relation to OTS is discussed. The final part of the study summarizes the basic principles of prevention of this pathological phenomenon.

Plasma irisin and its associations with oxidative stress in athletes suffering from overtraining syndrome

Irisin is a novel exercise-induced myokine that may be involved in regulating energy metabolism. We determined whether overtraining syndrome (OTS) and its biochemical markers are associated with plasma irisin levels in athletes. Seven severely overtrained athletes (OA) and 10 healthy control athletes (CA) were recruited and examined at the time of diagnosis (baseline) and after 6- and 12-months follow-up. Training volume and intensity were initially restricted but progressively increased in OA as OTS symptoms alleviated; CA continued their normal training routine. A maximal cycle ergometer test was performed with irisin analyzed before and after the test. Before the exercise test, irisin levels tended to be lower in OA than in CA at baseline (154.5 ± 28.5 vs. 171.7 ± 58.7 ng/mL). In both groups, at rest irisin levels changed only marginally during follow-up and were not affected by maximal exercise, nor were they associated with physical performance or body fat percentage. Irisin concentration at rest correlated positively with an oxidative stress marker, malondialdehyde (MDA) and negatively with an antioxidant protection marker, oxygen radical absorbance capacity (ORAC) in response to the exercise test in OA at baseline. Our findings help to clarify the possible contribution of irisin and its association with oxidative stress in the pathophysiology of OTS.

OVERTRAINING SYNDROME IN ATHLETES

Aim: The aim of our study is to reveal the effect of training overload on athletes. Overtraining syndrome (overtraining) is a very difficult, systemic and complex condition to diagnose. This syndrome occurs with decrease in performance, fatigue, deterioration in sleep patterns, and changes in social behavior when the training load increases unconsciously. Many factors affect the rate and recovery time of overtraining syndrome. These factors are the result of continuous loading, load differential, load tolerance and recovery. The coach needs to plan both the training and the recovery process well. Because optimal performance depends on maintaining the delicate balance between training and recovery. Method: Our study is a compilation obtained to provide information from studies on overtraining syndrome. Findings: In the literature, the symptoms of overtraining are examined under 3 headings as sympathetic, parasympathetic and other symptoms. Conclusion: In order to prevent overtraining syndrome, it is necessary to avoid possible effects that harm team performance. Trainers can facilitate this by changing the training period with the recovery period. In addition, they can help their athletes get rid of this syndrome by using techniques such as mild aerobic activities, massage, hot and cold baths, diet, adequate sleep and psychological relaxation. Recommendation: Nutrition, sleep and rest patterns, recovery efforts (regeneration), emotional support, oxygen administration, medication, etc. are the factors that can treat overtraining syndrome.

Does personality matter when we are approaching the subjective perception of overtraining among adolescents?

This article deals with the issue of overtraining among elite adolescent athletes. The aim of our study was to examine the relationship between certain personality traits, as perfectionism, extraversion, neuroticism and other Big 5 traits and subjective perception of training load (which is one of the best indicator of overtraining syndrome). We also focused on the relationship between a perceived training difficulty and perceived training load too find out, if there is some kind of integral relationship. To collect data we used a questionnaire, which were given to adolescent elite athletes playing team sports in a mid-season period. The results show significant relationship between perceived training load and overall perfectionism (r=0.189, p<0.001), extraversion (r=-0.241, p<0.001), neuroticism (r=0.343, p<0.001) and consciousness (r=-0.287, p<0.001). After the closer examination we found an interesting relation between single dimension of perfectionism and perceived training load, suggesting the contribution of maladaptive perfectionism on development of overtraining syndrome. Besides that, we differentiated athletes into two groups, according to the level of perceived training difficulty. Those, who perceived training as difficult to exhausting (M=2,19, SD=0.50) were significantly higher than low to medium group (M=1.99, SD=0.47) in the perceived training load t(178)=-0.894, p=0.007. Those results extend our knowledge of overtraining topic and can be used in coaching practice to help identify athletes with higher risk of overtraining, or even prevent these states among young athletes before they occur. Hereby results suggest the importance of psychological aspects in sport preparation.

OVERTRAINING IN STUDENT-ATHLETES: DO COACHES AND PARENTS “PUSH TOO HARD?”

The occurrence of the overtraining syndrome emerges as one of the most important issues in sport. The objective of this study is to determine the prevalence of overtraining in sport university students and to examine the connection between the occurrence of this phenomenon and the behavior of coaches and parents. The study includes 107 students who have been competing in sport disciplines for more than two years. The results indicate that 19.6% of them have experienced overtraining syndrome and that the syndrome is more likely to occur in men and athletes who train individual sports. Overtraining occurs in one third of the athletes by the age of seventeen. Overtrained athletes perceive coaches and parents as individuals who push too hard. Suggestions for changing the behavior of coaches and parents of young athletes with the aim of preventing the occurrence of overtraining have been discussed.

Assessment of exercise-induced stress by automated measurement of salivary cortisol concentrations within the circadian rhythm in Japanese female long-distance runners

Background: Overtraining syndrome, caused by prolonged excessive stress, results in reduced performance and cortisol responsiveness in athletes. It is necessary to collect saliva samples sequentially within circadian rhythm for assessing exercise stress by measuring cortisol concentrations, and automated cortisol measurements using electrochemiluminescence immunoassay (ECLIA) may be useful for measuring a large number of saliva samples. In this study, we evaluated the appropriate use of cortisol-based exercise stress assessment within the circadian rhythm, which may diagnose and prevent overtraining syndrome in athletes. Methods: We collected saliva and sera from 54 healthy participants and analyzed the correlation between salivary cortisol concentrations measured by ECLIA and enzyme-linked immunosorbent assay (ELISA) or serum cortisol analysis. We also collected saliva continuously from 12 female long-distance runners on 2 consecutive days involving different intensities and types of exercise early in the morning and in the afternoon and measured salivary cortisol concentrations using ECLIA. Each exercise intensity of runners was measured by running velocities, Borg Scale score, and rate of change in the pulse rate by exercise. Results: ECLIA-based salivary cortisol concentrations correlated positively with those detected by ELISA (ρ = 0.924, p < 0.001) and serum cortisol (ρ = 0.591, p = 0.001). In long-distance runners, circadian rhythm of salivary cortisol including peak after waking and decrease promptly thereafter were detected on both days by continuous saliva sampling. The rates of change in salivary cortisol concentrations were significantly lower after an early morning exercise than after an afternoon exercise on both days (day 1, p = 0.002 and day 2, p = 0.003). In the early morning exercise, the rate of change in salivary cortisol concentration was significantly higher on day 1 than on day 2 ( p = 0.034), similar to significant difference in running velocities ( p = 0.001).Conclusions: Our results suggest that automated ECLIA-based salivary cortisol measurements are able to detect the athletes' circadian rhythm and compare the exercise stress intensities at the same times on different days, even in the early morning, possibly leading to prevention of overtraining syndrome.