Skip to main content

Recovery from Overtraining Syndrome: Learnings from the EROS-Longitudinal Study

  • Chapter
  • First Online:
Overtraining Syndrome in Athletes
  • 769 Accesses


Overtraining syndrome (OTS) is an unexplained underperformance syndrome triggered by excessive training, insufficient caloric intake, inadequate sleep, and excessive cognitive and social demands. Besides its unclear pathophysiology, triggers, and biochemical dysfunctions, the investigations of the clinical and biochemical behaviors during the recovery process, as well as specific recommendations and protocols to overcome OTS, have only been recently reported at the EROS-longitudinal study.

From a 12-week interventional protocol in athletes with actual OTS, including increased food intake, transitory interruption of the trainings, improvement of sleep quality, and management of stress, 50 parameters were assessed, including hormonal responses to an insulin tolerance test (ITT), basal hormonal and nonhormonal biochemical markers, body metabolism, and composition.

After 12 weeks of intervention, early cortisol and early and late GH responses to stimulations improved significantly. Cortisol awakening response (CAR) increased by two times, while nocturnal urinary catecholamines (NUC) and CK reduced by two to three times. Basal estradiol reduced while testosterone/estradiol (T:E) ratio increased.

FreeT3 and IGF-1, which were not different than healthy athletes at baseline, disclosed significant increase, whereas ultrasensitive C-reactive protein (usCRP), which was also similar to healthy athletes, has an exacerbated reduction. While all basal parameters and early responses to ITT normalized when compared to healthy athletes, basal metabolic rate, fat oxidation, body fat, muscle mass, and hydration status had partial but non-significant improvements.

In conclusion, athletes affected by actual OTS demonstrated substantial improvements after 12 weeks of intervention, in particular IGF-1, freeT3, CAR, estradiol, testosterone/estradiol ratio, CK and NUC, and early cortisol, early prolactin, and overall GH responses to stimulations. FreeT3, usCRP, and IGF-1 seem to be the sentinel markers of recovery from OTS.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
USD 59.99
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 79.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 109.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions


  1. Meeusen R, Duclos M, Foster C, European College of Sport Science, American College of Sports Medicine, et al. Prevention, diagnosis, and treatment of the overtraining syndrome: Joint Consensus Statement of the European College of Sport Science and the American College of Sports Medicine. Med Sci Sports Exerc. 2013;45(1):186–205.

    PubMed  Google Scholar 

  2. Lehmann M, Foster C, Keul J. Overtraining in endurance athletes: a brief review. Med Sci Sports Exerc. 1993;25(7):854–62.

    CAS  Google Scholar 

  3. Rietjens GJ, Kuipers H, Adam JJ, et al. Physiological, biochemical and psychological markers of strenuous training-induced fatigue. Int J Sports Med. 2005;26(1):16–26.

    CAS  PubMed  Google Scholar 

  4. Cadegiani FA, Kater CE. Hormonal aspects of overtraining syndrome: a systematic review. BMC Sports Sci Med Rehabil. 2017;9:14.

    PubMed  PubMed Central  Google Scholar 

  5. Kreider R, Fry AC, O’Toole M. Overtraining in sport: terms, definitions, and prevalence. In: Kreider R, Fry AC, O’Toole M, editors. Overtraining in sport. Champaign: Human Kinetics; 1998. p. VII–X.

    Chapter  Google Scholar 

  6. Kreher JB, Schwartz JB. Overtraining syndrome: a practical guide. Sports Health. 2012;4(2):128–38.

    PubMed  PubMed Central  Google Scholar 

  7. Fry RW, Morton AR, Keast D. Overtraining in athletes. An update. Sports Med. 1991;12(1):32–65.

    Article  CAS  PubMed  Google Scholar 

  8. Budgett R. Fatigue and underperformance in athletes: the overtraining syndrome. Br J Sports Med. 1998;32:107–10.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Budgett R, Newsholme E, Lehmann M, et al. Redefining the overtraining syndrome as the unexplained underperformance syndrome. Br J Sports Med. 2000;34:67–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Meeusen R, Nederhof E, Buyse L, Roelands B, De Schutter G, Piacentini MF. Diagnosing overtraining in athletes using the two-bout exercise protocol. Br J Sports Med. 2010;44(9):642–8.

    CAS  PubMed  Google Scholar 

  11. Meeusen R, Piacentini MF, Busschaert B, Buyse L, De Schutter G, StrayGundersen J. Hormonal responses in athletes: the use of a two bout exercise protocol to detect subtle differences in (over)training status. Eur J Appl Physiol. 2013;91(2–3):140–6.

    Google Scholar 

  12. Urhausen A, Gabriel HH, Kindermann W. Impaired pituitary hormonal response to exhaustive exercise in overtrained endurance athletes. Med Sci Sports Exerc. 1998;30(3):407–14.

    CAS  PubMed  Google Scholar 

  13. Cadegiani FA, Kater CE. Hypothalamic-pituitary-adrenal (HPA) axis functioning in overtraining syndrome: findings from Endocrine and Metabolic Responses on Overtraining Syndrome (EROS) – EROS-HPA axis. Sports Med Open. 2017;3(1):45.

    PubMed  PubMed Central  Google Scholar 

  14. Cadegiani FA, Kater CE. Growth Hormone (GH) and prolactin responses to a non-exercise stress test in athletes with overtraining syndrome: results from the Endocrine and metabolic Responses on Overtraining Syndrome (EROS) – EROS-STRESS. J Sci Med Sport. 2018;21(7):648–53.

    Article  PubMed  Google Scholar 

  15. Cadegiani FA, Kater CE. Novel causes and consequences of overtraining syndrome: the EROS-DISRUPTORS study. BMC Sports Sci Med Rehabil. 2019;11:21.

    Article  PubMed  PubMed Central  Google Scholar 

  16. Cadegiani FA, Kater CE. Eating, Sleep, and Social Patterns as Independent Predictors of Clinical, Metabolic, and Biochemical Behaviors Among Elite Male Athletes: The EROS-PREDICTORS Study. Front Endocrinol (Lausanne). 2020;11:414. Published 2020 Jun 26.

  17. Cadegiani FA, Kater CE. Inter-correlations among clinical, metabolic, and biochemical parameters and their predictive value in healthy and overtrained male athletes: the EROS-CORRELATIONS study. Front Endocrinol (Lausanne). 2019;10:858.

    Article  Google Scholar 

  18. Cadegiani FA, Kater CE. Body composition, metabolism, sleep, psychological and eating patterns of overtraining syndrome: results of the EROS study (EROS-PROFILE). J Sports Sci. 2018;36(16):1902–10.

    Article  PubMed  Google Scholar 

  19. Cadegiani FA, Kater CE. Basal hormones and biochemical markers as predictors of overtraining syndrome in male athletes: the EROS-BASAL study. J Athl Train. 2019;54:906.

    Article  PubMed  PubMed Central  Google Scholar 

  20. Cadegiani FA, Kater CE. Novel markers of recovery from overtraining syndrome: the EROS-LONGITUDINAL study. Int J Sports Physiol Perform. In review.

    Google Scholar 

  21. Lee S, Farwell AP. Euthyroid sick syndrome. Compr Physiol. 2016;6(2):1071–80.

    PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

Copyright information

© 2020 The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG

About this chapter

Check for updates. Verify currency and authenticity via CrossMark

Cite this chapter

Cadegiani, F. (2020). Recovery from Overtraining Syndrome: Learnings from the EROS-Longitudinal Study. In: Overtraining Syndrome in Athletes. Springer, Cham.

Download citation

  • DOI:

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-52627-6

  • Online ISBN: 978-3-030-52628-3

  • eBook Packages: MedicineMedicine (R0)

Publish with us

Policies and ethics