Journal of the Korea Convergence Society (한국융합학회논문지)

Korea Convergence Society (한국융합학회)
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The Mechanism of Overtraining Syndrome and the Role of Brain Neurotransmitters and Neuromodulators

과훈련 증후군의 기전 및 뇌 신경전달물질과 신경조절물질의 역할

  • Kim, Han-Cheol (Dept. of Special Physical education, Yeungnam University) ;
  • Kim, Woo-Cheol (Dept. of Sports rehabilitation, Daegu Health College) ;
  • Kim, Sung-Woon (Dept. of Physical education, Kyungpook National University)
  • 김한철 (영남대학교 특수체육교육학과) ;
  • 김우철 (대구보건대학교 스포츠재활학과) ;
  • 김성운 (경북대학교 체육교육학과)
  • Received : 2017.10.01
  • Accepted : 2017.11.20
  • Published : 2017.11.28
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Abstract

The purpose of this study was to investigate the existing theories related to overtraining syndrome and to examine the mechanism of overtraining syndrome from the viewpoint of brain science by examining domestic and foreign literature related to the relationship between overtraining syndrome and brain neurotransmitter. The aim of this paper is to provide basic data that can improve the understanding of the mechanism of overtraining syndrome and the role of neurotransmitters and neuromodulators. The results of this study and a number of hypotheses about the overtraining syndrome were proposed, each with strengths and weaknesses. Similar symptoms that occur when the concentration of serotonin in the neurotransmitter increases are related to signs and symptoms of overtraining syndrome. However, it has not been validated to date because it can not distinguish the mechanism of the mediator between the central nervous system and the peripheral nerves. This study suggests that the mechanism of overtraining syndrome will provide important basic information to understand the complex causes of overtraining syndrome through the interaction of existing theory and brain neurotransmitter. Although there has been a lack of studies on the mechanism of overtraining syndrome and brain neurotransmitters so far, we hope that this study will provide an opportunity for more and more people to broaden their understanding of overtraining syndromes.

본 연구의 목적은 과훈련 증후군과 관련된 기존의 이론을 살펴보고, 새로운 접근인 과훈련 증후군 및 뇌신경전달물질과 신경조절물질 간의 역할과 관련된 국내외 문헌들을 고찰하여 스포츠 지도자와 선수들에게 뇌 과학적 관점에서 과훈련 증후군에 대한 이해도를 높일 수 있는 기초자료를 제공하는데 있다. 본 연구결과 과훈련 증후군에 대한 많은 가설들이 제안되었으며, 각각 강점과 약점이 있었다. 그리고 뇌신경 전달 물질인 세로토닌의 농도가 증가 할 때 발생하는 유사한 증상이 과훈련 증후군의 신호와 증상과 관련성이 있는 것으로 나타났다. 하지만 중추신경 또는 말초신경 그 어느 곳에서 매개되는지에 대한 기전을 구별 할 수 없기 때문에 현재까지는 검증 할 수 없었다. 따라서 과훈련 증후군의 기전을 기존의 이론 및 뇌 신경전달물질과 신경조절물질의 상호작용을 통해 알아본 본 연구는 스포츠 현장에서 활동하고 있는 지도자와 선수들에게 과훈련 증후군의 복잡한 원인을 이해시키는데 매우 중요한 기초정보를 제공할 것이라고 판단된다. 물론 지금까지는 과훈련 증후군 기전 및 뇌 신경전달물질과 신경조절물질 간의 연관성에 관한 연구가 많이 부족했지만 본 연구를 통해 조금이나마 더 많은 사람들이 과훈련 증후군에 대한 이해의 폭을 넓히는 계기가 되기를 기대한다.

Keywords

References

  1. L. E. Armstrong, & J. L. Vanheest, "The unknown mechanism of the overtraining syndrome", Sports Medicine, Vol. 32, No. 3, pp. 185-209, 2002. https://doi.org/10.2165/00007256-200232030-00003
  2. L. L. Smith, "Overtraining, excessive exercise, and altered immunity", Sports Medicine, Vol. 33, No, 5, pp. 347-364, 2003. https://doi.org/10.2165/00007256-200333050-00002
  3. S. L. Halson, G. I. Lancaster, A. E. Jeukendrup, & M. Gleeson, "Immunological responses to overreaching in cyclists", Medicine and Science in Sports and Exercise, Vol. 35, No, 5, pp. 854-861, 2003. https://doi.org/10.1249/01.MSS.0000064964.80040.E9
  4. J. B. Kreher, & J. B. Schwartz, "Overtraining syndrome: a practical guide", Sports health, Vol. 4, No. 2, pp. 128-138, 2012. https://doi.org/10.1177/1941738111434406
  5. J. G., Carter, A. W. Potter, & K. A. Brooks, "Overtraining syndrome: causes, con- sequences, and methods for prevention", Journal of Sport and Human Performance, Vol. 2, pp. 1-14, 2014.
  6. A. C. Fry, & W. J. Kraemer, "Resistance exercise overtraining and overreaching", Sports medicine, Vol. 23, No. 2, pp. 106-129, 1997. https://doi.org/10.2165/00007256-199723020-00004
  7. H. Kuipers, "training and overtraining", Medicine & science in sports & Exercise Training, Vol. 30, No. 7, pp. 1137-1139, 1998. https://doi.org/10.1097/00005768-199807000-00018
  8. H. Kuipers, & H. A. Keizer, "Overtraining in elite athletes", Sports Medicine, Vol. 6, No. 2, pp. 79-92, 1988. https://doi.org/10.2165/00007256-198806020-00003
  9. M. Lehmann, C. Foster, & J. Keul, "Overtraining in endurance athletes: a brief review", Medicine & Science in Sports & Exercise, Vol. 25, No. 7, pp. 854-862, 1993. https://doi.org/10.1249/00005768-199307000-00015
  10. J. L. Moeller, "The athlete with fatigue", Current sports medicine reports, Vol. 3, No. 6, pp. 304-309, 2004.
  11. R. Winsley, & N. Matos, "Overtraining and elite young athletes", The elite young athlete, Vol. 56, pp. 97-105, 2011.
  12. C. H. Park, & Y. S. Kwak, "Diagnosis and prevention of the overtraining syndrome", Journal of Coaching Development, Vol. 15, No. 1, pp. 91-97, 2013.
  13. H. Gustafsson, H. C. Holmberg, & P. Hassmen, "An elite endurance athlete's recovery from underperformance aided by a multidisciplinary sport science support team", European Journal of Sport Science, Vol. 8, No. 5, pp. 267-276, 2008. https://doi.org/10.1080/17461390802195652
  14. D. D. Cosca, & F. Navazio, "Common problems in endurance athletes". American Family Physician, Vol. 76, No. 2, pp. 237-244, 2007.
  15. K. Margonis, I. G. Fatouros, A. Z. Jamurtas, M. G. Nikolaidis, I. Douroudos, A. Chatzinikolaou, & D. Kouretas, "Oxidative stress biomarkers responses to physical overtraining: implications for diagnosis", Free Radical Biology and Medicine, Vol. 43, No. 6, pp. 901-910, 2007. https://doi.org/10.1016/j.freeradbiomed.2007.05.022
  16. R. Meeusen, E. Nederhof, L. Buyse, B. Roelands, G. De Schutter, & M. F. Piacentini, "Diagnosing overtraining in athletes using the two-bout exercise protocol", British journal of sports medicine, Vol. 44, No. 9, pp. 642-648, 2010. https://doi.org/10.1136/bjsm.2008.049981
  17. B. K. Pedersen, K. Ostrowski, T. Rohde, & H. Bruunsgaard, "The cytokine response to strenuous exercise", Canadian journal of physiology and pharmacology, Vol. 76, No. 5, pp. 505-511, 1998. https://doi.org/10.1139/y98-055
  18. S. Kayashima, H. Ohno, T. Fujioka, N. Taniguchi, & N. Nagata, "Leucocytosis as a marker of organ damage induced by chronic strenuous physical exercise", European journal of applied physiology and occupational physiology, Vol. 70, No. 5, pp. 413-420, 1995. https://doi.org/10.1007/BF00618492
  19. D. J. Smith, & S. R. Norris, "Changes in glutamine and glutamate concentrations for tracking training tolerance", Medicine and science in sports and exercise, Vol. 32, No. 3, pp. 684-689, 2000. https://doi.org/10.1097/00005768-200003000-00020
  20. L. L. Smith, "Cytokine hypothesis of overtraining: a physiological adaptation to excessive stress?", Medicine & Science in Sports & Exercise, Vol. 32, No. 2, pp. 317-331, 2000. https://doi.org/10.1097/00005768-200002000-00011
  21. R. Meeusen, & K. De Meirleir, "Exercise and brain neurotransmission", Sports Medicine, Vol. 20, No. 3, pp. 160-188, 1995. https://doi.org/10.2165/00007256-199520030-00004
  22. R. Meeusen, M. F. Piacentini, & K. De Meirleir, "Brain microdialysis in exercise research", Sports Medicine, Vol. 31, No. 14, pp. 965-983, 2001. https://doi.org/10.2165/00007256-200131140-00002
  23. R. Meeusen, M. Duclos, M. Gleeson, G. Rietjens, J. Steinacker, & A. Urhausen, "Prevention, diagnosis and treatment of the overtraining syndrome: ECSS position statement task force", European Journal of Sport Science, Vol. 6, No. 01, pp. 1-14, 2006. https://doi.org/10.1080/17461390600617717
  24. R. Budgett, E. Newsholme, M. Lehmann, C. Sharp, D. Jones, T. Jones, & P. White, "Redefining the overtraining syndrome as the unexplained under performance syndrome", British Journal of Sports Medicine, Vol. 34, No. 1, pp. 67-68, 2000. https://doi.org/10.1136/bjsm.34.1.67
  25. P. J. Robson, "Elucidating the unexplained underperformance syndrome in endurance athletes", Sports Medicine, Vol. 33, No. 10, pp. 771-781, 2003. https://doi.org/10.2165/00007256-200333100-00004
  26. E. Nederhof, K. A. Lemmink, C. Visscher, R. Meeusen, & T. Mulder, "Psychomotor speed. Sports medicine", Vol. 36, No. 10, pp. 817-828, 2006. https://doi.org/10.2165/00007256-200636100-00001
  27. R. W. Fry, A. R. Morton, & D. Keast, "Overtraining in athletes", Sports Medicine, Vol. 12, No. 1, pp. 32-65, 1991. https://doi.org/10.2165/00007256-199112010-00004
  28. S. L. Halson, & A. E. Jeukendrup, "Does overtraining exist?", Sports medicine, Vol. 34, No. 14, pp. 967-981, 2004. https://doi.org/10.2165/00007256-200434140-00003
  29. G. Kentta, & P. Hassmen, "Overtraining and recovery", Sports medicine, Vol. 26, No. 1, pp. 1-16, 1998.
  30. H. L. Meehan, S. J. Bull, D. M. Wood, & D. V. James, "The overtraining syndrome: a multicontextual assessment", The Sport Psychologist, Vol. 18, No. 2, pp. 154-171, 2004. https://doi.org/10.1123/tsp.18.2.154
  31. G. Tenenbaum, C. M. Jones, A. Kitsantas, D. N. Sacks, & J. P. Berwick, "Failure adaptation: psychological conceptualization of the stress response process in sport", International Journal of Sport Psychology, Vol. 34, No. 1, pp. 1-26, 2003.
  32. A. C. Snyder, H. A. R. M. Kuipers, B. Cheng, R. O. D. R. I. Q. U. E. Servais, & E. R. I. K. Fransen, "Overtraining following intensified training with normal muscle glycogen. Medicine and science in sports and exercise", Vol. 27, No. 7, pp. 1063-1070, 1995. https://doi.org/10.1249/00005768-199507000-00016
  33. D. L. Costill, M. G. Flynn, J. P. Kirwan, J. A. Houmard, J. B. Mitchell, R. Thomas, & S. H. Park, "Effects of repeated days of intensified training on muscle glycogen and swimming performance", Medicine & Science Sports & Exercise, Vol. 20, No. 3, pp. 249-254, 1988. https://doi.org/10.1249/00005768-198806000-00006
  34. S. L. Hooper, L. T. Mackinnon, & S. J. Hanrahan, "Mood states as an indication of staleness and recovery", International Journal of Sport Psychology, Vol. 28, No. 1, pp. 1-12, 1997.
  35. W. P. Morgan, D. R. Brown, J. S. Raglin, P. J. O'connor, & K. A. Ellickson, "Psychological monitoring of overtraining and staleness", British journal of sports medicine, Vol. 21, No. 3, pp. 107-114, 1987. https://doi.org/10.1136/bjsm.21.3.107
  36. R. Budgett, "Fatigue and under- performance in athletes: the overtraining syndrome", British journal of sports medicine, Vol. 32, No. 2, pp. 107-110, 1998. https://doi.org/10.1136/bjsm.32.2.107
  37. R. Budgett, N. Hiscock, R. Arida, & L. M. Castell, "The effects of the 5-HT2C agonist m-chlorophenylpiperazine on elite athletes with unexplained underperformance syn- drome (overtraining)", British journal of sports medicine, Vol. 44, No. 4, pp. 280-283, 2010. https://doi.org/10.1136/bjsm.2008.046425
  38. L. M. Castell, J. R. Poortmans, R. Leclercq, M. Brasseur, J. Duchateau, & E. A. "Newsholme, Some aspects of the acute phase response after a marathon race, and the effects of glutamine supplementation", European journal of applied physiology and occupational physiology, Vol. 75, No. 1, pp. 47-53, 1996. https://doi.org/10.1007/s004210050125
  39. N. Hiscock, & B. K. Pedersen, "Exercise-induced immunodepression-plasma glutamine is not the link", Journal of Applied Physiology, Vol. 93, No. 3, pp. 813-822, 2002. https://doi.org/10.1152/japplphysiol.00048.2002
  40. N. P. Walsh, A. K. Blannin, P. J. Robson, & M. Gleeson, "Glutamine, exercise and immune function", Sports Medicine, Vol. 26, No. 3, pp. 177-191, 1998.
  41. L. T. Mackinnon, & S. L. Hooper, "Plasma glutamine and upper respiratory tract infection during intensified training in swimmers", Medicine and science in sports and exercise, Vol. 28, No. 3, pp. 285-290, 1996. https://doi.org/10.1097/00005768-199603000-00003
  42. P. M. Tiidus, "Radical species in inflammation and overtraining", Canadian journal of physiology and pharmacology, Vol. 76, No. 5, pp. 533-538, 1998. https://doi.org/10.1139/y98-047
  43. M. Tanskanen, M. Atalay, & A. Uusitalo, "Altered oxidative stress in overtrained athletes", Journal of sports sciences, Vol. 28, No. 3, pp. 309-317, 2010. https://doi.org/10.1080/02640410903473844
  44. R. Hohl, R. L. P. Ferraresso, R. B., De Oliveira, R. Lucco, R., Brenzikofer, & D. V. De Macedo, "Development and characterization of an overtraining animal model", Medicine & Science in Sports & Exercise, Vol. 41, No. 5, pp. 1155-1163, 2009. https://doi.org/10.1249/MSS.0b013e318191259c
  45. C. GouarnE, C. Groussard, A. Gratas -delamarche, P. Delamarche, & M. Duclos, "Overnight urinary cortisol and cortisone add new insights into adaptation to training", Medicine & Science in Sports & Exercise, Vol. 37, No. 7, pp. 1157-1167, 2005. https://doi.org/10.1249/01.mss.0000170099.10038.3b
  46. A. Urhausen, & W. Kindermann, "Diagnosis of overtraining", Sports medicine, Vol. 32, No. 2, pp. 95-102, 2002. https://doi.org/10.2165/00007256-200232020-00002
  47. E. S. A. Hynynen, A. Uusitalo, N. Konttinen, & H. Rusko, "Heart rate variability during night sleep and after awakening in overtrained athletes", Medicine & science in sports & exercise, Vol. 38, No. 2, pp. 313-317, 2006. https://doi.org/10.1249/01.mss.0000184631.27641.b5
  48. V. Pichot, F. Roche, J. M. Gaspoz, F. Enjolras, A. Antoniadis, P. Minini, & J. C. Barthelemy, "Relation between heart rate variability and training load in middle- distance runners", Medicine and science in sports and exercise, Vol. 32, No. 10, pp. 1729-1736, 2000. https://doi.org/10.1097/00005768-200010000-00011
  49. A. Angeli, M. Minetto, A. Dovio, & P. Paccotti, "The overtraining syndrome in athletes: a stress-related disorder", Journal of endocrinological investigation, Vol. 27. No. 6, pp. 603-612. 2004. https://doi.org/10.1007/BF03347487
  50. K. M. Edwards, V. E. Burns, C. Ring, & D. Carroll, "Individual differences in the interleukin-6 response to maximal and submaximal exercise tasks", Journal of sports sciences, Vol. 24, No. 8, pp. 855-862, 2006. https://doi.org/10.1080/02640410500245645
  51. R. Meeusen, P. Watson, H. Hasegawa, B. Roelands, & M. F. Piacentini, "Central fatigue-the serotonin hypothesis and beyond", Sports Medicine. Vol. 36, pp. 881-909, 2006. https://doi.org/10.2165/00007256-200636100-00006
  52. R. Meeusen, & M. F. Piacentini, "Exercise, fatigue, neurotransmission and the influence of the neuroendocrine axis", Advances in experimental medicine and biology, Vol. 527, pp. 521-525, 2003.
  53. L. Nybo, & N. H. Secher, "Cerebral perturbations provoked by prolonged exercise", Progress in neurobiology, Vol. 72, No. 4, pp. 223-261, 2004. https://doi.org/10.1016/j.pneurobio.2004.03.005
  54. R. Meeusen, "Overtraining and the central nervous system, the missing link. Overload, performance incompetence, and regeneration in sport", New York: Kluwer Academic/Plenum publishers, 187-202, 1999.
  55. A., Fry, J., Steinacker, & R. Meeusen, Central mechanisms of overtraining endocrinology. In The endocrine system in sports and exercise. Edited by W.J. Kraemer and A.D. Rogol. Blackwell Publishing. pp. 578-599. (2006).
  56. J. D. Barchas, & D. X. "Freedman, Brain amines: response to physiological stress", Biochemical pharmacology, Vol. 12, No. 10, pp. 1232-1235, 1963. https://doi.org/10.1016/0006-2952(63)90101-1
  57. K. E. Moore, & E. W. Lariviere, "Effects of stress and d-amphetamine on rat brain catecholamines", Biochemical pharmaco- logy, Vol. 13, No. 7, pp. 1098- 1100, 1964. https://doi.org/10.1016/0006-2952(64)90107-8
  58. Acworth(1986)Acworth, I., Nicholass, J., Morgan, B., & Newsholme, E. A. (1986). Effect of sustained exercise on concentrations of plasma aromatic and branched-chain amino acids and brain amines. Biochemical and biophysical research communications, 137(1), 149-153. https://doi.org/10.1016/0006-291X(86)91188-5
  59. E. A. Newsholme, I. Acworth, & E. Blomstrand, "Amino acids, brain neurotransmitters and a function link between muscle and brain that is important in sustained exercise". In Advances in myochemistry. Edited by G. Benzi. John Libbey Eurotext, London, UK. pp. 127-133, 1987.
  60. F. Bequet, D. Gomez‐Merino, M. Berthelot, & C. Y. Guezennec, "Evidence that brain glucose availability influences exercise‐enhanced extracellular 5‐HT level in hippocampus: a microdialysis study in exercising rats", Acta Physiologica, Vol. 176, No. 1, pp. 65-69, 2002. https://doi.org/10.1046/j.1365-201X.2002.01015.x
  61. J. M. Davis, & S. P. Bailey, "Possible mechanisms of central nervous system fatigue during exercise", Medicine and science in sports and exercise, Vol. 29, No. 1, pp. 45-57, 1997. https://doi.org/10.1097/00005768-199701000-00008
  62. S. C. Gandevia, "Spinal and supraspinal factors in human muscle fatigue", Physiological reviews, Vol. 81, No. 4, pp. 1725-1789, 2001. https://doi.org/10.1152/physrev.2001.81.4.1725
  63. J. D. Fernstrom, "Role of precursor availability in control of monoamine biosynthesis in brain", Physiological reviews, Vol. 63, No. 2, pp. 484-546, 1983. https://doi.org/10.1152/physrev.1983.63.2.484
  64. E. Blomstrand, P. Ek S. Hassmen, B. Ekblom, & E. A. Newsholme, "Influence of ingesting a solution of branched‐chain amino acids on perceived exertion during exercise", Acta Physiologica, Vol. 159, No. 1, pp. 41-49, 1997. https://doi.org/10.1046/j.1365-201X.1997.547327000.x
  65. P. Hassmen, E. Blomstrand, B. Ekblom, & E. A. Newsholme, "Branched-chain amino acid supplementation during 30-km competitive run: mood and cognitive performance", Nutrition (Burbank, Los Angeles County, Calif.), Vol. 10, No. 5, pp. 405-410, 1994.
  66. G. Van Hall, J. S. Raaymakers, W. H. Saris, & A. J. Wagenmakers, "Ingestion of branched‐chain amino acids and tryptophan during sustained exercise in man: failure to affect performance", The Journal of Physiology, Vol. 486, No. 3, pp. 789-794, 1995. https://doi.org/10.1113/jphysiol.1995.sp020854
  67. E. Blomstrand, S. Andersson, P. A. Hassmen, B. Ekblom, & E. A. Newsholme, "Effect of branchedchain amino acid and carbohydrate supplementation on the exercise‐induced change in plasma and muscle concentration of amino acids in human subjects", Acta Physiologica, Vol. 153, No. 2, pp. 87-96, 1995. https://doi.org/10.1111/j.1748-1716.1995.tb09839.x
  68. H. K. Strüder, W. Hollmann, P. Platen, M. Donike, A. Gotzmann, & K. Weber, "Influence of paroxetine, branched-chain amino acids and tyrosine on neuroendocrine system responses and fatigue in humans", Hormone and Metabolic Research, Vol. 30, No. 04, pp. 188-194, 1998. https://doi.org/10.1055/s-2007-978864
  69. M. F. Piacentini, R. O. M. A. I. N. Meeusen, L. Buyse, G. De Schutter, F. A. R. I. D. Kempenaers, J. Van Nijvel, & K. De Meirleir, "No effect of a noradrenergic reuptake inhibitor on performance in trained cyclists", Medicine and science in sports and exercise, Vol. 34, No. 7, pp. 1189-1193, 2002. https://doi.org/10.1097/00005768-200207000-00021
  70. S. C. Gandevia, "Spinal and supraspinal factors in human muscle fatigue", Physiological reviews, Vol. 81, No. 4, pp. 1725-1789, 2001. https://doi.org/10.1152/physrev.2001.81.4.1725
  71. P. Watson, H. Hasegawa, B. Roelands, M. F. Piacentini, R. Looverie, & R. Meeusen, "Acute dopamine/noradrenaline reuptake inhibition enhances human exercise performance in warm, but not temperate conditions", The Journal of physiology, Vol. 565, No. 3, pp. 873-883, 2005. https://doi.org/10.1113/jphysiol.2004.079202
  72. H. Hasegawa, R. Meeusen, S. Sarre, M. Diltoer, M. F. Piacentini, & Y. Michotte, "Acute dopamine/norepinephrine reuptake inhibition increases brain and core temperature in rats", Journal of Applied Physiology, Vol. 99, No. 4, pp. 1397-1401, 2005. https://doi.org/10.1152/japplphysiol.00435.2005
  73. M. Lehmann, C. Foster, U. Gastmann, H. Keizer, & J. M. Steinacker, "Definition, Types, Symptoms, Findings, Underlying Mechanisms, and Frequency of Overtraining and Overtraining Syndrome", Overload, Performance Incompetence, and Regeneration in Sport, pp. 1-6, 1999.
  74. S. L. Halson, M. W. Bridge, R. Meeusen, B. Busschaert, M. Gleeson, D. A. Jones, & A. E. Jeukendrup, "Time course of performance changes and fatigue markers during intensified training in trained cyclists", Journal of applied physiology, Vol. 93, No. 3, pp. 947-956, 2002. https://doi.org/10.1152/japplphysiol.01164.2001
  75. A. E. Jeukendrup, M. K. C. Hesselink, A. C. Snyder, H. Kuipers, & H. A. Keizer, "Physiological changes in male competitive cyclists after two weeks of intensified training", International journal of sports medicine, Vol. 13, No. 07, pp. 534-541, 1992. https://doi.org/10.1055/s-2007-1021312
  76. H. A. Keizer, "Neuroendocrine aspects of overtraining", Overtraining in sport, pp. 145-68, 1998.
  77. J. M. Steinacker, W. Lormes, M. Kellmann, Y. Liu, S. Reissnecker, A. Opitz-Gress, & M. Lehmann, "Training of junior rowers before world championships. Effects on performance, mood state and selected hormonal and metabolic responses", The Journal of sports medicine and physical fitness, Vol. 40, No. 4, pp. 327-335, 2000.
  78. A. X. E. L. Urhausen, H. H. Gabriel, & W. Kindermann, "Impaired pituitary hormonal response to exhaustive exercise in overtrained endurance athletes", Medicine and science in sports and exercise, Vol. 30, No. 3, pp. 407-414, 1998. https://doi.org/10.1097/00005768-199803000-00011
  79. W. P. Morgan, D. L. Costill, M. G. Flynn, J. S. Raglin, & P. J. O'Connor, "Mood disturbance following increased training in swimmers", Medicine and science in sports and exercise, Vol. 20, No. 4, pp. 408-414, 1988. https://doi.org/10.1249/00005768-198808000-00014
  80. T. Wilckens, U. Schweiger, & K. M. Pirke, "Activation of 5-HT 1C-receptors suppresses excessive wheel running induced by semi-starvation in the rat", Psycho- pharmacology, Vol. 109, No. 1, pp. 77-84, 1992. https://doi.org/10.1007/BF02245483
  81. A. L. Dunn, & R. K. Dishman, "Exercise and the Neurobiology of Depression. Exercise and sport sciences reviews", Vol. 19, No. 1, pp. 41-98, 1991.
  82. F. Chaouloff, "Physiopharmacological interactions between stress hormones and central serotonergic systems", Brain Research Reviews, Vol. 18, No. 1, pp. 1-32, 1993. https://doi.org/10.1016/0165-0173(93)90005-K
  83. R. Dishman, "The norepinephrine hypothesis. In Physical activity & mental health", Edited by W. P. Morgan. Taylor & Francis, Washington. pp. 199-212, 1997.