Veterinary World

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Research (Published online: 18-01-2017)

11. Influence of training and competitive sessions on peripheral β-endorphin levels in training show jumping horses - Cristina Cravana, P. Medica, G. Ragonese and E. Fazio

Veterinary World, 10(1): 67-73



   doi: 10.14202/vetworld.2017.67-73


Cristina Cravana: Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.

P. Medica: Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.

G. Ragonese: Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.

E. Fazio: Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.


Received: 19-09-2016, Accepted: 14-12-2016, Published online: 18-01-2017


Corresponding author: Cristina Cravana, e-mail:

Citation: Cravana C, Medica P, Ragonese G, Fazio E (2017) Influence of training and competitive sessions on peripheral β-endorphin levels in training show jumping horses, Veterinary World, 10(1): 67-73.

Aim: To investigate the effects of training sessions on circulating β-endorphin changes in sport horses before and after competition and to ascertain whether competition would affect this response.

Materials and Methods: A total of 24 trained jumping horses were randomly assigned to one of two training groups: Group A (competing) and Group B (not competing). To determined plasma β-endorphin concentrations, two pre- and postcompetition training weeks at aerobic workout and two competitive show jumping event days at anaerobic workout were measured before, 5 and 30 min after exercise. Exercise intensity is described using lactate concentrations and heart rate. The circuit design, intensity, and duration of training sessions were the same for both groups.

Results: In Group A, one-way analysis of variance for repeated measures (RM-ANOVA) showed significant effects of exercise on β-endorphin changes (F=14.41; p<0.001), only in the post-competition training sessions, while in Group B showed no significant effects. Two-way RM-ANOVA showed, after post-competition training sessions, a significant difference between Group A and Group B (F=6.235; p=0.023), with higher β-endorphin changes in Group A, compared to Group B. During the competitive show jumping sessions, one-way RM ANOVA showed significant effects of exercise on β-endorphin changes (F=51.10; p<0.001). The statistical analysis, in Group A, showed a significant difference between postcompetition training and competitive exercise (F=6.32; p=0.024) with higher β-endorphin values in competitive sessions compared to those of post-competition training.

Conclusion: Lactate concentrations seem to be the main factors being correlated with the raise of β-endorphin during anaerobic exercise of competitive events. Exercise of low intensity, as well as that one of training sessions, does not appear to stimulate a significant increased release of β-endorphin and it may depend on the duration of the exercise program. Moreover, the responses during exercise in the course of post-competition training sessions seem to be significantly different from those the pre-competition training. These data show that the preliminary competitive stress induced additional significant changes of β-endorphin pattern. It would reflect the need of a long-lasting modulation of fatigue and pain perception related to the effect of an additional physical and mental effort for the consecutive competitive and training sessions.

Keywords: β-endorphin, competition, horse, show jumping, training.

1. Medica, P., Cravana, C., Fazio, E. and Ferlazzo, A. (2011) Hormonal responses of quarter horses to a 6-week conventional western-riding training programme. Livest. Sci., 140(1-3): 262-267.
2. Bartolomé, E. and Cockram, M.S. (2016) Potential effects of stress on the performance of sports horses. J. Equine Vet. Sci., 40(5): 84-93.
3. Evans, D.L., Harris, R.C. and Snow, D.H. (1993) Correlation of the racing performance with blood lactate and heart rate after exercise in thoroughbred horses. Equine Vet. J., 25(5): 441-445.
4. Art, T., Franchimont, P. and Lekeux, P. (1994) Plasma β-endorphin response of thoroughbred horses to maximal exercise. Vet. Rec., 135(21): 499-503.
5. Beneke, R., Leithauser, R.M. and Ochentel, O. (2011) Blood lactate diagnostics in exercise testing and training. Int. J. Sports Physiol. Perform., 6(1): 8-24.
6. von Lewinski, M., Biau, S., Erber, R., Ille, N., Aurich, J., Faure, J.M., Möstl, E. and Aurich, C. (2013) Cortisol release, heart rate and heart rate variability in the horse and its rider: Different responses to training and performance. Vet. J., 197(2): 229-232.
7. Golynski, M., Krumrych, W. and Lutnicki, K. (2011) The role of beta-endorphin in horses: A review. Vet. Med., 56(9): 423-429.
8. Ferlazzo, A., Medica, P., Cravana, C. and Fazio, E. (2012) Circulating -endorphin, adrenocorticotropin, and cortisol concentrations of horses before and after competitive show jumping with different fence heights. J. Equine Vet. Sci., 32(11): 740-746.
9. Ferlazzo, A., Fazio, E., Cravana, C. and Medica, P. (2014) Changes of circulating total and free iodothyronines in horses after competitive show jumping with different fence height. J. Equine Vet. Sci., 34(6): 876-881.
10. Veening, J.G. and Barendregt, H.P. (2015) The effects of beta-endorphin: State change modification. Fluids Barriers CNS, 12: 3.
PMid:25879522 PMCid:PMC4429837
11. Bodnar, R.J. (2016) Endogenous opiates and behavior: 2014. Peptides, 75(1): 18-70.
12. Canali, E., Ferrante, V., Mattiello, S., Sacerdote, P., Panerai, A.E. and Lebelt, D. (1996) Plasma levels of β-endorphin and in vitro lymphocyte proliferation as indicators of welfare in horses in normal or restrained conditions. Pferdeheilkunde, 12(4): 415-418.
13. Mehl, M.L., Sarkar, D.K., Schott, H.C. IInd, Brown, J.A., Sampson, S.N. and Bayly, W.M. (1999) Equine plasma beta-endorphin concentrations are affected by exercise intensity and time of day. Equine Vet. J. Suppl., 30: 567-569.
14. Mehl, M.L., Schott, H.C. IInd, Sarkar, D.K. and Bayly, W.M. (2000) Effects of exercise intensity and duration on plasma -endorphin concentrations in horses. Am. J. Vet. Res., 61(8): 969-973.
15. Adler, G.K. (2000) Exercise and fatigue-is neuroendocrinology an important factor? J. Clin. Endocrinol. Metab., 85(6): 2167-2169.
16. Hydbring, E., Nyman, S. and Dahlborn, K. (1996) Changes in plasma cortisol, plasma β-endorphin, heart rate, haematocrit and plasma protein concentration in horses during restraint and use of a naso-gastric tube. Pferdeheilkunde, 12(4): 423-427.
17. Lindner, A., Fazio, E., Medica, P. and Ferlazzo, A. (2002) Effect of age, time record and V4 on plasma cortisol concentration in standardbred racehorses during exercise. Pferdeheilkunde, 18(1): 51-56.
18. Lindner, A., Mosen, H., Kissenbeck, S., Fuhrmann, H. and Sallmann, H.P. (2009) Effect of blood lactate-guided conditioning of horses of differing durations and intensities on heart rate and biochemical blood variables. J. Anim. Sci., 87(10): 3211-3217.
19. Cravana, C., Medica, P., Prestopino, M., Fazio, E. and Ferlazzo, A. (2010) Effects of competitive and noncompetitive show jumping on total and free iodothyronines, β-endorphin, ACTH and cortisol levels of horses. Equine Vet. J. Suppl., 38: 179-184.
20. Fraipont, A., Van Erck, E., Ramery, E., Fortier, G., Lekeux, P. and Art, T. (2012) Assessing fitness in endurance horses. Can. Vet. J., 53(3): 311-314.
PMid:22942450 PMCid:PMC3280789
21. Lindner, A., Fazio, E., Ferlazzo, A.M., Medica, P. and Ferlazzo, A. (2000) Plasma cortisol concentration in thoroughbred horses during and after standardized exercise tests on a treadmill and effects of conditioning on basal cortisol values. Pferdeheilkunde, 16(5): 502-510.
22. Goldfarb, A.H., Hatfield, B.D., Armstrong, D. and Potts, J. (1990) Plasma beta endorphin concentration: Response to intensity and duration of exercise. Med. Sci. Sports Exerc., 22(2): 241-244.
23. Cockrem, J.F. (2013) Individual variation in glucocorticoid stress responses in animal. Gen. Comp. Endocrinol., 181(1): 45-58.
24. Stefánsdóttir, G.I., Ragnarsson, S., Gunnarsson, V. and Jansson, A. (2014) Physiological response to a breed evaluation field test in Icelandic horses. Animal, 8(3): 431-439.
PMid:24387835 PMCid:PMC3942816
25. Viru, M., Hackney, A.C., Karelson, K., Janson, T., Kuus, M. and Viru, A. (2010) Competition effects on physiological response to exercise: Performance, cardiorespiratory and hormonal factors. Acta Physiol. Hung., 97(1): 22-30.
26. Cuhna, G.S., Ribeiro, J.L. and Oliveira, A.R. (2008) Levels of beta-endorphin in response to exercise and overtraining. Arq. Bras. Endocrinol. Metab., 52(4): 589-598.
27. Mercadante, S. (2015) Opioid metabolism and clinical aspects. Eur. J. Pharmacol., 769(11): 71-78.
28. Serrano, M.G., Evans, D.L. and Hodgson, J.L. (2002) Heart rate and blood lactate responses during exercise in preparation for evening competition. Equine Vet. J. Suppl., 34: 135-139.
29. Schwarz, L. and Kindermann, W. (1990) Beta-endorphin, adrenocorticotropic hormone, cortisol and catecholamines during aerobic and anaerobic exercise. Eur. J. Appl. Occup. Physiol., 59(3-4): 165-171.
30. Malinowski, K., Shock, E.J., Rochelle, P., Kearns, C.F., Guirnalda, P.D. and McKeever, K.H. (2006) Plasma β-endorphin, cortisol and immune responses to acute exercise are altered by age and exercise training in horses. Equine Vet. J. Suppl., 36: 267-273.
31. McCarthy, R.N., Jeffcott, L.B., Funder, J.W., Fullerton, M. and Clarke, I.J. (1991) Plasma beta-endorphin and adrenocorticotrophin in young horses in training. Aust. Vet. J., 68(11): 359-361.
32. McCarthy, R.N., Jeffcott, B. and Clarke, I.J. (1993) Preliminary studies on the use of plasma b-endorphin in horses as an indicator of stress and pain. J. Equine Vet. Sci., 13(4): 216-219.
33. Golland, L.C., Evans, D.L., Stone, G.M., Tyler-McGowan, C.M., Hodgson, D.R. and Rose, R.J. (1999) Plasma cortisol and beta-endorphin concentrations in trained and over-trained racehorses. Pflugers Arch., 439(1-2): 11-17.
34. Ferlazzo, A., Medica, P., Cravana, C. and Fazio, E. (2009) Endocrine changes after experimental showjumping. Comp. Exerc. Physiol., 6(2): 59-66.