Training Load, Immune Status, and Clinical Outcomes in Young Athletes: A Controlled, Prospective, Longitudinal Study
- PMID: 29628891
- PMCID: PMC5876235
- DOI: 10.3389/fphys.2018.00120
Training Load, Immune Status, and Clinical Outcomes in Young Athletes: A Controlled, Prospective, Longitudinal Study
Abstract
Introduction: Beside positive effects on athlete's health, competitive sport can be linked with an increased risk of illness and injury. Because of high relative increases in training, additional physical and psychological strains, and an earlier specialization and professionalization, adolescent athletes needs an increased attention. Training can alter the immune system by inducing a temporary immunosuppression, finally developing infection symptoms. Previous studies identified Epstein Barr Virus (EBV) as potential indicator for the immune status. In addition to the identification of triggering risk factors for recurrent infections, the aim was to determine the interaction between training load, stress sense, immunological parameters, and clinical symptoms. Methods: A controlled, prospective, longitudinal study on young athletes (n = 274, mean age: 13.8 ± 1.5 yrs) was conducted between 2010 and 2014. Also 285 controls (students, who did not perform competitive sports, mean age: 14.5 ± 1.9 yrs) were recruited. Athletes were examined 3 times each year to determine the effects of stress factors (training load: training hours per week [Th/w]) on selected outcome parameters (clinical [susceptibility to infection, WURSS-21: 21-item Wisconsin Upper Respiratory Symptom Survey], immunological, psychological end points). As part of each visit, EBV serostatus and EBV-specific IgG tiers were studied longitudinally as potential immune markers. Results: Athletes (A) trained 14.9 ± 5.6 h weekly. Controls (C) showed no lower stress levels compared to athletes (p = 0.387). Twelve percent of athletes reported recurrent infections (C: 8.5%, p = 0.153), the presence of an upper respiratory tract infection (URTI) was achieved in 30.7%. EBV seroprevalence of athletes was 60.3% (C: 56.6%, p = 0.339). Mean EBV-specific IgG titer of athletes was 166 ± 115 U/ml (C: 137 ± 112 U/ml, p = 0.030). With increasing Th/w, higher stress levels were observed (p < 0.001). Analyzes of WURSS-21 data revealed no relationship to training load (p = 0.323). Also, training load had no relation to EBV serostatus (p = 0.057) or the level of EBV-specific IgG titers (p = 0.364). Discussion: Young elite athletes showed no increased sense of stress, no higher prevalence of recurrent infections, and no different EBV-specific serological parameters compared to controls. Also, no direct relationship between training loads, clinical complaints, and EBV-specific immune responses was found. With increasing training loads athletes felt more stressed, but significant associations to EBV-specific serological parameters were absent. In summary, EBV serostatus and EBV-specific IgG titers do not allow risk stratification for impaired health. Further investigations are needed to identify additional risk factors and immune markers, with the aim to avoid inappropriate strains by early detection and following intervention.
Keywords: EBV; URTI; athlete; immune system; infection; stress; susceptibility; training load.
Figures
![Figure 1](https://cdn.statically.io/img/www.ncbi.nlm.nih.gov/pmc/articles/instance/5876235/bin/fphys-09-00120-g0001.gif)
![Figure 2](https://cdn.statically.io/img/www.ncbi.nlm.nih.gov/pmc/articles/instance/5876235/bin/fphys-09-00120-g0002.gif)
![Figure 3](https://cdn.statically.io/img/www.ncbi.nlm.nih.gov/pmc/articles/instance/5876235/bin/fphys-09-00120-g0003.gif)
![Figure 4](https://cdn.statically.io/img/www.ncbi.nlm.nih.gov/pmc/articles/instance/5876235/bin/fphys-09-00120-g0004.gif)
![Figure 5](https://cdn.statically.io/img/www.ncbi.nlm.nih.gov/pmc/articles/instance/5876235/bin/fphys-09-00120-g0005.gif)
Similar articles
-
Influence of CMV/EBV serostatus on respiratory infection incidence during 4 months of winter training in a student cohort of endurance athletes.Eur J Appl Physiol. 2013 Oct;113(10):2613-9. doi: 10.1007/s00421-013-2704-x. Epub 2013 Aug 7. Eur J Appl Physiol. 2013. PMID: 23922172
-
Elevated Epstein-Barr virus loads and lower antibody titers in competitive athletes.J Med Virol. 2010 Mar;82(3):446-51. doi: 10.1002/jmv.21704. J Med Virol. 2010. PMID: 20087932
-
Identification of Potential Performance-Related Predictors in Young Competitive Athletes.Front Physiol. 2019 Nov 15;10:1394. doi: 10.3389/fphys.2019.01394. eCollection 2019. Front Physiol. 2019. PMID: 31803061 Free PMC article.
-
American Medical Society for Sports Medicine position statement: concussion in sport.Br J Sports Med. 2013 Jan;47(1):15-26. doi: 10.1136/bjsports-2012-091941. Br J Sports Med. 2013. PMID: 23243113 Review.
-
Developmental Training Model for the Sport Specialized Youth Athlete: A Dynamic Strategy for Individualizing Load-Response During Maturation.Sports Health. 2022 Jan-Feb;14(1):142-153. doi: 10.1177/19417381211056088. Epub 2021 Nov 11. Sports Health. 2022. PMID: 34763556 Free PMC article. Review.
Cited by
-
Acute and chronic effects of physical exercise on IgA and IgG levels and susceptibility to upper respiratory tract infections: a systematic review and meta-analysis.Pflugers Arch. 2022 Dec;474(12):1221-1248. doi: 10.1007/s00424-022-02760-1. Epub 2022 Oct 17. Pflugers Arch. 2022. PMID: 36251066 Free PMC article.
-
Part I: Relationship among Training Load Management, Salivary Immunoglobulin A, and Upper Respiratory Tract Infection in Team Sport: A Systematic Review.Healthcare (Basel). 2021 Mar 24;9(4):366. doi: 10.3390/healthcare9040366. Healthcare (Basel). 2021. PMID: 33805186 Free PMC article. Review.
-
Effect of concurrent training on trainability performance factors in youth elite golf players.PeerJ. 2020 Sep 16;8:e9963. doi: 10.7717/peerj.9963. eCollection 2020. PeerJ. 2020. PMID: 32995097 Free PMC article.
-
Upper respiratory tract symptoms and salivary immunoglobulin A of elite female gymnasts: a full year longitudinal field study.Biol Sport. 2020 Sep;37(3):285-293. doi: 10.5114/biolsport.2020.95639. Epub 2020 Jun 10. Biol Sport. 2020. PMID: 32879551 Free PMC article.
-
Alterations in the innate immune system due to exhausting exercise in intensively trained rats.Sci Rep. 2020 Jan 22;10(1):967. doi: 10.1038/s41598-020-57783-4. Sci Rep. 2020. PMID: 31969634 Free PMC article.
References
-
- Armstrong N., Mc Manus A. M. (2011). Preface. The elite young athlete. Med. Sport Sci. 56, 1–3. - PubMed
-
- Bakker N. A., Verschuuren E. A., Erasmus M. E. (2007). Epstein-Barr virus-DNA load monitoring late after lung transplantation: a surrogate marker of the degree of immunosuppression and a safe guide to reduce immunosuppression. Transplantation 83, 433–438. 10.1097/01.tp.0000252784.60159.96 - DOI - PubMed
LinkOut - more resources
Full Text Sources
Other Literature Sources
Research Materials