Clinical trial NCT00946855: Effect of Elite Soccer Training on Routine Laboratory Parameters
Official title: Laboratory Values in Elite Soccer Players
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Stress
Keywords: soccer
laboratory
reference
exercise
variability
season
elite athletes
Define reference blood parameters in elite athletes
Lead sponsor: Universität des Saarlandes
Sponsor class: OTHER
First posted: 2009-07-27
Enrollment: 467
Sex: MALE
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: soccer players of the first two German professional soccer leagues

Brief summary: Repeated blood sampling within a regular soccer season of German first league clubs shall serve to define soccer-specific reference values for routine parameters determined from venous blood. It was hypothesized that only for a minor number of parameters common reference values will have to be adapted for soccer players during their competitive season.

Detailed description: It is often difficult to discern exercise-induced changes in laboratory parameters from pathological changes in elite athletes during the regular training process. This is particularly true in soccer players who compete more often than many other athletes. Therefore, soccer players of the first two German soccer leagues (all professional athletes) are recruited for repeated blood sampling during the season (4 sampling times, one of them immediately before training commences in the summer, the other ones in October/November, February/March, and April/May). Among other standardizing requirements, it is mandatory that precisely one training session (not zero, not two, no competition) takes place the day before sampling. Several confounders for the interpretation of laboratory results are verified by means of a questionnaire. Phases of high competitive stress are compared with those of low stress. The course of the parameters as well as confidence intervals for given times during the season are of main interest.

Eligibility criteria: Inclusion Criteria:

* being employed as player by a club of the first two German soccer leagues
* healthy

Exclusion Criteria:

* chronic disease interfering with one or more of the determined parameters

Primary outcomes:
measure: complete blood count
timeFrame: August 2008 until May 2009
Secondary outcomes:
measure: numerous serum parameters from venous blood
timeFrame: August 2008 until May 2009
Other outcomes:
Locations:
city: Saarbrücken
country: Germany
facility: Institute of Sports and Preventive Medicine, University of Saarland, Campus, Bldg. B 8-2,
state: Saarland
Study officials:
affiliation: Institute of Sports and Preventive Medicine, University of Saarland, Campus, Bldg. B 8-2, 66123 Saarbrücken, Germany
name: Tim Meyer, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Breitbart P, Meister S, Meyer T, Gartner BC. Incidence and Prevalence of Borrelia burgdorferi Antibodies in Male Professional Football Players. Clin J Sport Med. 2021 Jul 1;31(4):e200-e206. doi: 10.1097/JSM.0000000000000758.
citation: Meyer T, Meister S. Routine blood parameters in elite soccer players. Int J Sports Med. 2011 Nov;32(11):875-81. doi: 10.1055/s-0031-1280776. Epub 2011 Oct 21.