Acute effect of the maximal cardiorespiratory capacity test on the levels of leukocytes, neutrophils, NK, B and T cells in soccer players

Performance of maximal cardiorespiratory capacity (V̇O2max) tests is common in intermittent aerobic sports such as soccer. V̇O2max test is considered a strenuous exercise, which can modulate immunity. Thus, it is necessary to understand how immunological indicators react after performing a V̇O2max test. We aimed to analyze the acute effect of the V̇O2max test on immunological indicators in football athletes. Pre-experimental trial with a sample of 16 college soccer athletes (male gender, age: 22.0±1.7). The athletes underwent V̇O2max test performed on a mechanical treadmill; respiratory gas analysis occurred by ergoespirometry. Blood samples (20mL) were collected from the athletes at the pre and post V̇O2max test moments. Immunological indicators were determined by complete blood count tests for total leukocyte count and subtypes (lymphocytes, NK-cells and neutrophils) and immunophenotyping (T/B-lymphocytes) by flow cytometry. After V̇O2max testing, there was a significant increase in total leukocyte (Effect-size: 3.4, p: 0.001) and lymphocyte (Effect-size: 3.1, p: 0.001) counts, and a decrease in the percentage of neutrophils (Effect-size: 1.1, p<0.001). There was an increase in T lymphocyte subpopulations: CD3-CD16-56, CD16-56, CD56, CD3, CD3-CD4, CD3-CD8 (Effect-size>0.6, p<0.05), as well as an increase in CD-20 B-lymphocytes (Effect size: 0.6). In soccer athletes, the V̇O2max test promotes increased levels of total leukocytes and lymphocytes, as well as, promotes reduced levels of neutrophils.