Immunological Status of Competitive Cyclists Before and After the Training Season

Abstract

The total number of leucocytes, T lymphocyte subsets, mitogen induced proliferation of lymphocytes, Il-2 generation, adherence capacity and chemiluminescence of granulocytes were measured and a leukergy test performed in fifteen young cyclists. The investigations were carried out at rest at the beginning of a training season and after six months of intensive training and a racing season, cycling approximately 500 km a week. Baseline values of the tested immune parameters were within the range observed in 16 non-trained healthy controls except significantly increased non stimulated neutrophil chemiluminescence. The second cyclo-ergometer test in August showed a marked improvement in the performance capacity of the cyclists. Significant decrease in absolute numbers of CD3⁺ and CD4⁺ cells, diminished IL-2 generation and fMLP and PMA stimulated chemiluminescence of neutrophils were noted. Surprisingly, a marked increase in lymphocyte proliferation induced by PHA and anti-CD3 MoAb and normalisation in non stimulated neutrophil chemiluminescence were also observed at rest after the training season. We conclude that long-lasting intensive training may result in significant alterations in lymphocyte number and composition and in neutrophil oxidative burst capacity, but their actual significance for immunity is seen controversially.

Key words

Effort - immune system - neutrophile function - adaptation