title: Immune cell changes in response to a swimming training session during a 24-h recovery period.
abstract: Understanding the impact of training sessions on the immune response is crucial for the adequate periodization of training, to prevent both a negative influence on health and a performance impairment of the athlete. This study evaluated acute systemic immune cell changes in response to an actual swimming session, during a 24-h recovery period, controlling for sex, menstrual cycle phases, maturity, and age group. Competitive swimmers (30 females, 15 ± 1.3 years old; and 35 males, 16.5 ± 2.1 years old) performed a high-intensity training session. Blood samples were collected before, immediately after, 2 h after, and 24 h after exercise. Standard procedures for the assessment of leukogram by automated counting (Coulter LH 750, Beckman) and lymphocytes subsets by flow cytometry (FACS Calibur BD, Biosciences) were used. Subjects were grouped according to competitive age groups and pubertal Tanner stages. Menstrual cycle phase was monitored. The training session induced neutrophilia, lymphopenia, and a low eosinophil count, lasting for at least 2 h, independent of sex and maturity. At 24 h postexercise, the acquired immunity of juniors (15-17 years old), expressed by total lymphocytes and total T lymphocytes (CD3(+)), was not fully recovered. This should be accounted for when planning a weekly training program. The observed lymphopenia suggests a lower immune surveillance at the end of the session that may depress the immunity of athletes, highlighting the need for extra care when athletes are exposed to aggressive environmental agents such as swimming pools.
authors.affiliation: a Laboratory of Physiology and Biochemistry of Exercise, Faculty of Human Kinetics, University of Lisbon, Portugal.|b Interdisciplinary Center for Human Performance Study (CIPER), Faculty of Human Kinetics, University of Lisbon, Portugal.
authors.forename: José P
authors.initials: JP
authors.lastname: Morgado
authors.affiliation: a Laboratory of Physiology and Biochemistry of Exercise, Faculty of Human Kinetics, University of Lisbon, Portugal.|b Interdisciplinary Center for Human Performance Study (CIPER), Faculty of Human Kinetics, University of Lisbon, Portugal.
authors.forename: Cristina P
authors.initials: CP
authors.lastname: Monteiro
authors.affiliation: b Interdisciplinary Center for Human Performance Study (CIPER), Faculty of Human Kinetics, University of Lisbon, Portugal.
authors.forename: Júlia
authors.initials: J
authors.lastname: Teles
authors.affiliation: b Interdisciplinary Center for Human Performance Study (CIPER), Faculty of Human Kinetics, University of Lisbon, Portugal.|c Escola de turismo, desporto e hospitalidade, Universidade Europeia, Lisbon, Portugal.
authors.forename: Joana F
authors.initials: JF
authors.lastname: Reis
authors.affiliation: a Laboratory of Physiology and Biochemistry of Exercise, Faculty of Human Kinetics, University of Lisbon, Portugal.|b Interdisciplinary Center for Human Performance Study (CIPER), Faculty of Human Kinetics, University of Lisbon, Portugal.
authors.forename: Catarina
authors.initials: C
authors.lastname: Matias
authors.affiliation: d Department of Health Promotion and Prevention of non-Communicable Diseases, National Health Institute Doutor Ricardo Jorge (INSA), Lisbon, Portugal.
authors.forename: Maria T
authors.initials: MT
authors.lastname: Seixas
authors.affiliation: d Department of Health Promotion and Prevention of non-Communicable Diseases, National Health Institute Doutor Ricardo Jorge (INSA), Lisbon, Portugal.
authors.forename: Marta G
authors.initials: MG
authors.lastname: Alvim
authors.affiliation: d Department of Health Promotion and Prevention of non-Communicable Diseases, National Health Institute Doutor Ricardo Jorge (INSA), Lisbon, Portugal.
authors.forename: Mafalda
authors.initials: M
authors.lastname: Bourbon
authors.affiliation: c Escola de turismo, desporto e hospitalidade, Universidade Europeia, Lisbon, Portugal.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Laires
authors.affiliation: a Laboratory of Physiology and Biochemistry of Exercise, Faculty of Human Kinetics, University of Lisbon, Portugal.|b Interdisciplinary Center for Human Performance Study (CIPER), Faculty of Human Kinetics, University of Lisbon, Portugal.
authors.forename: Francisco
authors.initials: F
authors.lastname: Alves
mesh_terms: D056704:Adaptive Immunity / Q000502:physiology*; D000293:Adolescent; D056352:Athletes; D001823:Body Composition; D004804:Eosinophils / Q000166:cytology; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D016131:Lymphocyte Subsets / Q000166:cytology*; D008231:Lymphopenia; D008297:Male; D013550:Swimming / Q000502:physiology*
keywords: cellular immunity; immunité cellulaire; leucocytes; leukocytes; lymphocytes subsets; nageurs; recovery; récupération; sous-population de lymphocytes; swimmers; séance d’entraînement; training session