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1.
Scand J Med Sci Sports ; 27(9): 925-934, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27367601

RESUMO

Elite synchronized swimmers follow high-volume training regimen that result in elevated rates of exercise energy expenditure (ExEE). While adequate energy intake (EI) is important to optimize recovery, a number of sport-specific constraints may lead to chronically low energy availability (EA = EI-ExEE). This study aimed to quantify changes in EA, endocrine markers of energy conservation, and perceived fatigue in synchronized swimmers, during a week of baseline training followed by 4 weeks of intensified training (IT). EI, ExEE, and body composition were measured in nine swimmers at Baseline, midpoint (ITWK2 ), and end of IT (ITWK4 ). Waking saliva samples were obtained to measure [leptin]s , [ghrelin]s , and [cortisol]s . Fatigue ratings were provided daily. ExEE increased by 27% during IT. Swimmers increased EI from Baseline to ITWK2 , but decreased it significantly from ITWK2 to ITWK4 . EA, fat mass, and [leptin]s decreased from Baseline to ITWK4 , while [ghrelin]s increased significantly. Fatigue at ITWK4 was inversely correlated with Baseline EI and EA. The significant decrease in EA was accompanied by endocrine signs of energy conservation in elite swimmers. As perceived fatigue was associated with low EA, particular attention should be paid to these athletes' energy intake during phases of heavy training.


Assuntos
Ingestão de Energia , Metabolismo Energético , Fadiga/fisiopatologia , Natação/fisiologia , Atletas , Composição Corporal , Feminino , Grelina/análise , Humanos , Hidrocortisona/análise , Leptina/análise , Condicionamento Físico Humano , Saliva/química , Adulto Jovem
2.
Eur J Appl Physiol ; 94(3): 298-304, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15765238

RESUMO

Secretory immunoglobulin A (sIgA) is the major immunoglobulin of the mucosal immune system. Whereas the suppressive effect of heavy training on mucosal immunity is well documented, little is known regarding the influence of hypoxia exposure on sIgA during altitude training. This investigation examined the impact of an 18-day Living high-training low (LHTL) training camp on sIgA levels in 11 (six females and five males) elite cross-country skiers. Subjects from the control group (n=5) trained and lived at 1,200 m of altitude, whereas, subjects from the LHTL group (n=6) trained at 1,200 m, but lived at a simulated altitude of 2,500, 3,000 and 3,500 m (3x6-day, 11 h day(-1)) in hypoxic rooms. Saliva samples were collected before, after each 6-day phases and 2 weeks thereafter (POST). Salivary sIgA, protein and cortisol were measured. There was a downward trend in sIgA concentrations over the study, which reached significance in LHTL (P<0.01), but not in control (P=0.08). Salivary IgA concentrations were still lower baseline at POST (P<0.05). Protein concentration increased in LHTL (P<0.05) and was negatively correlated with sIgA concentration after the 3,000 and 3,500 m-phase and at POST (P<0.05 all). Cortisol concentrations were unchanged over the study and no relationship was found between cortisol and sIgA. In summary, data were strongly suggestive of a cumulative negative effect of physical exercise and hypoxia on sIgA levels during LHTL training. Two weeks of active recovery did not allow for proper sIgA recovery. The mechanism underlying this depression of sIgA could be mediated by neural factors.


Assuntos
Altitude , Imunidade/fisiologia , Mucosa Bucal/imunologia , Educação Física e Treinamento , Características de Residência , Adulto , Feminino , Humanos , Hidrocortisona/metabolismo , Imunoglobulina A/metabolismo , Masculino , Concentração Osmolar , Saliva/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Esqui
3.
Eur J Appl Physiol ; 93(4): 421-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15490219

RESUMO

This investigation examined the impact of a multistressor situation on salivary immunoglobulin A (sIgA) levels, and incidence of upper respiratory tract infection (URTI) during the French commando training (3 weeks of training followed by a 5-day combat course). For the URTI, the types of symptoms were classified according to the anatomical location of the infection. Saliva samples were collected (8 a.m.) from 21 males [21 (2) years] before entry into the commando training, the morning following the 3 weeks of training, after the 5-day combat course, and after 1 week of recovery. sIgA, protein and cortisol concentrations were measured. Symptoms of URTI were recorded during the study from health logs and medical examinations. After the 3 weeks of training, the sIgA concentration was not changed, although it was reduced after the 5-day course [from 120 (14) mg l(-1) to 71 (9) mg l(-1), P<0.01]. It returned to pre-training levels within a week of recovery. The incidence of URTI increased during the trial (chi(2)=53.48; P<0.01), but was not related to sIgA. Among the 30 episodes of URTI reported, there were 12 rhino-pharyngitis, 6 bronchitis, 5 tonsillitis, 4 sinusitis and 3 otitis. Cortisol levels were raised after the 3-week training (P<0.01), dropping below baseline after the combat course (P<0.01). Stressful situations have an adverse effect on mucosal immunity and incidence of URTI. However, the relationship between sIgA and illness remained unclear. The large proportion of rhino-pharyngitis indicated that the nasopharyngeal cavity is at a higher risk of infection.


Assuntos
Tolerância ao Exercício/imunologia , Imunoglobulina A/imunologia , Militares/estatística & dados numéricos , Mucosa Bucal/imunologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/imunologia , Saliva/imunologia , Estresse Fisiológico/imunologia , Adaptação Fisiológica/imunologia , Adulto , Exercício Físico , França/epidemiologia , Humanos , Incidência , Masculino , Esforço Físico
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