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Quem sou eu

São Paulo, São Paulo, Brazil
Professor da EEFE-USP; Praticante e Pesquisador de Judô; Preparador físico de atletas de modalidades esportivas de combate.

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segunda-feira, 20 de junho de 2011

Imunidade da mucosa e atividade antioxidante durante treinamento intensivo e perda de peso em atletas de TKD

Dica do Fabrício
Changes of mucosal immunity and antioxidation activity in elite male Taiwanese taekwondo athletes associated with intensive training and rapid weight loss

M-L Tsai1, K-M Chou1, C-K Chang2, S-H Fang1
1Institute of Athletics, National Taiwan Sport University, Taichung, Taiwan
2Sport Science Research Center, National Taiwan Sport University, Taichung, Taiwan

Objective The aim of this study was to investigate the cumulative effects of prolonged, intensive training and rapid weight loss on immunological parameters and antioxidation activity of elite male Taiwanese taekwondo athletes.
Design 16 Elite male taekwondo athletes (mean age, 21.6 (1.3) years; mean height, 173.7 (5.5) cm) volunteered to participate in this study. Beginning at 30 days before a national competition, saliva samples were obtained during a 7-week training, the competition and the postcompetition period. Levels of salivary IgA, cortisol, lactoferrin and free-radical scavenging activity were measured at 30-, 14-, 7- and 1-day precompetition and 1-, 7- and 19-day postcompetition. Body weight and body fat were also recorded.
Results The mean body weight was notably decreased during the week immediately before the competition. Results reveal that the levels of salivary IgA were differentially regulated during the training, competition and recovery period, while the salivary cortisol and lactoferrin concentrations and free-radical scavenging activity were not appreciably affected during the training and the competition period. Furthermore, the results of an upper respiratory tract infection incidence indicate that following the decreases of mucosal immunity, the risk of acquiring infection was significantly increased.
Conclusions Our results demonstrated that mucosal immunity in elite male taekwondo athletes is modulated by exercise and rapid weight reduction during the training, competition and recovery period. Cumulative effects of prolonged intensive training and rapid weight reduction suppressed mucosal immunity. Furthermore, because of the “open window” of impaired immunity during the precompetition period, the incidence of upper respiratory tract infection was significantly increased after the competition.

Tempo de reação em boxeadores

J Sports Med Phys Fitness. 2011 Jun;51(2):292-8.
Baseline simple and complex reaction times in female compared to male boxers.
Bianco M, Ferri M, Fabiano C, Giorgiano F, Tavella S, Manili U, Faina M, Palmieri V, Zeppilli P.
Sports Medicine Department, Catholic University, Rome, Italy - massimiliano.bianco@fastwebnet.it.
AIM: The aim of the study was to compare baseline cognitive performance of female in respect to male amateur boxers. METHODS. Study population included 28 female amateur boxers. Fifty-six male boxers, matched for age, employment and competitive level to female athletes, formed the control group. All boxers had no history of head concussions (except boxing). Each boxer was requested to: 1) fulfill a questionnaire collecting demographic data, level of education, occupational status, boxing record and number of head concussions during boxing; 2) undergo a baseline computerized neuropsychological (NP) test (CogSport) measuring simple and complex reaction times (RT).
RESULTS: Female were lighter than male boxers (56±7 vs. 73.1±9.8 kg, P<0.0001). No significant differences at CogSport scores were observed between groups. Male boxers showed a longer simple-RT at the end of the NP battery than at the beginning (0.247±0.007 vs. 0.243±0.007 s, P=0.02), however, with a significant lower rate of mistakes (0.7±1.6 vs. 2.0±3.1%, P=0.005), observed also in the female group (0.5±1.1 vs. 2.2±3.0%, P=0.005). No boxing activity parameter (record, number of knock-outs, etc.) correlated with NP scores.
CONCLUSION: Female and male Olympic-style boxers have no (or minimal) differences in baseline cognitive performance. Further research with larger series of female boxers is required to confirm these findings.