Efeitos agudos do exercÃcio resistido sobre linfÃcitos totais, CD4 e CD8 de idosas

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

Introduction - Physical exercise has been recommended to minimize the effects of the aging process and resistance training has been recognized as a type of exercise efficient in increase muscle strength and mass of older individuals. On the other hand, high intensity exercise is associated with a higher incidence of illness in athletes, particularly those of infectious etiology. Quantify the adequate workload to elderly people became a challenger task, since it acute variable affects all organic systems, especially the possibly blunted immune system, fact that would increase the risk of illness in this population. Objectives â The aim of this study was to investigate and compare the immediate and delayed acute effects of different resistance exercise intensities (50 and 80% of 1-RM) on total lymphocytes, CD4+, CD8+ and CD4+/CD8+ ratio of older women. Materials and Methods â 15 older women (67,53Â3,92 years old) were recruited on a voluntary basis to participate of this study who randomly performed three exercise sessions as follows: In S1 they performed two sets of 13 repetitions at 50% of 1-RM; in S2 two sets of eight repetitions at 80% of 1-RM; and ST was the control session. The intervals between sets were 1â20ââ, the execution speed was in average 6 seconds (eccentric plus concentric), and the sessions were separated for one week. For evaluation of dynamic strength one maximum repetition (1-RM) test was used. Blood samples to measure total lymphocytes, CD4+, CD8+ and CD4+/CD8+ ratio were collected pre-exercise (T1), immediately after (T2), as well as three (T3) and 48 hours after exercise (T4). The citometry flow was used to quantify the immune cells from 15ml of blood samples collected in EDTA tubes, witch were stored with 5 ml of monoclonal antibodies [CF - Anti-CD4, conjugated with FITC (isotiocianate of fluoresceine 032) and CF 035 - Anti-CD8, conjugated with FITC]. The analyses were performed in a CELL-DYN 3500 instrument. For statistics analysis, the Kolmogorov Smirnov and Skewness tests were used to verify the data distribution and analysis of variance (Two way ANOVA) for repeated measures was used to examine yhe effects of resistance exercises. The significance level was accepted at P ≤ 0,05. Results â In relation to total lymphocytes, it was observed significant differences between all the moments (T1, T2, T3 and T4), however, such difference was not observed between the exercise sessions. In relation to the CD4+ cells, it was observed significant differences between the moments, although such result was only observed in the exercise session performed at 80% of 1-RM (S1) and in the control session (ST). Significant differences (p≤0,05) in the CD8+ cells counting were observed between T3 and T4 in the exercise session performed at 80% of 1-RM (S1), and between T1 and T3, and T3 and T4 in the control session (ST). The CD4+/CD8+ ratio didnât present significant differences between the moments for none of the sessions performed. Conclusions â Resistance exercise performed at the intensity of 50% or 80% of 1-RM didnât induce, as an acute response, alterations in the elderly organism that configure an immune-depression process mediated by the exercise.

ASSUNTO(S)

sistema imunolÃgico e linfÃcitos envelhecimento aging exercÃcio resistido educacao fisica immune system lymphocytes resistance exercise

ACESSO AO ARTIGO

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