O impacto da hidratação sobre a contagem de células sanguíneas em ciclistas submetidos a exercício

Abstract

Physical exercise can benefit health and the immune system. The immune system is a defense system, which protects our body against invading microorganisms. The hydration status of the individual is essential for the practice of physical activities, and to prevent health problems. An individual dehydrated and in high physical stress, seems to generate a greater disturbance in the function of immune cells. Objective: to verify the impact of hydration on the leukocyte count and subpopulations in prolonged physical exercise, until exhaustion. Methods: The study consisted of 16 athlete cyclists (38.7 ± 14.6 years; 70.3 ± 5.5 kg; 170.6 ± 5.5 cm; 10.2 ± 4.3% G), from male. Cyclists performed a 30-minute exercise session on a cycle ergometer, followed by a maximum incremental test (TIM), in an air-conditioned room at ~ 25 oC. Blood was collected before the exercise session (moment 0; M0), after 30 minutes of the exercise session (moment 1; M1) and immediately after the maximum effort (moment 2; M2). Results: A significant difference in leukocyte count was observed between M0 (5.8 ± 0.5 x 103/ mm3) and M1 (8.8 ± 0.8 x 103 / mm3), and M0 (5.8 ± 0 , 5 x 103 / mm3) and M2 (9.8 ± 0.7 x 103 / mm3) within the most dehydrated group (+ DES) (P <0.05). In the less dehydrated group (–DES) there was only a difference between M0 (6.8 ± 0.5 x 103 / mm3) and M1 (8.8 ± 0.9 x 103 / mm3) (P <0.05). There was a significant difference in granulocytes between M0 (1.6 ± 0.3 x 103 / mm3) and M1 (2.4 ± 0.5 x 103 / mm3), and between M0 (1.6 ± 0.3 x 103 / mm3) and M2 (2.7 ± 0.5 x 103 / mm3) in the + DES group. In the lymphocytes there was an increase and a significant difference between M0 and M1 and between M0 and M2 (+ DES) (P <0.05). In the group (–DES) there was a significant difference between M0 and M1. And monocytes had an increase, and a significant difference between M0 and M1, M0 and M2, M1 and M2 (+ DES) (P<0.05). In the group (-DES) there was a significant difference between M0 and M1, M0 and M2 (P <0.05). Conclusion: Prolonged exercise, until exhaustion, induces a more marked increase in the number of circulating leukocytes and subpopulations at the highest level of dehydration.