Autor(es):
Valado, Ana 
; Tavares, Paula C. ; Pereira, Leonel ; Ribeiro, C. Fontes
Data: 2007
Identificador Persistente: http://hdl.handle.net/10316/14452
Origem: Estudo Geral - Universidade de Coimbra
Assunto(s): oxidative stress; Anaerobic exercise
Descrição
The physical exercise is considered beneficial contributing for physical, psychological and social
wellbeing and balance of the individual, being able to delay the aging process. The physical exercise unchains a
physiological stress situation, to which, the sympathetic nervous system activity answers activating adaptation
mechanisms. The availability of oxygen and the nitric oxide release, provide the formation of reactive oxygen
species (ROS), related with the origin of cellular and tissue injuries. In order to evaluate the effect of the
exercise we selected a set of sixteen healthy young individuals, voluntary, that they had constituted two distinct
groups: the athlete, constituted by futsal athlete; and the control group, formed for individuals that did not
practise any type of sport with regularity. The main objective of this work was to investigate if the acute and
intense exercise originates, in both the groups, in the production and release of NO and in the production of free
oxygen radicals. With this purpose the Wingate test is used (supramaximum anaerobic test executed in 30
seconds). After that, the concentrations of blood lactate, platelet and plasmatic nitric oxide and the plasmatic
malondialdehyde (MDA) had been determined. All the determination had been made in two blood samples: one
harvested before the exercise and the other 15 minutes after the Wingate test; with the exception of lactates,
which was executed 5 minutes after the test. The innovation of the present study showed in the plasmatic
malondialdehyde levels, which revealed in the athletes a significant reduction, in rest and after exercise,
relatively to the control group. A significant reduction in the blood lactate concentration was verified in the
athletes, after exercise, in relation to the control. On the other hand, the concentrations of total intra-platelet
nitrites and released for the platelet, presented in the athletes a significant increase, in rest and after exercise,
relatively to the control. The differences are related with the physical training, seeming to stimulate the
adaptation mechanisms and the antioxidation defences of the athletes, conferring bigger cardiovascular
protection and enhanced protection against physical and oxidative stress, comparatively to the individuals that
did not practise sport with regularity. Thus, in young individuals, seems to us that the regular physical activity
and the intense exercise develop a physiological adaptation, such that, after a maximum acute exercise, has
pointers of an enhanced cardiovascular protection and against oxidative stress.
