All the different stages of phagocytic function in blood polymorphonuclear neutrophils of sedentary (untrained) young men before, immediately after, and 15 min after being subjected to submaximal acute moderate exercise (50% maximal oxygen uptake) on a cycle ergometer were studied. No statistically significant differences were found in adherence or microbicide capacity against Candida albicans immediately after physical exercise. However, spontaneous mobility, chemotaxis and attachment and phagocytosis of Candida albicans at 15 min of incubation were significantly stimulated. Fifteen minutes after exercise spontaneous mobility, chemotaxis, and attachment of Candida albicans had returned to basal values, while phagocytosis of Candida albicans remained higher than basal values. One can, therefore, conclude that acute moderate exercise stimulates the phagocytic capacity of neutrophils in sedentary young men. In addition, no differences were found in the plasma adrenocorticotropic hormone concentration after exercise. However, immediately after exercise there was a decrease in the serum cortisol concentration, which had returned to basal 15 min later.

A study was made of all the different stages of the phagocytic function in peritoneal macrophages from male guinea pigs [3 (SD 1) months old] before, immediately after, and 24 h after being subjected to stress from physical activity (swimming until exhaustion). The early (10 min) and late (40 min) adherence to tissue substrates, chemotaxis, attachment and phagocytosis of Candida albicans, ingestion of inert particles (latex beads), and basal oxidative metabolism [measured by nitroblue tetrazolium (NBT) reduction] were significantly stimulated by the physical activity. After 24 h, late adherence, attachment capacities, and basal oxidative metabolism returned to basal values, whereas early adherence, chemotaxis, phagocytosis of cells and inert particles, and microbicidal capacity (production of superoxide anion measured by NBT reduction in presence of ingested material) remained significantly increased. The stress produced by physical activity, reflected in increased serum corticosterone values, led to a global stimulation of the phagocytic function.

No abstract

No abstract

The influence of a single session of moderate exercise (45 min at 55% of VO(2 )max) performed by young sedentary men (23-25 years old) on the microbicidal capacity of neutrophils was compared by using both direct (killing of phagocytosed Candida albicans) and indirect (superoxide anion production measured by NBT reduction) techniques. In addition, the role of norepinephrine and heat shock protein (Hsp) 72 in the modulation of microbicide capacity of neutrophils was evaluated during the protocol of exercise and recovery period (24 h). No significant changes were found in the superoxide production after exercise. However, immediately after exercise there was an increase in the destruction of C. albicans, which remained higher than basal values 1 day later. This behaviour was similar to the changes found in the serum extracellular Hsp72 concentrations (an increase after exercise that remained higher than basal values 24 h later). In vitro, the raised physiological concentration of Hsp72 after exercise also increased the microbicide capacity of neutrophils with respect to controls and the values induced by the basal concentration of the protein. This indicates that Hsp72 is participating as a "stress mediator" of the stimulated microbicide activity during moderate exercise. However, norepinephrine is not mediating the increased killing of C. albicans during exercise.