Abstract

Several studies have shown that hemorrheological parameters are modified by physical exercise and exposure to altitude hypoxia. These changes result in a decrease in red cell deformability (RCD). Similarly, it has been shown that a daily dietary fish oil supplement increases RCD. The purpose of this study was to evaluate the influence of fish oil diet on RCD after exercise. Fourteen male subjects (19-38 years old) were divided into two groups. The first group ate a standard diet rich in saturated lipids; the second group received a daily amount of 6 g of MaxEPA fish oil for 6 weeks. Before the 6 weeks of experimental nutrition, and just after this period, both groups were submitted to two physical exercises of 1 h cycling at 70 of their VO2max. One test was performed at sea level, the other at a simulated altitude of 3000 m in a hypobaric chamber. Blood samples were used to evaluate: (1) RCD by filtration on polycarbonate membrane, (2) plasma viscosity, and (3) erythrocyte phospholipid composition. In the control group, RCD decreased by an average of 53 after exercise under hypoxic conditions and was unchanged after the same exercise at sea level. MaxEPA diet suppresses the decrease in RCD observed after hypoxic exercise. These results indicate a decrease in RCD under the combined effects of exercise and hypoxia, which is prevented by 6 weeks of fish oil supplement. Verf.-Referat