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DOI: 10.1055/s-2007-1024917
Influence of Polyunsaturated Fatty Acid Diet on the Hemorrheological Response to Physical Exercise in Hypoxia*
* This study was supported by grant DRET No. 87/1076 from the French Ministry of DefensePublication History
Publication Date:
14 March 2008 (online)
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 MaxEPAfish 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 V̇O2max. One test was performed at sea level, the other at a simulated altitude of 3000 m in a hypobaric chamber. Blood samples were drawn before and after exercise and used to evaluate: (1) RCD by filtration on polycarbonate membrane, (2) plasma viscosity, and (3) erythrocyte phospholipid composition. Energy charge of red cell was eva-luted by ATP/AMP/ADP and two to three DPB assays. Gas liquid chromatography indicated an increase in n-3 PUFA membrane erythrocyte 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 offish oil supplement.
Key words
polyunsaturated fatty acid - red cell deformability - hypoxia - physical exercise