Effects of training on lipid metabolism in swimming muscles of sea trout (Salmo trutta).
We examined the effect of exercise intensity and endurance training on plasma free fatty acid (FFA) kinetics and lipid metabolism in swimming muscles of reared sea trout. In both training groups [water current velocities 1 and 2 body lengths per second (bl s(-1))] the plasma level of FFAs decreased significantly (P < 0.001) compared to the control group. Similar significant (P < 0.01) post-exercise decrease was observed also in the lipase-esterase activity in the red muscle, but not in white. Moreover, in the group swimming with higher intensity a significantly higher (P < 0.05) lipase-esterase activity in the red muscle was found compared with the group on moderate exercise. As with cytochrome c oxidase activity, a significant elevation in the enzyme activity was also observed after training in the 1 bl s(-1) group in red and white muscle (P < 0.05 and P < 0.01, respectively). No changes were observed in beta hydroxyacyl CoA dehydrogenase activity. The lipid content was on average nine times higher in red compared to white muscle being 16.7, 21.1, and 24.9% in the red muscle of the control, 1 and 2 bl s(-1) groups, respectively, with a significant (P < 0.05) increase after training. We conclude that (1) unlike in mammals, plasma FFA kinetics and oxidation are not linearly related to exercise intensity in reared sea trout, (2) training enhances the capacity to uptake FFA from plasma, and (3) high intensity training shifts the proportion of energy derived from fat oxidation to carbohydrate-derived energy.
Anttila
Katja
K
Department of Biology, University of Oulu, PO Box 3000, 90014 Oulu, Finland.
Jäntti
Maria
M
Mänttäri
Satu
S
D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000097:blood; D000818:Animals; D003576:Electron Transport Complex IV / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D008049:Lipase / Q000378:metabolism; D050356:Lipid Metabolism / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology; D010805:Physical Conditioning, Animal; D010807:Physical Endurance / Q000502:physiology; D013550:Swimming / Q000502:physiology*; D014337:Trout / Q000502:physiology*
D005230:Fatty Acids, Nonesterified; D015094:3-Hydroxyacyl CoA Dehydrogenases; D003576:Electron Transport Complex IV; D008049:Lipase