Exercise lipid metabolism

Costlll, D, L., Fink, W. J., Getchell, L. H., Ivy, J. L. and Wltzmann, F. A. (1979) Lipid metabolism In skeletal muscle of endurance trained males and females. J. Appl. Physiol. Resplrat, Environ. Exercise Physiol. 47 787-91. 

Koch G, Franz IW, Lohmann FW. Effects of short-term and long-term treatment with cardio-selective and non-selective beta-receptor blockade on carbohydrate and lipid metabolism and on plasma catecholamines at rest and during exercise. Clin Sci (Lond) 1981 61(Suppl 7) S433-5. 

Myophosphorylase deficiency is the classic example of a carbohydrate-related dynamic syndrome. Affected persons are unable to mobilize glycogen therefore they cannot perform high-intensity work and must rely extensively on lipid metabolism. Several other defects of glycolysis produce similar symptoms. All are characterized by inability to do anaerobic work and to produce lactate during ischemic exercise, which is the basis for the customary screening test for these disorders. Patients are asked to perform maximal hand grip contractions at the rate of one per second for 60 seconds with the forearm circulation... 

Horowitz, J. F-, and Klein, S. 2000, Lipid metabolism during endurance exercise. Am. J, Clin. Nulr. 72 558S 565S. 

Wu, J. J. Oka M. Higuchi I. Tabata T. Toda M. Fujioka N. Fuku T. Teramoto T. Okuhira T. Ueno, et al. Cooperative effects of isoflavones and exercise on bone and lipid metabolism in postmenopausal Japanese women A randomized placebo-controlled trial. Metabolism 2006, 55, 423-433. 

In conclusion, the majority of studies reveal that carnitine supplementation does not seem to provide an ergogenic benefit to human performance. The body and diet are sufficient to provide enough carnitine to allow an individual to effectively regulate lipid metabolism both at rest and dming various types of exercise. 

Glutaric aciduria type II, which is a defect of P-oxida-tion, may affect muscle exclusively or in conjunction with other tissues. Glutaric aciduria type II, also termed multiple acyl-CoA dehydrogenase deficiency (Fig. 42-2), usually causes respiratory distress, hypoglycemia, hyperammonemia, systemic carnitine deficiency, nonketotic metabolic acidosis in the neonatal period and death within the first week. A few patients with onset in childhood or adult life showed lipid-storage myopathy, with weakness or premature fatigue [4]. Short-chain acyl-CoA deficiency (Fig. 42-2) was described in one woman with proximal limb weakness and exercise intolerance. Muscle biopsy showed marked accumulation of lipid droplets. Although... 

With the non-invasive tool of muscular proton MR spectroscopy it is possible to study lipid oxidation, especially oxidation of IMCL, during exercise much more comfortably and precisely. Boesch et al revealed a decrease of IMCL in one subject performing a mountain bike ride over 3 h at about 70% of V02max, for the first time suggesting that IMCL are metabolized during this form of exercise. 

As discussed above, aerobic exercise produces numerous physiologic and metabolic changes in the body. Many of these changes are believed to be beneficial for prevention of heart disease. The effects on cardiopulmonary function were mentioned earlier and are clearly beneficial, as are the changes in body composition described in Chapter 9. Further, aerobic exercise appears to have positive effects on blood oholesterol and other lipids. These effects of exercise on the metabolism of lipids and the important transport particles called lipoproteins are discussed in Chapter 5. 

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