Discriminant Serum Biochemical Parameters in Top Class Marathon Performances.

Abstract

For male subjects, the difference within top-level marathon performances did not exceed 4% between the 20 best marks (2 h 05 min-2 h 10 min). The differences in the metabolic response to exercise are globally understood between sedentary and trained subjects [1,2], as well as between moderately trained and highly trained subjects [3][4][5][6]. For endurance sports, readily accessible parameters, i.e., maximal oxygen consumption (VO 2 max ), heart rate, lactatemia, glycogen stores depletion, or ammonia release, might be sufficient for this discrimination. Nevertheless, little is known about metabolic parameters that may discriminate between high-and top-level marathon performances. To our knowledge, the evolution of given metabolic parameters with a higher marathon performance level have not been reported for the best marathon runners.Lipids represent the most important fuel source during endurance exercise at moderate intensity. However, during an intense endurance exercise, such as a marathon performed over 75% of VO 2 max , circulating FFA cannot meet the oxidative needs, and intramuscular triglyceride (TG) stores must be used in large amounts [7]. It has ever been suggested that marathon performance level was mainly dependent on carbohydrate availability to skeletal muscle [8]. In an argument favoring this statement, it has been shown that endurance training improves muscle ability for oxidizing lactate and increases the membrane transport of lactate [9]. Intense exercise training also improves Japanese Journal of Physiology, 52, 181-190, 2002 Key words: FT-IR spectrometry, endurance, amino acids, long-chain fatty acids, protein catabolism.Abstract: Blood chemical parameters were analyzed by Fourier-transform infrared spectrometry (notably for determining the concentrations of glucose, lactate, urea, glycerol, triglycerides, and proteins) in 14 top-class marathon runners (133.7Ϯ4.1 min at marathon, 10.1% difference between extremes) who performed a 10-km run at their individual marathon velocity. Marathon performance level was correlated to glycemia increase during exercise (9% difference between extremes; rϭ0.93; pϽ0.005). The best marathon runners presented longer and/or less unsaturated blood fatty acids during exercise (17% difference between extremes; rϭ0.89; pϽ0.01), suggesting an improved fatty acid selectivity for muscular metabolism. The marathon performance level was also found correlated to a decrease of blood triglycerides during exercise (rϭϪ0.95; pϽ0.003) and to a proportional glycerol concentration increase (11% difference between extremes; rϭ0.94; pϽ0.005). The best marathon runners presented higher amino acid blood delivery (rϭ0.88; pϽ0.01), which was correlated to an apparent protein catabolism. These results show that the best runners have enhanced both carbohydrate, lipid, and amino acid metabolisms to improve energetic supply to skeletal muscle during exercise.

Fourier-Transform Infrared Spectrometry Determination of the Metabolic Changes During a Maximal 400-Meter Swimming Test

“…Indeed, this n as CH 2 /n as CH 3 ratio increase during exercise could be attributed to the release of long chain fatty acids from TG. This fatty acid selectivity [9] has been observed in other endurance sport specialists [15], and appears to be of major importance to provide more energetic substrates to skeletal muscles during exercise. Table 2 for details on molecular absorptions; n = 7 male swimmers.…”

Changes in thioredoxin concentrations: an observation in an ultra-marathon race

“…Most fat is stored as triglycerides in the subcutaneous and visceral fat tissues, and the latter are taken up by the skeletal muscle cells as FFA during exercise [20]. Plasma FFA subsequently become the major source of energy during exercise, indicating a reduction in plasma triglycerides.…”

Athletes with higher VO2max present reduced oxLDL after a marathon race

“…The practice of moderate exercise training is associated with increased high-density lipoprotein (HDL) and a reduction in low-density lipoprotein (LDL), total cholesterol and triacylglycerol (TAG) 710 Lipids are considered to be one of the most important fuel sources during moderate-intensity exercise 1112 After a session of prolonged and exhaustive exercise, such as observed in a marathon, there are significant changes in lipid profile, particularly the susceptibility of LDL cholesterol (LDL-C) to oxidation 8.…”