Abstract
A few studies have been made in vivo on human myocardial energy metabolism. Hence, no discussion has taken place on metabolism during exercise or of training effects on metabolism. We examined human myocardial energy metabolism at rest and during exercise, and also training effects on the metabolism by phosphorus-31 nuclear magnetic resonance (31P NMR)-spectroscopy. Six sedentary male students (Cont) and six male long distance runners (Tr) were the subjects. Energy metabolism data were obtained from myocardium during rest and exercise by the region selection method using 31P NMR. Rotation of the legs while riding a bicycle, which was fitted with an ergometer we had made ourselves for NMR, imposed given exercise intensities. The heart rate was measured in a stationary phase during exercise. Although the heart rate at rest in the Tr group was significantly lower [Tr, 52.5 (SD 3.1) beat · min−1; Cont, 67.1 (SD 2.9) beat · min−1], no significant difference was observed in myocardial energy metabolism using the 31P NMR method [Tr, phosphocreatine/β-adenosine 5′-triphosphate (PCr/β-ATP); 1.51 (SD 0.02); Cont, 1.51 (SD 0.01)]. When NMR measurements were investigated at two different intensities of exercise, heart rates in the Cont group were significantly higher by about 20 beat · min −1 than those in the Tr group at both exercise intensities, while no difference in energy metabolism was observed between the groups or between rest and exercise [Tr, 75.9 (SD 3.6), 88.3 (SD 3.7) beat · min−; PCr/β-ATP 1.51 (SD 0.03), 1.51 (SD 0.03); Cont, 95.9 (SD 2.4), 115.1 (SD 3.5) beat · min−1 PCr/β-ATP 1.51 (SD 0.01), 1.51 (SD 0.04)]. Thus, during submaximal exercise as employed in this study, it would seem that the high energy phosphate level normally observed during rest may still be maintained. From these results, the absence of change in the myocardial PCr: ATP ratio suggested that adenosine 5′-diphosphate was not the primary regular of the increased metabolism needed to meet the higher cardiac workload during aerobic exercise in either group.
Similar content being viewed by others
References
Balaban RS, Kantor HL, Katz LA, Briggs RW (1986) Relationship between work and phosphate metabolite in the in vivo paced mammalian heart. Science 232:1121–1123
Blackledge MJ, Rajagopalan B, Oberhaensli RD, Bolas NM, Styles P, Radda GK (1987) Quantitative studies of human cardiac metabolism by 31P rotating-frame NMR. Proc Natl Acad Sci USA 84:4283–4287
Bottomely PA (1985) Noninvasive study of high energy phosphate metabolism in human heart by depth-resolved 31P NMR spectroscopy. Science 229:769–772
Bottomely PA, Herfkens RJ, Smith LS, Brazzamano S, Brinder R, Hedrund LW, Swain JL, Redington RW (1985) Noninvasive detection and monitoring of regional myocardial ischemia in situ using depth-resolved 31P NMR spetroscopy. Proc Natl Acad Sci USA 82:8747–8751
Chance B, Eleff S, Leigh J, Sokolow D, Sapega A (1981) Mitochondrial regulation of phosphocreatine/inorganic phosphate ratios in exercising human muscle; a gated 31P NMR study. Proc Natl Acad Sci USA 78:6714–6718
Chance B, Leigh JS, Kent J, McCully K (1986) Metabolic control principles and 31P NMR. Fed Proc 45:2915–2920
Conway MA, Bristow JD, Blackledge MJ, Rajagopalan B, Radda GK (1988) Cardiac metabolism during exercise measured by magnetic resonance spectroscopy. Lancet II:692
Flaherty JT, Weisfeldt ML, Bulkley BH, Gardner TJ, Gott VL, Jacobus WE (1982) Mecanisms of ischemic myocardial cell damage assessed by phosphorus-31 nuclear magnetic resonance. Circulation 65:561–570
Gollnick PD (1986) Metabolic regulation in skeletal muscle: influence of endurance training as exerted by mitochondrial protein concentration. Acta Physiol Scand 128 [Suppl 556]:53–66
Jacobus WE, Taylor GJ, Hollis DP, Nunnally RL (1977) Phosphorus nuclear magnetic resonance of perfused working rat hearts. Nature 265:756–758
Kuno S, Katsuta S, Akisada M, Mitsumori F (1990) Evaluation of exercise muscle energetics by MNR. Ann Physiol Anthropol 9:235–239
Kuno S, Akisada M, Anno I, Niitsu M, Itai Y, Katsuta S (1991) Heterogeneity of muscle energetics in human muscle fiber type using 31P NMR. Clin J Sport Med 1:247–250
Kuno S, Akisada M, Mitsumori F (1992) Phosphorus-31 nuclear magnetic resonance study on the effects of endurance training in rat skeletal muscle. Eur J Appl Physiol 65:197–201
Nunnally RL, Bottomely PA (1981) Assesment of pharmacological treatment of myocardial infarction by phosphorus 31 NMR with surfacecoil. Science 211:177–180
Robitaille P, Lew B, Merkle H (1989) Transmural metabolite distribution in regional myocardial ischemia as studied by 31P NMR. Magn Reson Med 10:108–118
Schaefer S, Camacho SA, Gober J (1989) Response of myocardial metabolites to graded regional ischemia: 31P NMR spectroscopy of porcine myocardium in vivo. Circ Res 64:968–976
Taylor DJ, Bore PJ, Styles P, Gadian DG, Radda GK (1983) Bioenergetics of intact human muscle. A 31P nuclear magnetic resonance study. Mol Biol Med 1:77–94
Weiss RG, Bottomely PA, Hardy CJ, Gerstenblith G (1990) Regional myocardial metabolism of high-energy phosphates during isometric exercise in patients with coronary artery disease. New Eng J Med 323:1593–1600
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kuno, Sy., Ogawa, T., Katsuta, S. et al. In vivo human myocardial metabolism during aerobic exercise by phosphorus-31 nuclear magnetic resonance spectroscopy. Eur J Appl Physiol 69, 488–491 (1994). https://doi.org/10.1007/BF00239864
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00239864