This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by White, L. J. Articles by Kim, H. Search for Related Content PubMed PubMed Citation Articles by White, L. J. Articles by Kim, H.

Intramyocellular Lipid Changes in Men and Women during Aerobic Exercise: A ¹H-Magnetic Resonance Spectroscopy Study

Departments of Exercise and Sport Sciences (L.J.W., M.A.F., S.C.M.) and Radiology (H.K.), University of Florida, Gainesville, Florida 32611; Veterans Administration Medical Center (H.K.), Gainesville, Florida 32608; and Clinical Development (M.A.F.), Medtronic Sofamor Danek, Memphis, Tennessee 38132

Address all correspondence and requests for reprints to: Lesley J. White, Ph.D., Department of Exercise and Sport Sciences, University of Florida, P.O. Box 118206, Gainesville, Florida 32611-8206. E-mail: lwhite{at}hhp.ufl.edu.

This study was designed to compare intramyocellular lipid (IMCL) changes during 60 min of submaximal exercise in men and women. Eighteen moderately active (18–38 yr) men (n = 9) and women (n = 9) were recruited. Maximum oxygen consumption (O₂max) and body composition were used to match subjects for aerobic fitness and body composition. Subjects performed cycle ergometry for 1 h at 65% of O₂max. Expired gases were collected throughout exercise to determine caloric expenditure and substrate use. Blood samples were collected before and after exercise to evaluate markers of lipid metabolism. Pre- and postexercise proton spectra were acquired from the vastus lateralis using a 3-T whole-body imaging system. Spectra were acquired from an 18-mm³ region of interest (echo time = 45 msec; repetition time = 2000 msec) for IMCL evaluation. IMCL decreased significantly with exercise (11.5–28.5% for men and 17.1–21.7% for women) (P < 0.05); however, there were no significant differences between men and women. Although changes were found for many plasma variables [free fatty acids, glycerol, and norepinephrine (P < 0.05)], group differences were only evident for norepinephrine. In conclusion, a significant decrease in IMCL was observed during 60 min of cycling in matched men and women.

This work was supported by a University of Florida opportunity grant.

Abbreviations: EMCL, Extramyocellular lipid; FFA, free fatty acid; FFM, fat-free mass; ¹H-MRS, proton nuclear magnetic resonance spectroscopy; HR, heart rate; HSL-A, adipose hormone-sensitive lipase; HSL-M, muscle hormone-sensitive lipase; IMCL, intramyocellular lipid; RER, respiratory exchange ratio; TG, triglyceride.

This article has been cited by other articles:

				K. J. Nadeau, P. S. Zeitler, T. A. Bauer, M. S. Brown, J. L. Dorosz, B. Draznin, J. E. B. Reusch, and J. G. Regensteiner Insulin Resistance in Adolescents with Type 2 Diabetes Is Associated with Impaired Exercise Capacity J. Clin. Endocrinol. Metab., October 1, 2009; 94(10): 3687 - 3695. [Abstract] [Full Text] [PDF]

				M. C. Devries, S. A. Lowther, A. W. Glover, M. J. Hamadeh, and M. A. Tarnopolsky IMCL area density, but not IMCL utilization, is higher in women during moderate-intensity endurance exercise, compared with men Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2007; 293(6): R2336 - R2342. [Abstract] [Full Text] [PDF]

				M.-H. Cui, J.-H. Hwang, V. Tomuta, Z. Dong, and D. T. Stein Cross contamination of intramyocellular lipid signals through loss of bulk magnetic susceptibility effect differences in human muscle using 1H-MRSI at 4 T J Appl Physiol, October 1, 2007; 103(4): 1290 - 1298. [Abstract] [Full Text] [PDF]

				T. Stellingwerff, H. Boon, R. A. M. Jonkers, J. M. Senden, L. L. Spriet, R. Koopman, and L. J. C. van Loon Significant intramyocellular lipid use during prolonged cycling in endurance-trained males as assessed by three different methodologies Am J Physiol Endocrinol Metab, June 1, 2007; 292(6): E1715 - E1723. [Abstract] [Full Text] [PDF]

				J S Volek, C E Forsythe, and W J Kraemer Nutritional aspects of women strength athletes Br. J. Sports Med., September 1, 2006; 40(9): 742 - 748. [Abstract] [Full Text] [PDF]

				Y. Tamura, Y. Tanaka, F. Sato, J. B. Choi, H. Watada, M. Niwa, J. Kinoshita, A. Ooka, N. Kumashiro, Y. Igarashi, et al. Effects of Diet and Exercise on Muscle and Liver Intracellular Lipid Contents and Insulin Sensitivity in Type 2 Diabetic Patients J. Clin. Endocrinol. Metab., June 1, 2005; 90(6): 3191 - 3196. [Abstract] [Full Text] [PDF]

				N. Rasouli, U. Raue, L. M. Miles, T. Lu, G. B. Di Gregorio, S. C. Elbein, and P. A. Kern Pioglitazone improves insulin sensitivity through reduction in muscle lipid and redistribution of lipid into adipose tissue Am J Physiol Endocrinol Metab, May 1, 2005; 288(5): E930 - E934. [Abstract] [Full Text] [PDF]

				L. J. C. van Loon Use of intramuscular triacylglycerol as a substrate source during exercise in humans J Appl Physiol, October 1, 2004; 97(4): 1170 - 1187. [Abstract] [Full Text] [PDF]