Author/Authors :
J Bloomer Richard نويسنده Cardio respiratory/Metabolic Laboratory, The University of Memphis, Memphis, TN 38152, USA , Leelarungrayub Jirakrit نويسنده Department of Physical Therapy, Faculty of Associated
Medical Sciences, Chiang Mai University, Chiang Mai 50200,
Thailand , Pinkaew Decha نويسنده Department of Physical Therapy, Faculty of Associated
Medical Sciences, Chiang Mai University, Chiang Mai 50200,
Thailand , Klaphajone Jakkrit نويسنده Department of Rehabilitation Medicine, Faculty of
Medicine, Chiang Mai University, Chiang Mai 50200,
Thailand , Eungpinichpong Wichai نويسنده Research Center in Back, Neck, Other Joint Pain and Human
Performance, Khon Kaen University, Khon Kaen 40002,
Thailand
Abstract :
Background The effectiveness of L-carnitine supplementation has
been met with conflicting findings when used by sedentary and athletic
adults. Objectives This study aimed to investigate the acute effects of
L-carnitine supplementation on aerobic metabolic efficiency and lipid
profiles in sedentary and athletic men. Methods Fifteen sedentary (20.4
± 1.5 years) and 15 athletic (21.5 ± 2.4 years) men were studied in
durations of control, placebo intake and 2 g of L-carnitine
supplementation. Lipid profiles, including triglyceride, cholesterol,
high-density lipoprotein (HDL) and very-low density lipoprotein (VLDL),
were determined before and 40 min after either the placebo or
L-carnitine intake. Oxygen consumption (direct
VO2), ventilatory threshold (VT), and running
time (RT) were recorded after a submaximal treadmill exercise test.
Results Direct VO2 increased significantly at 80%
of maximal heart rate after L-carnitine supplementation in both athletic
and sedentary men, whereas, a statistical increase in VT and RT occurred
only after L-carnitine use in athletes, when compared to the control and
placebo subjects. The sedentary group showed no changes in lipid
parameters, but triglyceride levels reduced significantly in the
athletes after consuming L-carnitine. Conclusions Acute L-carnitine
supplementation possibly affects exercise performance and triglycerides
in athletes rather than sedentary men.
