Acute Effect of L-Carnitine Supplements on Lactate, Glucose, Saturated Oxygen and VO2max Variations in Young Males

Abstract

Introduction: L-carnitine may improve athlete's performance by increasing lipids oxidation. The goal of the present study was to assess the acute impact of L-carnitine supplements on lactate, glucose, saturated oxygen and VO 2 max levels in young men. Methods: Ten young males completed 2 sessions of exhausting exercise (Bruce test). In the first session, the participants consumed placebo and in the second session, they consumed 3 g of L-carnitine 90 minutes before the test. The 2 sessions were 1-week apart. Then dependent parameters were measured. Results: A significant difference was detected in VO 2 max and lactate between the placebo and supplement groups (P < 0.05) but the difference between glucose, saturated oxygen and heart rate was not statistically significant (P > 0.05) between the 2 groups. Conclusion: The present study showed that L-carnitine supplementation before exercise decreases lactate and increases VO 2 max in young men.

Effect of Oral Supplementation with L-Carnitine on Performance Time in a 5000 m Race and Responses of Free Fatty Acid and Carnitine Concentrations in Trained-Endurance Athletes

“…Smith et al (2008) showed no differences between or within groups in muscle (Vastus lateralis) carnitine content, time to fatigue, and anaerobic power in untrained men and women after eight weeks of L -carnitine supplementation (1 g/day, 3 g/day, or placebo). Kashef & Saei (2017) observed an increased VO 2max during testing to exhaustion (Bruce incremental exercise) following acute ingestion of 3 g of L -carnitine 90 min prior to testing compared to the placebo group in students. Vecchiet et al (1990) demonstrated enhanced incremental cycle ergometer performance following a single dose of L -carnitine (2 g) 1 h prior to exercise compared to placebo in collegiate students.…”

“…Although the plasma FFA value measured for all athletes in both groups did not exceed reference range values by means, data analysis revealed a significant decrease in its value three weeks after L -carnitine supplementation compared to the Placebo group. This might indicate an increased cellular uptake of fatty acids from blood and subsequent enhanced transportation of fatty acids into mitochondria for β-oxidation (Kashef & Saei, 2017). Delaš et al (2008) demonstrated that L -carnitine supplementation (2 g/day for 2 weeks) only in sedentary healthy subjects did not induce changes in blood glucose, triacylglycerols, total cholesterol, high-density lipoprotein (HDL), creatine kinase; however, the FFA level was decreased from 0.439 mmol/dry muscle to 0.279 mmol/dry muscle.…”

“…It has been reported that elevation in plasma fatty acid availability prior to exercise could reduce utilization of muscle glycogen (Brass & Hiatt, 1998;Smith et al, 2008), which promotes an important pathway to spare glycogen stores (Wall et al, 2013;Brass & Hiatt, 1998;Kashef & Saei, 2017) and subsequent improvement in endurance capacity. However, the fatty acid oxidation ratio is decreased when an exercise intensity exceeds 70% VO 2max (Wall et al, 2013), and glycolysis is increased (Peters et al, 2015;Wall al., 2013).…”

“…To the best knowledge of the author of the present paper, several studies have studied the effect of L -carnitine with acute ingestion (Eizadi, Pourvaghar, Nazem, Eghdami, & Khorshidi, 2009;Kashef & Saei, 2017;Mojtaba et al, 2011;Vecchiet et al, 1990) and different supplementation periods (Greig et al, 1987;Smith et al, 2008;Wächter, Vogt, & Kreis, 2002); most of those studies focused on maximal oxygen consumption (VO 2max ) measurements on a cycle ergometer and conducted on healthy untrained subjects. However, no study has investigated the concentration of carnitine following a middle-distance race, such as 5000 m in endurance athletes.…”

The Effects of L-Carnitine Supplementation During Concurrent Training on the Functional Capacities and Body Composition in Obese Men

“…This issue was probably due to the low tolerance of lactate in the blood and some changes to intracellular biochemicals in the participants. 24 Kashef and Shabani observed that L-carnitine had a positive relationship with oxygen saturation, because the participants were active men and athletes, 24 and other studies reported high level of physical fitness of the participants. 25 26…”