Carnipure™ has long been discussed in the world of athletics, sports and recovery, and numerous studies have been published regarding its effects on exercise performance and recovery. In this version of the Carnipure™ focus we will summarize a new and exciting line of research which represents a new paradigm for Carnipure™ and its ability to aid in the recovery process. This new paradigm shows a novel role for Carnipure™ and its ability to optimize recovery by reducing the hypoxic effects created during exercise. The studies discussed will show how Carnipure™ aids in the recovery process through increasing blood flow, reducing markers of metabolic stress, decreasing muscle soreness, and improving recovery time. In addition, the second part of this brochure will focus on new research to support the old paradigm: that supplementation with Carnipure™ can increase muscle carnitine content.
What is Carnipure™?
Carnipure™ is high quality L-carnitine manufactured by the Swiss lifescience company Lonza. Products displaying the Carnipure™ quality seal on the packaging show the consumer that they contain pure L-carnitine from Lonza which is backed by sound scientific research.
Carnipure™ and recovery after exercise
Proving this new paradigm for Carnipure™ has been a focus of development for the past decade. The main reason for starting such research was to help support the recovery efforts of individuals trying to stay fit and healthy. The first complaint usually noted by individuals who start to exercise or get back into a gym routine is muscle soreness. Typically, after 48 hours muscle aches begin to develop which usually causes the individual to stop working out. Therefore, it was the main focus of researchers at the University of Connecticut to try to provide a technology that would aid in reducing muscle soreness and improve the recovery from these activities. This section will detail the different studies in which Carnipure™ has been researched with regards to decreasing muscle soreness and pain and explain the effect of Carnipure™ at the metabolic level. This new paradigm was built on the potential of enhancing the storage of L-carnitine in the endothelium of the smooth muscle within the capillary sphincter beds. Research has shown that a high concentration of L-carnitine in these sphincters leads to a dilation effect. Dilation allows for increased blood flow and subsequently greater oxygenation of muscle tissues. In addition, this section will also discuss the effectiveness of supplementation at different levels as well as the impact of Carnipure™ across the age spectrum.
Carnipure™ and blood flow
In times of training and exercise, lack of oxygen to the appropriate cells may lead to hypoxia. Exercise stress is known to cause hypoxia in capillary endothelial cells. This lack of oxygen can lead to markers of metabolic stress, such as purine catabolism and free radical generation. Free radicals can cause damage to the capillary membranes, thereby decreasing capillary integrity. This in turn can decrease blood flow to muscles. To counteract this phenomenon after exercise, research has looked into the role of Carnipure™ in capillary dilation. It has been found that endothelial cells which depend upon fatty acid metabolism for energy and L-carnitine may be depleted during stress, thereby compromising blood flow. Carnipure™ supplementation may restore levels of L-carnitine in endothelial cells during times of metabolic stress or exercise. Such restoration would increases endothelial cell integrity and promotes dilation and blood flow to appropriate tissues. To illustrate this concept, Volek et al. showed that supplemental Carnipure™ improved blood vessel dilation after a high fat meal, which is a known stressor to vascular endothelial cells. Reduced levels of hypoxia from Carnipure™ supplementation can reduce negative effects of purine catabolism which leads to improved recovery after exercise. Purine catabolism encompasses a cascade of effects within a cell which can lead to production of free radicals and cell membrane disruption. Such membrane disruption necessitates tissue repair, which increases the time needed for exercise recovery. In a crossover, placebo controlled study, it was shown that Carnipure™ supplementation decreased markers of purine catabolism. Participants of the study took either Carnipure™ tartrate (equivalent to two grams L-carnitine per day) or a placebo for three weeks prior to the performance of a controlled exercise session. The study results indicated that supplementing with Carnipure™ tartrate prior to high intensity exercise can decrease the biochemical and structural stress responses and therefore be effective in assisting recovery.In another study published in 2008, researchers showed that Carnipure™ supplementation decreased levels of malondealdehyde, a marker of membrane disruption. This decrease indicates that Carnipure™ is able to contribute to the integrity of cell membranes of muscle tissue and to the capillary endothelial cells which supply nutrients and oxygen to muscles. To test the effect of Carnipure™ on exercise recovery, Volek et al. also measured direct and indirect markers of stress. Results demonstrated that indirect markers of muscle damage (creatine kinase, fatty acid binding proteins, and myoglobin) were positively influenced by supplementation of Carnipure™. To further support these indirect markers (magnetic resonance imaging) scans were taken prior to and after exercise to show a direct effect on the muscle tissue. Results from the (MRI) scans further support the muscle recovery ability of Carnipure™ as individuals receiving Carnipure™ showed close to a 40% reduction in overall muscle damage. In addition to these markers, researchers also measured the effects of Carnipure™ supplementation on perceived muscle soreness using subjective quality scores. Participants in this study consistently rated muscle soreness at a lower level when taking Carnipure™ as opposed to the placebo. This clearly shows the positive effect of Carnipure™ on muscle recovery not only immediately after exercise but also up to three days following exercise.
Carnipure™ and protein synthesis
Another way in which Carnipure™ has been shown to improve recovery after exercise is mediated through hormonal contributions. It has been postulated that L-carnitine upregulates androgen receptors, thereby leading to increased protein synthesis. A study published in 2006 investigated the effects of Carnipure™ supplementation and androgenic response after resistance exercise. It was found that Carnipure™ supplementation upregulated androgen receptors and in conjunction with decreased muscle damage led to an increased cellular uptake of testosterone. Another study found Carnipure™ supplementation decreased exercised induced muscle tissue damage by as much as ten percent as compared with placebo. This allows for an increase in intact hormone receptors for enhanced binding interaction. This in turn can increase protein synthesis and muscle repair thereby improving recovery after exercise. This could be an additional mechanism by which Carnipure™ influences recovery.
Carnipure™ across the age spectrum
The effects of Carnipure™ as they relate to exercise and recovery have traditionally been studied in young, exercise trained participants. However, as the global population continues to age, it is also important to examine the effects of Carnipure™ in the so-called baby boomer generation. This group, born after the Second World War and now in the range of 50 to 65 years of age, represents a generation who is still active and would benefit from a supplement which can improve recovery after exercise. In a study by the Human Performance Laboratory of the University of Connecticut, researchers aimed to explore the impact of Carnipure™ supplementation in an untrained, middle aged population. In this double blinded crossover design trial, which included men and women, analysis of the results found that Carnipure™ supplementation decreased markers of purine catabolism and reduced muscle soreness. As a result of this study Carnipure™ supplementation has been shown to have beneficial effects regarding recovery in a broad spectrum of ages as well as level of training.
Daily effectiveness of Carnipure™
It has also been noted that Carnipure™ is an effective supplement even at doses lower than those used in the studies mentioned above. While two grams of elemental L-carnitine being supplied by Carnipure™ tartrate has been used in numerous studies, it is also beneficial to study the impact of supplements at lower doses in order to ascertain the full range of benefits. In a dose response analysis, researchers used a randomized, crossover design study to look at the effects of Carnipure™ on metabolic markers of stress. After evaluating the results, it was found that one gram elemental L-carnitine being supplied by Carnipure™ tartrate per day decreases markers of metabolic stress due to exercise as compared with the placebo. Furthermore, there was no significant difference between one gram and two grams for Carnipure™ in the reduction effect for certain metabolic markers, such as hypoxanthine. This study shows that even at low levels, Carnipure™ tartrate supplementation can be effective in reducing the damaging effects of post exercise metabolism.
New research for the old paradigm
As research in Carnipure™ has focused on improving recovery after exercise by mediating hypoxia, it is still important to consider the notion that supplementation can increase intracellular levels of L-carnitine in the muscle. This may be especially important for athletes as research has shown that athletes may have a decreased level of L-carnitine in the body and may benefit from supplementation. This section provides a summary of the research in this area and also discusses a new research study
published in 2011 regarding the impact of Carnipure™ supplementation on muscle L-carnitine levels and fuel utilization during exercise.
Athletes have low L-carnitine levels For the general population, although an endogenous biosynthesis pathway exists, L-carnitine largely comes from dietary intake, namely meat. Foods of plant origin contain very little, if any, L-carnitine. As public health experts have recommended decreasing intake of red meat and athletes often wish to consume a carbohydrate rich diet and omit meat, L-carnitine from dietary intake may be insufficient. Researchers have observed that high performance athletes, such as triathletes, who follow an omnivorous diet, may still have lower than normal plasma levels. In athletes, this has been attributed to higher excretion of L-carnitine via the kidneys14 and via perspiration. This loss may be followed by a decrease of L-carnitine in the active muscles which may not always be rapidly replenished.17 Moreover, studies show that as exercise intensifies, the concentration of acyl-Lcarnitine within the muscle increases and the availability of free L-carnitine decreases. Decreased availability of free L-carnitine in the mitochondria may lead to a decreased capacity of all energy generating pathways.
What is L-carnitine?
L-carnitine, the biologically active isomer of carnitine, is a natural substance that can be found ubiquitously in mammalian tissues and plays a key role within several cellular energy producing pathways.
Its main metabolic function is to transport long-chain fatty acids into the mitochondrial matrix for beta oxidation and energy generation. Therefore, L-carnitine is necessary for the utilization of fatty acids for energy and is important in exercise and sports as fatty acids are the main source of fuel for endurance athletes.
New research on Carnipure™ supplementation
Prior research has found conflicting results with respect to increasing intracellular levels with supplementation, however a study published in 2011 has found that L-carnitine content can be increased when taken in conjunction with an insulin stimulating substance, such as carbohydrate. Researchers not only found that muscle L-carnitine increased after Carnipure™ supplementation but such supplementation also positively impacted substrate utilization in low intensity exercise and lactate accumulation in high intensity exercise. Specifically, research showed that an increase in muscle L-carnitine content decreased the use of glycogen during low intensity exercise. This is a significant finding to support the notion that Carnipure™ can increase lipid oxidation and decrease glucose utilization. Practically speaking, such glucose sparing during low intensity exercises could potentially improve performance by prolonging the use of glycogen as fuel. During high intensity exercise, decreased lactate accumulation was attributed to an increase in pyruvate dehydrogenase complex, which increases availability of acetyl-CoA for aerobic energy generation. Overall work output was also improved in the Carnipure™ group, likely due to the observed changes in muscle metabolism. The study discussed here represents an emerging area of research to help validate existing theories on the impact of Carnipure™ supplementation during exercise and recovery.
Data discussed in this brochure clearly establishes that a new paradigm exists of Carnipure™. This novel paradigm places Carnipure™ in the important role of facilitating the recovery process in response to physical activity. In this role, Carnipure™ helps to protect the endothelial cells from an L-carnitine deficiency (thereby positively influencing the markers of purine catabolism), reduce tissue damage and muscle soreness and facilitate the overall process of recovery. Therefore, Carnipure™ is emerging as a key ingredient in exercise and recovery type formulations across the globe.
1. Hülsmann WC & Dubelaar ML (1992). Mol Cell Biochem 116:125–129
2. Kraemer WJ et al. (2005). Chemical Monthly 136:1383–1390
3. Volek JS et al. (2008). Am J Cardiol 102:1413–1417
4. Volek JS et al. (2002). Am J Physiol Endocrinol Metab 282:E474
5. Spiering BA et al. (2008). J. Strength Cond Res 22(4):1130–1135
6. Kraemer WJ et al. (2006). Med Sci Sports Exerc 38(7):1288-1296
7. Kraemer WJ et al. (2003). J Strength Cond Res 17(3):455–462
8. World Health Organization (2007). www.who.int/features/factfiles/ageing/en/index.html
9. Ho JY et al. (2010). Metab 59:1190–1199
10. Spiering BA et al. (2007). J Strength Cond Res 21(1):259–264
11. Bremer J (1983). Physiol Rev 63:1420-1480
12. Bremer J (1990). J Clin Chem Clin Biochem 28(5):297–301
13. Steiber A et al. (2004). Mol Aspects Med 2 (5-6):455–473
14. Luppa D et al (1996). In: Seim H & Loster H (eds): Carnitine – Pathobiochemical Basics and Clinical Applications. Ponte Press, Germany
15. Suzuki M et al. (1976). J Nutr Sci Vitaminol 22:169–174
16. Arenas J et al. (1991). Muscle and Nerve 14:598–604
17. Cerretelli P et al. (1990). Int J Sports Med 11:1–14
18. Van Loon et al. (2001). J Physiol 536(1):295–304
19. LeBlanc PJ et al. (2004). J Appl Physiol 97:2148–2153
20. Nüesch R et al. (1999). Drugs Exptl Clin Res 25(4):167–171
21. Wall BT et al. (2011). J Physiol 589(4):963–973
Foto: © Adriana Williams