|
Acetyl-L-Carnitine and Testosterone |
|
|
|
by Thomas Incledon, PhD(c), RD, LD/LN, RPT, NSCA-CPT, CSCS
Introduction
With all the hype and attention given to creatine monohydrate, HMB, and the prohormones other potentially useful supplements are being overlooked. One in particular is acetyl-l-carnitine or ALC for short. After reviewing tons of studies on this compound I thought it had lots of potential. I figured if given in the right amounts it would stimulate testosterone (T) production in weight-trained males with the hope that this would lead to greater gains in size and strength. One of my buddies tried it and guess what? His T levels increased about 13% after 30 days. I’ll give you all the details, but before that let’s review some basics and see how it can work.
ALC’s Effects on Testosterone Stimulating Hormones
To support my claims that ALC can raise T levels in resistance trained males I want to overview some of the studies done with this compound. First in 1991 some Italian researchers examined the use of ALC to treat women with hypothalamic amenorrhea (1). What the heck is that you ask and how does this relate to increasing T? Simply, these were women that were not menstruating regularly because they did not produce enough luteinizing hormone (LH). (This hormone stimulates T production by the same pathway in men). The researchers figured that ALC might stimulate gonadotropin releasing hormone (GnRH), which would then stimulate the production of LH. ALC administered at 2g per day did in fact increase LH levels in the women that started out with low LH levels. It also increased the LH levels in some women that started out with normal LH levels. A few years later a different group of Italian researchers studied the effects of ALC on GnRH and LH levels in female rats (2). Guess what? It increased levels of both hormones. Work with isolated cell cultures has also confirmed that ALC can stimulate GnRH release (3). I mention these studies so that you can see the effects of ALC on isolated cells, female rats and women were all similar—increases in hormones that can lead to greater increases in T production.
ALC’s Effects on Testosterone
So if ALC can increase GnRH and LH in women and female rats, the big question is can it increase T in men? Let’s find out. Yet another Italian research team studied the effects of ALC on reproductive function in male rats (these Italians sure love this ALC!) (4). They found that ALC increased the production of T. In 1993 another study on ALC and male rats was published (5). Here they swam the heck out of the poor animals. Now when you chronically overtrain, your T levels drop (This may be why your girlfriend doesn’t look so pretty any more!). These guys gave the rats some ALC (computed out to be about 50 mg/kg of bodyweight) to see if it could prevent the decrease in T that occurs with overtraining. They found out that it does (at least in male rats). After I had read all of this I though this stuff has to be able to increase T in men. One of my friends was curious to try it so we took some of his blood. Started him on ALC for 30 days at 1 g in the AM and 1 g in the PM. He weighed 90 kg so this works out to about 22.2 mg per kg of BW. This is much less then what the Italians were giving the rats. Now my buddy was a bodybuilder/powerlifter and had been training for several years. When his T levels were checked they had increased 13%. Now we only measured total T. Most of you will know that the free T and albumin bound T are really important in terms of muscle building and total T doesn’t tell us what happened to those fractions. My guess is that the free T would have increased by about the same amount.
Important Considerations and What To Expect
Bottom line here is that ALC should be able to increase T levels at the right dose. Will this lead to greater gains in size and strength? I believe it can—the question is how much do you need to take for it to work. Now don’t expect steroid-like results. It won’t happen because the increase in T is not big enough. It also won’t equal the increases in T that some of the prohormones are claimed to cause. It also won’t happen as fast as the results from a loading phase of creatine. So why take it? First off you don’t have to cycle its use like you would with other products. Secondly dozens of other studies have demonstrated many positive effects of ALC on the skeletal muscle and nerve cells. This has the potential to enable you to train harder and recover faster. A rationale way to begin is to start at the 2 g per day for 30 days. If you can, get your free T levels checked before starting the supplement. After 30 days get your free T levels checked again. Take 1 g in the morning and 1 g later in the day. It can also stimulate blood flow to the brain so my suggestion would be to take one of the doses about 30-60 minutes before going to the gym or before the part of the day comes when you start dragging (between 3-5 PM for most). Keep a diary about how you feel prior to going to the gym you should see an improvement in you mental focus. If not after 30 days increase the dosage. I know some guys that pushed the dosage too soon to 5 g twice per day. They had diarrhea which means they are leaving most of their ALC in the toilet. The rule of thumb for that is: Cut back on the dose until the diarrhea subsides, then gradually increase the dose to a level where you can feel a difference in your performance. The “gradual increase” and “feel a difference” are very individually determined measures. Feel free to email me with your questions, comments and concerns.
This email address is being protected from spam bots, you need Javascript enabled to view it
References
Genazzani, A. D., et al. Acetyl-l-carnitine as possible drug in the treatment of hypothalamic amenorrhea. Acta Obstetricia et Gynecologica Scandinavica. 1991; 70:487-492.
Krsmanovic, L.Z. et al. Actions of acetyl-l-carnitine on the hypothalamo-pituitary-gonadal system in female rats. Journal of Steroid Biochemistry and Molecular Biology. 1992; 43(4):351-358.
Krsmanovic, L.Z. et al. Stimulation of gonadotropin-releasing hormone secretion by acetyl-l-carnitine in hypothalamic neurons and GTI neuronal cells. Neuroscience Letters. 1994; 165:33-36.
Palmero, S. et al. The effects of L-acetylcarnitine on some reproductive function in the oligoasthenospermic rat. Hormones and Metabolism in Research. 1990; 22:622-626.
Bidzinska, B. et al. Effect of different chronic intermittent stressors and acetyl-l-carnitine on hypothalamic B-endorphin and GnRH and on plasma testosterone levels in male rats. Neuroendocrinology. 1993; 57:985-990.
|
Resource Library HTML