Do They Increase Libido? What About Muscle?
by TC Luoma T-Nation
A couple of weeks ago, I read a Facebook post from a fairly well known nutrition writer. It said something along the lines of how testosterone boosters don’t work. No explanation, just a one-sentence statement tossed out into the electronic wind.
Ordinarily I might have ignored such a post, but the guy had pulled out the periwinkle background and the big font, so I knew he was serious.
Man, you don’t pull out the periwinkle background and big font on Facebook for just any reason; you save it for super important stuff, like how maybe you’re a genius or something because you answered 8 out of 10 questions correctly in that quiz written for morons, or how you like dumplings.
Anyhow, when this guy with the color and the big font disparaged testosterone boosters, I took notice, as did a lot of his followers who seemed to agree with him by liking his post.
Mind you that these are largely the same people who think you can use supplements to lower cortisol levels, improve insulin sensitivity, block estrogen, or affect any number of biochemical reactions or processes, but using them to raise testosterone?Volume 90% X
That’s voodoo stuff. You take your black magic and go straight back to whatever devil’s VRBO you and your coven of sorcerers are staying in, mister!
But I guess I can see why these testosterone-booster disparagers think the way they do. They’re no doubt comparing these supplements to actual testosterone replacement with the ampoules and needles and syringes.
I’ll readily admit that no testosterone booster on the market will work as well as injecting 100 mg. or more of testosterone cypionate into your left glute or, for that matter, your right glute.
Many of these supplements DO increase testosterone levels, though. Products like forskolin carbonate and Eurycoma longifolia (aka Tongkat ali and Malaysian ginseng) are extremely effective in providing a modest boost in testosterone – maybe not enough to jack you up, but enough to either bring you back up to where you’re supposed to be or just give you a little boost so that making muscle, losing fat, or making love is just a little easier.
One of the earliest of these testosterone boosters was the herb, Tribulus terrestris, which Biotest markets as Tribex®. It’s lately been the subject of new research and it deserves a second look.
Why Haven’t You Heard Much About Tribulus?
Tribulus terrestris (TT) comes from a small, leafy plant and it’s commonly known as puncture vine, caltrop, or goat’s head and it grows in Asia, Africa, and the Middle East, but the best stuff, the Tribulus-equivalent of Ethiopian or Columbian coffee, is Bulgarian-grown Tribulus.
The herb has long been used in traditional Chinese medicine and India Ayurveda medicine to enhance libido, establish hormonal balance, and keep the urinary tract healthy.
The thing is, I’ve never really promoted it much. I wasn’t perfectly comfortable doing so. Oh, Biotest’s internal, non-peer reviewed research showed that this herbal aphrodisiac worked well in raising testosterone levels and increasing sports performance, but the formal, published-in-journals research was all over the place – some studies showed that it worked, and others showed that it didn’t.
Regardless, we’ve always assumed that the results from clinical studies were sometimes lackluster because researchers were probably using TT that wasn’t potent; stuff that might have been grown in poor soil or picked at the wrong time and wasn’t at all standardized to contain the highest percentage of the active ingredients.
Some Japanese researchers recently backed us up on that theory. Writing in a study on the positive effects of TT on intensely trained male boxers, they guessed that the content of the biologically active compounds 25(R)-Spirostan-3,6,12-trione/25(R)-Spirostan-4-ene-3,12-dione and saponin A vary “depending on geographical region, climate, and parts of the herb, which may partly explain the divergent results of TT extracts from different studies.” (Ma, 2015)
I’ll get to these climate-affected divergent results later, but let’s first examine exactly what happened in that study of boxers, along with another study that tested the effects of the herb on middle-aged men when standardized samples were used.
The Boxers vs. Middle-Aged Men
The study involving boxers was designed to see how TT affected muscle mass, muscle damage, and anaerobic performance and whether any of that might have been influenced by changes in IGF-1, GH, or testosterone.
The researchers split 15 boxers into two groups:
“All athletes received similar 3-week high intensity training and 3-week high volume training separated by a 4-week rest. Besides special technical training, the main part of the high intensity training was strength training including maximum strength training (twice a week) and speed training (twice a week, on different days than the strength training).”
The exercise plus TT group received 1250 mg. a day of a standardized Tribulus extract. After concluding the training program, the boxers in the TT group showed increased muscle power, less muscle damage, and increased levels of IGF binding protein (IGFBP-3).
In a second study, Polish scientists tested 14 men between the ages of 45 and 60 (which is a population that’s more likely to be experiencing a decline in testosterone production) for 12 weeks. For the first 6 weeks, the guys in the experimental group were given 900 mg. of TT in split doses. From weeks 6 to 12, the men received 1,800 mg. in divided doses.
All men, including the controls, performed a generally well thought-out resistance-training program. At the end of 12 weeks, the men in the TT group showed the following:
- 12% increase in testosterone
- 11% increase in GH
- 20% increase in IGF-1
- 7% loss of body fat
- 4% decrease in LDL
- 7% increase in HDL
What to Make of this Data
Historically, we’ve thought that TT works because it contains high levels (at least in standardized extracts) of protodioscin, a steroidal saponin. In turn, this steroidal saponin may act as a luteinizing-hormone secretagogue, which just means that it prompts the pituitary to kick out more luteinizing hormone (LH). This surge of LH then prompts the testes to produce more testosterone.
That may or may not be true. No one knows for sure. TT certainly increases levels of testosterone, but it’s possible it has more to do with inhibition of key enzymes responsible for the unwanted conversion of testosterone to estrogen and DHT. After all, if you inhibit conversion, you automatically ensure higher levels of testosterone.
Others think that TT may enhance androgen receptor density in the brain (and possibly muscle tissue, too). That means that testosterone has a lot more places to park and do its stuff.
I feel compelled to point out, though, that this increase in testosterone might only occur in people who are testosterone deficient, as was the case in the study involving middle-aged men.
Conversely, the young boxers in the first study didn’t exhibit much of a change in testosterone levels after being supplemented with TT, maybe because their initial testosterone levels were presumably up to snuff; i.e., they weren’t deficient. Regardless, they did exhibit increased power and less muscle damage than controls.
This led to speculation by the scientists that TT may, by decreasing levels of the IGF binding protein IGFBP-3, lead to increased activity of IGF-1. For those of you who don’t know much about IGF-1, it’s GH’s errand boy. Once the pituitary cranks out some GH, it tells the liver to make IGF-1, which then proceeds to stimulate every type of cell in the body, including, of course, muscle cells.
So here’s what it looks like: If you’re deficient in testosterone because of age, genetic factors, nutritional factors, environmental factors, or psychological factors, standardized TT can help bring testosterone levels into healthy ranges.
But, regardless of whether your testosterone levels are low, it appears TT can also increase sports performance and prevent training-induced muscle damage by increasing activity of IGF-1, which can, over time, lead to increased muscle mass.
What About Sex and Stuff?
As I mentioned earlier, TT has long been used as an aphrodisiac and a number of studies have confirmed its pro-sexual use. One in particular found that consuming 750-1,500 mg. of TT daily for two months led to a 79% increase in male sex drive. Similarly, 67% of women who consumed 500 to 1,500 mg. a day for 90 days experienced increased sexual desire. (Neychev 2016)
While the credit for these pro-sexual effects has long been given to TT’s androgen-increasing properties, there’s “emerging compelling evidence” from animal studies to suggest that there are some endothelium and nitric oxide-dependent mechanisms underlying TT’s effectiveness in this regard.
Erections are all about hydraulics, and if you relax the endothelium of blood vessels and increase the production of nitric oxide, you get a more functional erection. Females respond in much the same way to an increase in nitric oxide, too. The blood flow to the clitoris increases, causing clitoral engorgement, extrusion of the glans clitoris, and thus enhanced sensitivity.
Don’t Buy Grass Clippings
So it appears TT’s effectiveness comes down mostly to strength and purity. As described earlier, the best Tribulus terrestris comes from Bulgaria, and it’s the only type Biotest uses in its Tribex® formulation.
The Bulgarians know exactly when to harvest their Tribulus plants and, more importantly, they know which parts of the plant to use. For instance, they’ve discovered that levels of saponins and other powerful compounds increase before and during the flowering stage, while decreasing during the stage when fruit is produced.
Likewise, they know that the leaves and roots have the highest concentration of saponins, followed by the fruits and stems.
Don’t assume, though, that Biotest is simply jamming those Bulgarian leaves and roots into a capsule the same way your grandma jams loose tea leaves into her Martha Stewart-collection tea infuser. No, they use a highly purified extract.
While each 2-capsule serving of Tribex® contains 500 mg. of Tribulus terrestris, it’s formulated at a 50:1 extraction ratio. That means that it has 50 times the full-spectrum of active ingredients (but predominantly protodioscin) as the original herb in dried form.
But if you don’t do all of the preceding, if you don’t take all these factors into consideration, you can easily arrive at a product that’s essentially worthless; little more than grass clippings.
This attention to detail allows Biotest to produce the most potent, full-spectrum extraction of Bulgarian Tribulus in the world.
All of this brings us back to the question posed by the title of this article: Do Testosterone Boosters Work? Well, there shouldn’t be much argument in accepting that forskolin carbonate and Eurycoma longifolia, at least, are effective in raising testosterone levels, but given the recent research, we can now comfortably add Tribulus terrestris to their ranks.
- Yiming Ma, et al. “Tribulus terrestris extracts alleviate muscle damage and promote anaerobic performance of trained male boxers and its mechanisms: Roles of androgen, IGF-1, and IGF binding protein-3,” Journal of Sport and Health Science, Volume 6, Issue 4, December 2017.
- Ricardo Munarriz, et al. “Biology of Female Sexual Function,” Boston University School of Medicine, Sexual Medicine.
- Vladimir Neychev, Vanyo Mitev, “Pro-sexual and Androgen Enhancing Effects of Tribulus Terrestris L.: Fact or Fiction,” J Ethnopharmacol. 2016 Feb 17;179:345-55.
- Ivanka Semerdjieva, Valtcho Zheljazkov, “Chemical Constituents, Biological Properties, and Uses of Tribulus terrestris: A Review,” Natural Product Communications, August, 2019: 1-26.
- Michal WIlk, et al. “Endocrine Responses to Physical Training and Tribulus Terrestris Supplementation in Middle-Age Men,” Central European Journal of Sports Sciences and Medicine, Vol. 13, No. 1/2016: 65-71.