Nutrex T-UP Black is One Amazing Testosterone Booster!
What is a testosterone booster supplement? And what's in a testosterone booster? The typical run-of-the-mill test booster you'll find on the market helps to increase one's natural testosterone production, and this is often achieved through the inclusion of various common ingredients such as tribulus, tongkat-ali, avena sativa, fenugreek, horny goat weed, and stinging nettle extract. Most of these may be familiar to you if you've looked at the ingredient label of any test booster supplement. You'll often find some, or all of these ingredients in various testosterone boosting supplements.
These ingredients all work in different ways to help increase testosterone levels. Some do so through stimulating lutenizing hormone (LH), some help increase libido and sexual desire, others bind to SHBG (sex hormone binding globulin) to increase free testosterone levels, while others help minimize estrogen. With so many different test enhancers on the market, it can be a tough choice to pick and choose the right one. One top rated testosterone booster is the T-UP Black by Nutrex. Nutrex also makes another top rated testosterone booster called Nutrex Vitrix, which we also have a review for.
Here, we'll be doing the review on Nutrex TUp Black.
Nutrex TUp Black Ingredients
The reason we brought up the issue of the common testosterone booster ingredients above is because T-UP Black is a very different test booster compared to what you'll find on the market. In fact, it's so different that it doesn't contain any of the above mentioned ingredients, and that its formula is so simple that it contains just a handful of ingredients! So let's take a quick look at what these are below:
Sodium D-Aspartic Acid
What? That's it? Yep... It's a little strange to see a testosterone booster with so few ingredients. The two key ingredients in TUp Black are sodium d-aspartic acid and massularia acuminata. Let's see how these ingredients function.
Sodium D-Aspartic Acid is an amino acid found in neuroendocrine tissues, and it has been found in studies to increase the release of LH and testosterone in rats and humans. In vivo (within living organism) experiments have found it to significantly increase lutenizing hormone and testosteron, while in vitro (test tube) experiments found it to induce the synthesis of testosterone.  Sodium D-Aspartic Acid is involved in the regulation of hormone synthesis and release. It also stimulates the secretion of lutenizing hormone and growth hormone (GH) in the testes, and it is also involved with testosterone and progesterone release. 
Studies of Sodium D-Aspartic Acid have also been performed on human subjects. In one study, 23 male subjects were given D-Aspartate for 12 days, and another 20 men were given a placebo. The results found that Sodium D-Aspartic Acid induced an enhanced release of LH and testosterone. This same study using rats as test subjects found similar increases in LH and testosterone. 
The other interesting ingredient in Nutrex TUp Black is Massularia Acuminata (MA). Various studies have found it to have testosterone boosting and libido enhancing effects. Its stem has been used as an aphrodisiac, and new studies have confirmed its libido boosting effects. 60 male rats were given 250, 500, 1000mg/kg body weight of the Acuminata extract, or a placebo. The treatment groups were found to have significantly increased sexual behavior, and at the same time, the study also found that the extract also increased the serum testosterone levels of the animals. 
Other similar studies with lower doses of the extract had similar findings. One study used doses of 50, 100, and 200mg/kg of body weight, and it found MA to have strong prosexual effects. This study also found that concentration of serum testosterone levels also increased.  There are many such studies with similar finding. One study stated: "The available evidence in this study suggests that aqueous extract of Massularia acuminata stem has androgenic potential which may stimulate male sexual maturation and enhance normal testicular function." 
While there are numerous studies done on Massularia Acuminata, I could only find ones done on rats, and not on human subjects. However, so far, the results look very promising.
Nutrex T-Up Side Effects
The combination of Massularia Acuminata and Sodium D-Aspartic Acid sounds promising as an effective testosteron booster from what we've seen so far. Both work to help increase testosterone levels and increase libido. So how well does Nutrex T-Up work? First of all, I didn't experience any side effects from using TUp, and I'm not aware of many T-Up side effects either - with the exception of perhaps some increase in acne breakouts and aggression, along with other effects associated with an increase in testosterone levels.
For me, while using Nutrex TUp Black, there was noticeable increase in strength and some minor increase in aggression, particularly noticeable during my workouts. The effects were exceptional. I was lifting quite a bit heavier in all my lifts, and put on a little extra size and lean weight. The aggression wasn't bad, and it was mainly there during my workouts which was great for blasting through the grinding workouts. I looked and felt denser, and the libido boost was very, very noticeable! I would have to say that Nutrex T-UP Black is close to being one of the best testosterone booster on the market.
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