Review: USP Labs Anabolic Pump/P-Slin

Review: USP Labs Anabolic Pump/P-Slin

Note: P-Slin is discontinued.

USP Labs’ Anabolic Pump is advertised as a “Selective Insulin Muscle Sensitizer,” that “…forces your body to naturally become super efficient in utilizing insulin only in muscle cells.P-Slin is billed as a “super-extracted version” of Anabolic Pump, so it seems appropriate to review both supplements together.

So what are these supplements supposed to do?

Anabolic-Pump™ creates a phenomenon called “Super Nutrient Partitioning.” Super Nutrient Partitioning involves the creation of a metabolic environment in which nutrient energy is selectively retained in muscle tissue rather than fat…Anabolic-Pump™ forces your body to naturally become super efficient in utilizing insulin only in muscle cells. The miraculous nature is that it completely shuts down the fat cell’s affinity to store glucose and triglycerides while causing lipolysis!

“P-Slin is specially designed to be used pre-workout when “nutrient-flooding” is most useful to the body to promote strength, size, definition, pumps, endurance and vascularity.”

In essence, USP Labs claims that Anabolic Pump and P-Slin will allow users to consume large amounts of carbohydrates, and ensure that they’re used for lean muscle growth, rather than fat gains. In fact, they state that users can actually lose body fat, while adding muscle.

Does this sound like a dream come true, or what?

But wait! Don’t reach for your wallet just yet. Let’s take a look at the ingredients and see how well they match up with the claims.

Anabolic Pump
Serving Size 1 Capsule
Servings Per Container90+

Amount Per Serving

AnabolicPump™ 750mg
P-Insulin™ (Extract Engineered From Phellodendron HCL)

Tannins Complex™ (Extract Engineered From Lagerstroemia Speciosa)

Symmetry™ (Herbal Engineered Ketones From Cissus Quadrangularis)

Serving Size 1 Capsule
Servings Per Container30

Amount Per Serving

Pure Blend 500mg
Tannins Complex™(Extract Engineered From Lagerstroemia Speciosa)

Gymnemic Complex(Herbal Engineered From Gymnema Sylvestre)

Anabolic Pump contains only 3 ingredients: Phellodendron HCl extract, Lagerstroemia speciosa extract, and “herbal engineered ketones” from Cissus quadrangularis. P-Slin has 2 ingredients: Lagerstroemia speciosa extract (same as Anabolic Pump), and Gymnema sylvestre extract. It’s not a long list, so let’s see what each one has to offer.

Phellodendron amurense is otherwise known as “Amur Cork Tree.” A native of Asia, the bark has been used in Chinese traditional medicine to treat gastrointestinal problems, ulcers, diabetes and infections.

Berberine is the best characterized of the compounds that have been identified. Berberine has antibacterial, anti-tumor and antioxidant activities. It may also have anti-diabetic activity: in one study, it decreased body fat and fasting glucose levels in rats. This work is not conclusive, however, as the berberine was administered by injection, not consumed orally. Unfortunately, we don’t have many other in-vivo studies on berberine or Phellodendron.

The only study on humans I could find in Western, peer-reviewed literature is on Phelldendron extract combined with Magnolia officinalis. This combination, currently sold as Relora, reduced weight gain in obese subjects by decreasing cortisol and stress-related eating. Thus, Phellodendron is promising, but much more research remains to be done.

Lagerstroemia speciosa is Banaba—a tree native to Southeast Asia. The leaves have been used in traditional medicine in the Phillipines as a treatment for diabetes. As it turns out, the leaves are high in corosolic acid, which has been shown to improve glucose control in human and animal studies. It appears to do this by stimulating glucose uptake in muscle cells. Glucose transport is mediated by specific transporter proteins. Corosolic acid acts by increasing the amount of a particular transporter (GLUT-4) on the cell membrane surface. Although more work remains to be done, banaba looks like a useful ingredient for treating hyperglycemia and diabetes.

Cissus quadrangularis is also known as “Veld Grape.” It’s another medicinal plant native to Africa, India, and other parts of Asia. Cissus has traditionally been used to treat a variety of ailments such as bone fractures, ulcers, wounds, indigestion and asthma. Animal studies have shown Cissus extracts may have gastroprotective effects, contribute to bone health, and have antioxidant/antimicrobial activities. A number of people swear by Cissus as an analgesic and use it to treat weight lifting injuries.

Lately, Cissus has also been touted as a fat loss agent, thanks to two studies.

The first was discussed by Paul in his review of Cylaris. Of course, this study actually tested the entire Cylaris formula—which makes it difficult to draw conclusions about Cissus itself.

A second study, however, did test a proprietary Cissus extract (CQR-300) and concluded it “…brought about significant reductions in weight and blood glucose levels, while decreasing serum lipids thus improving cardiovascular risk factors.

So is Cissus effective for reducing blood glucose and enhancing fat loss? Personally, I’m somewhat skeptical.

I’ve seen plenty of user reviews of bulk Cissus extracts for pain/injury relief, yet have never seen any that mentioned fat loss as an effect. I’ve used it myself as well, and noticed no changes in body composition. My doubts have not been assuaged by these studies, either.

Although they concern two different commercial formulations, both were performed by the same lead researcher: Julius Oben. And as it just so happens, Dr. Oben has a patent on the use of Cissus quadrangularis as a fat loss agent. This is an apparent conflict of interest, and I would prefer to see some confirmation from an independent laboratory before recommending Cissus for fat loss or glycemic control.

Gymnema sylvestre is native to India, and its leaves are a traditional folk medicine for diabetes. Several studies in humans and animals have confirmed it can improve glucose control, possibly by inhibiting glucose uptake in the small intestine and enhancing insulin release. It may even have positive effects on lipid metabolism and has potential for use in treating diabetes and obesity.

Of the three ingredients in Anabolic Pump, the evidence is strongest for banaba. This ingredient is also included in P-Slin, along with Gymnema—another promising extract. Thus, there is some decent evidence that these two supplements can, in fact, assist with glycemic control, although the extent is not known. USP Labs claims that “clinical studies” have been done, and provides several graphs on their web site. From the descriptions, however, these appear to be from cell culture (in-vitro) studies, so they don’t tell us much about how Anabolic Pump or P-Slin work in humans when taken as directed.

I gave these two supplements a try myself. After checking out the diet directions on the USP Labs forum, I stocked up on brown rice, sweet potatoes, oatmeal, and a few other complex carb sources, along with waxy maize starch for pre- and post-workout. I made sure to get a minimum of 50 g complex carbs in the three meals I took Anabolic Pump with, and consumed a solid 75 g of carbs pre-workout, as recommended for P-Slin. This is fairly carb-intense for me, as I prefer to get most of my carbs from veggies, fruits and some dairy products, with only small amounts of starchy carbs (mostly from oatmeal).

First, the good news: my workouts were pretty good—not sensational—but good. The pump from P-Slin was comparable to some NO supps I’ve taken. Now, the bad news: I gave it up after a week, as I found myself wanting to lay down and take a little nap 5–6 times a day. It didn’t feel like I was suffering from any hypoglycemic response—as long as I was moving around, I was fine. But I couldn’t sit for more than 30–40 minutes without losing focus: my eyelids would start to droop and my head would sag towards the keyboard. Since I write for a living, this was no good. All the extra carbs were doing me in, so the experiment came to an abrupt end.

Others have fared better: although there are some dissenters, the overall trend of the reviews I’ve seen have been positive. Naturally, very few of these report results as dramatic as the ones featured on the USP web site, which claim that testers gained an average of 7.3 lbs. of muscle and lost 5.4 lbs. in the first 14 days. Many users, however, seem to be satisfied with their purchases.

Anabolic Pump and P-Slin certainly represent an interesting innovation: they aren’t your typical bodybuilding supplements. While I feel that the results may be somewhat exaggerated, these supplements could conceivably help curb fat gains on a bulking cycle. As such they could be worth experimenting with. Hopefully, they’ll work better for you than they did for me. 😉

Author: elissa

Elissa is a former research associate with the University of California at Davis, and the author/co-author of over a dozen articles published in scientific journals. Currently a freelance writer and researcher, Elissa brings her multidisciplinary education and training to her writing on nutrition and supplements.

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