PepTest Bulk Review

PepTest Bulk is MAN Sports’ most recent innovation which essentially combines the focus/energy enhancement of a pre-workout with the test-boosting properties of D-Aspartic Acid…

MAN Sports PepTest Bulk



Acetyl-L-Carnitine (ALCAR) has been pretty extensively researched for a variety of purposes relating to physical performance and cognition but, in the context of PepTest Bulk, we’ll focus on the cognitive effects.

A 2001 study from the “Journal of Neuroscience Research” found that ALCAR supplementation was able to improve indications of learning in older mice at a dose that would translate into a 200lb human consuming about 1g.

In humans, ALCAR has been demonstrated to reduce the severity of cognitive decline in elderly dementia patients, as well as in older subjects with general cognitive decline (not any particular cognitive disease).

Unfortunately, studies regarding the effects of ALCAR in healthy individuals are limited, and at this time there is insufficient evidence to suggest it is particularly effective as a nootropic. That said, clearly ALCAR possess pro-cognitive properties so it makes sense in the context of PepTest Bulk.


Caffeine is a well-established ergogenic aid, oral consumption of which triggers the release of Catcholamines (Noradrenaline, Dopamine, Adrenaline, etc.), generally inducing a state of increased alertness, focus, and perceived energy.

Additionally, Caffeine can enhance calcium-ion release in muscle tissue, which directly increases muscle contraction force. Rather than discuss dozens of studies, we’ll leave it at this: Caffeine is an extremely effective ergogenic aid, though tolerance build-up is certainly an issue to keep in mind.

MAN lists the amount of Caffeine Anhydrous in PepTest Bulk at 200mg per serving, enough to make the average individual feel noticeably more alert and focused, especially in combination with several of the other ingredients in PepTest Bulk.


Tyrosine is a non-essential amino acid (the body can produce it from Phenylalanine) which serves a precursor to Dopamine (by first being converted into L-Dopa) and Noradrenaline.

Because of this relationship, Tyrosine is alleged to increase levels of these neurotransmitters, which would theoretically lead to performance enhancement. However, research has demonstrated that Tyrosine cannot outright raise Dopamine or Noradrenaline levels upon ingestion, though it can help maintain optimal levels when depletion might otherwise occur.

Upon ingestion, Tyrosine forms substrate pool, which can then be drawn from when an acute stressor (exercise, cold exposure, etc.) causes a temporary depletion of Dopamine/Noradrenaline. For this reason, Tyrosine can be useful for maintaining cognitive function during stressful activity.

PepTest Bulk contains an undisclosed amount of Tyrosine, but we’d estimate no more than 200mg or so.


Green Tea contains a catechin known as Epigallocatechin gallate (EGCG) and is generally standardized to a specific concentration. EGCG is a moderately potent anti-oxidant, but can also inhibit Catechol-O-Methyl Transferase (COMT), the enzyme responsible for the degradation of catecholamine neurotransmitters (Noradrenaline, Dopamine, etc.).

By inhibiting COMT, EGCG can potoentiate the effects of other stimulants such as Caffeine and Higenamine, and functions similarly to Hordenine as well. In the context of PepTest Bulk, EGCG may indeed be effective for enhancing focus and energy.


Nelumbo Nucifera (NN), sometimes referred to as Indian Lotus, is a flowering plant which has been shown to have anti-obesity effects in mice. The lipolytic effects of Nelumbo Nucifera are primarily attributed to the Higenamine, although there are other compounds which may potentiate these effects. Higenamine is a Beta(2) Adrenergic Agonist (same mechanism as Ephedra), meaning it stimulates the Beta(2) Adrenergic Receptors which initiate fat-burning.

MAN doesn’t tell us exactly how much Higenamine is present in PepTest Bulk, but no optimal dose has been established for humans anyway, so it doesn’t really matter.


Hordenine is included in many pre-workout supplements and fat-burners because of its ability to amplify the effects of Caffeine. In vitro and animal studies indicate that its primary mechanism of action is via Momoamine Oxidase inhibition, with oral doses being shown to augment Noradrenaline-induced muscle contraction while not directly inducing contractions itself.

So, rather than acting as a stand-alone stimulant, Hordenine can amplify/extend the effects of other stimulants by blocking the reuptake of Noradrenaline (and other Monoamines).

MAN Sports does not disclose the amount of Hordenine present in PepTest Bulk but it doesn’t take much to be effective. Certainly no reason to suspect a less-than-effective dose here.


MAN Sports makes no mention of Cocoa extract in any of the PepTest Bulk literature we’ve reviewed, so we’re not really sure what the proposed benefit is in this instance. Generally speaking, Cocoa is standardized for xanthines such as Theobromine and Theophylline.


Sceletium tortuosum, also known as Kanna, is an herb mostly indigenous to South Africa which has a long history of use as a mood elevator/anxiolytic. Kanna contains two types of alkaloids, mesembrine tortuosamine, which are alleged to convey the psychoactive effects.

A 2011 study published in the “Journal of Ethnopharmacology” found that Sceletium tortuosum extract had limited anxiolytic effects in rats subjected to psychological stress (in the form of restraint). While no mechanism of action has been established, the results of the study indicated that the herb does not act as a serotonin reuptake inhibitor (SSRI).

MAN fans should be familiar with Sceletium tortuosum, as the brand has used it in NOOPump as well. It’s unclear what dose is present in PepTest Bulk but, given that no “optimal dose” exists, it doesn’t really matter anyway.


Coleus Forskohlii is generally standardized for the active component, Forskolin (sometimes spelled Forskohlin), which has implications for both weight-loss and increasing Testosterone. Forskohlin works by increasing Cyclic Adenosine Monophosphat (cAMP), a signaling molecule which, when elevated, can induce a wide variety of physiological changes including increased Tesetosterone, increased lean body mass, and decreased fat mass.

A 2005 study, published in “Obesity Research”, found that Forskohlin (25mg/day for 12 weeks) increased Testosterone (total test increased 16%, free test increased 3.4%) and favorably influenced body composition in obese men.

Though the effects of Forskohlin on Testosterone levels in humans have not been studied extensively, Forskohlin is quite reliable at increasing cAMP, and cAMP is quite reliable at increasing Testosterone. So ultimately, Forskohlin possesses a sound mechanism by which it can positively influence Testosterone levels in humans.

MAN Sports does not list the exact dose of Coleus Forskohlii present in PepTest Bulk, but given that this particular form is standardized for 95% Forskohlin, it would only take 25-30mg to be effective for boosting Testosterone.


D-Aspartic Acid has become extremely popular as a Test-booster in recent years, with research suggesting it is indeed effective, at least in the short term.

A 2012 study from “Advances in Sexual Medicine”, the subjects of which were infertile men (initially low Testosterone) found that 2.66g of D-Aspartic Acid was able to significantly increase Testosterone levels when measured after 90 days of supplementation. These results were in-line with those of an earlier study from 2009 in which D-Aspartic Acid supplementation raised Testosterone by 42% after 12 days in healthy men (initially normal Testosterone).

However, a 2013 study published in “Nutrition Research” found that athletes who supplemented with D-Aspartic Acid for 28 days showed no difference in testosterone levels.

The researchers in the failed study noted abnormally high levels of D-Aspartate Oxidase, the enzyme which degrades D-Aspartic Acid, indicating that prolonged supplementation in individuals with healthy Testosterone levels may cause “negative feedback”.

PepTest Bulk contains a clinically effective 3120mg dose of D-Aspartic Acid per serving.


In the past few years, Agmatine has gone from a rare ingredient to pre-workout staple, though it remains seriously under-researched relative to other popular pre-workout ingredients. Agmatine has been demonstrated to up-regulate Endothelial Nitric Oxide (eNOS), sometimes referred to as the “good” NOS, while inhibiting the other NOS enzymes (the “bad” NOS) in vitro, but human studies are non-existent.

While Agmatine is commonly touted to increase Nitric Oxide, there is preliminary evidence which indicates it can induce the secretion of Luteinizing Hormone (LH), which can in turn trigger Testosterone production. A 1995 study found that rats treated with Agmatine experienced increased LH secretion in a dose-dependent manner.

MAN Sports is no stranger to Agmatine (see NOOPump) and has elected to use an industry standard 500mg dose for the PepTest Bulk formula.


PepTest Bulk is yet another innovative pre-workout with a twist from the folks at MAN Sports. The cognitive/focus effects will be quite apparent to the average individual, and with a clinical dose of DAA per serving, users may experience increases in Testosterone as well. At just over $1 per serving, PepTest Bulk is fairly priced, and is worth a shot for anyone looking for a PWO/Test-Booster combination.

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