MD2 Meltdown is VPX Sports’ most recent stimulant fat-burner. It contains several highly effective fat-burning ingredients at effective doses. We wouldn’t recommend it for the stimulant-sensitive…[Skip to the Bottom Line]
Caffeine is the most widely consumed psychoactive substance in the world, and is a well-established ergogenic aid. Caffeine consumption causes an increase in Catecholamines (Adrenaline, Noradrenaline, and Dopamine), which tend to increase focus, concentration, and perceived energy while simultaneously promoting lipolysis. However, the weight loss effects of caffeine tend to fade with prolonged use, so it does not appear as though caffeine is a long-term effective fat burner. While caffeine’s weight loss potential is negligible, it increases focus and perceived energy in most people, which generally leads to more intense workouts (thus burning more fat), and may potentiate the action of other stimulants like yohimbine.
Theacrine is an alkaloid that is synthesized from caffeine in plants, and found along-side it in Kucha tea. Because of the chemical similarities it shares with caffeine, its effects are similar as evidenced in a 2012 study in which Theacrine injections significantly increased locomotion in rats. Interestingly, the researchers in this study noted no trend toward tolerance even after 7 days, indicating the effects of Threanine remain potent longer than caffeine. Unfortunately, there are studies upon which to draw conclusions (or even inferences) regarding any potential fat-burning effect of Theacrine, though it may potentiate the effects of caffeine.
Evodiamine is a plant extract which appears to mimic the thermogenic effects of Capsaicin in rats. However, no human studies have been published at this time testing the effects of the extract on humans. Due to the lack of human studies available, we cannot determine with any considerable degree of certainty the efficacy of Evodiamine. It seems plausible that it is similar to Capsaicin in terms of effect.
N-Methyl-Tyramine (NMT) is a Tyramine which, as mentioned above, can inhibit the reuptake of monoamines (specifically Noradrenaline), thereby amplifying and/or extending the effects of Noradrenaline releasing stimulants such as Caffeine. VPX Sports does not disclose the exact dose of NMT present in MD2 Meltdown but given only 20-30mg would be needed, there is no reason to suspect a less than optimal dose.
Yohimbe (Corynanthe yohimbe) contains several active alkaloids with similar structures and characteristics: Yohimbine HCl, 11-hydroxy yohimbine, and alpha-yohimbine. Each of these compounds is discussed below…
Yohimbine, which acts as an alpha-2 receptor antagonist, meaning it inhibits the receptor responsible for blocking lipolysis (fat burning). By blocking the action of this receptor Yohimbine essentially “leaves the gates open” for lipolysis to occur. A 2006 study showed that while there were no increases in strength, supplementation induced fat loss in athletes (soccer players). As previously stated, Yohimbine directly acts on alpha-2 receptor, but it’s fat loss capabilities may also be magnified by its ability to increase the catecholamine neurotransmitters adrenaline and noradrenaline which in turn induce lipolysis. As mentioned above, an increase in these neurotransmitters may result in increased focus and workout intensity.
11-Hydroxy yohimbine is quickly becoming popular as a fat-burner additive because it has a longer half-life than Yohimbine HCl. A 1999 study, published in the “European Journal of Pharmaceutical Sciences”, found that 11-Hydroxy yohimbine had a half-life roughly four times that of standard Yohimbine. Though there is very little research directly comparing these different alkaloids, 11-hydroxy yohimbine appears inhibit alpha-adrenergic receptors with similar potency as yohimbine HCl.
Rauwolscine (also known as alpha-yohimbine) is what is known as a ‘stereoisomer’ of yohimbine, meaning it is chemically similar in structure. Because of this similarity, Rauwolscine produces similar effects, although perhaps to a milder degree. It is common to find all three of these alkaloids together in fat-burning supplements because they can all be extracted from Corynanthe yohimbe.
THE BOTTOM LINE:
MD2 is a purely stimulant-based fat-burner containing scientifically validated ingredients like the Yohimbe alkaloids, as well as less-researched compounds such as 4-amino-2-methylpentane citrate. That being said, the net effect of caffeine and yohimbe alone is likely to be weight loss so Theacrine and 4-amino-2-methylpentane citrate could further magnify that effect or, at the very least, provide increased energy and focus in the gym. Individuals who are highly sensitive to stimulants should stay far away from MD2, but for those who can tolerate these types of stims, the formula may result in significant fat loss (when combined with exercise of course). At about 75 cents/serving, MD2 is priced on the lower end as compared to the average stim-based fat burner which tend to be over $1/serving.
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