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HR Labs Defib redefines the pre-workout category. A bold statement for sure but one that we feel is entirely justified.

HR Labs Defib research-driven formula utilises high doses of effective ingredients, is fully transparent and highly effective.

Citrulline Malate

For its ability to increase Nitric Oxide (NO) production, subsequently increasing blood flow whilst also delaying fatigue and reducing muscle soreness post workout. Citrulline increases levels of Arginine, a precursor to NO, in the blood more effectively than supplemental Arginine, which is why it is now considered to be infinitely superior to the one-time Pre-Workout staple. It’s multiple benefits as both a performance aid and for health in general mean its inclusion in DEFIB is a no brainer.

Beta Alanine

For its ability to improve performance, reducing lactic acid and offsetting fatigue during intense exercise – this is primarily down to the significant increase in Carnosine levels that can be attributed to REGULAR supplementation. Beta Alanine also has purported beneficial effects on Cognitive function in the short term and that impossible to ignore nervous system response.

Betaine Anhydrous

A methyl donor, for its ability to increase energy production, elevate protein synthesis and increase NO production. It also assists with cell hydration which can improve performance and reduce muscular fatigue.


A powerful Nootropic, for its effect on cognitive function, improving mental alertness and focus and enhancing mood.


for its ability to facilitate the production of the neurotransmitter GABA and the subsequent calming effects associated with this, helping to offset the negative side of caffeine & stimulant consumption – clean energy is king! No crashes or post training come downs on our watch.

Peak O2™

An Adaptogenic Mushroom complex, rich in antioxidants. In clinical trials it was proven to increase the body’s ability to uptake oxygen and use it more efficiently. It was also proven to have a significant impact on power output. In short Peak O2 enables you to train harder, for longer!


A methylliberine, a purine alkaloid found in the kucha tea leaf. Structurally it is very similar to its more famous cousin, theacrine (aka TeaCrine®). But is believed to take effect far quicker. Like theacrine, it enhance mood and focus by activating dopamine receptors and other key neurotransmitters all without elevating heart rate or blood pressure. Ongoing studies suggest that Dynamine™ may work synergistically to enhance the beneficial effects of Caffeine.

What are the key features of this pre workout?

Research-driven formula
High doses of effective ingredients
Active ingredients
L-Theanine for insane mental focus
40 servings
HR Labs Defib is a highly dosed, research driven pre-workout formulated for advanced trainers. Please consider your own tolerance levels prior to use. We recommend taking one scoop (11.5g) mixed with 250 – 350ml of water 20 – 30 minutes prior to training. Advanced users may benefit from taking two scoops (23g) in the same way. Optimal dosages of active ingredients attained at two scoops. Do not exceed more than 2 servings in any 24hr period, seriously. Do not use within 5hrs of intended sleep.

Additional information

Weight .460 kg

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