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Reflex Nutrition One Stop Xtreme


Now £34.96

Chocolate Perfection In Stock
Strawberries & Cream In Stock
Vanilla Ice Cream In Stock
Reflex Nutrition One Stop Xtreme


Now £57.95

Chocolate Perfection In Stock
Cookies & Cream In Stock
Strawberries & Cream In Stock
Vanilla In Stock
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Reflex Nutrition One Stop Xtreme

One Stop Xtreme is designed to outperform other muscle building formulas and is for people wanting to pack on mass fast

One Stop Xtreme is Reflex Nutrition’s most hardcore muscle building supplement in its 15 year history. Designed to outperform all other muscle building formula it is the product for people wanting to pack on mass fast. It is the only product to contain the exclusive Quattro protein blend with every single batch lab tested for protein content.

55g of Quattro time-release protein
Arguably the most sophisticated protein blend in existence that you won’t find in any other product. Quattro is unique to One Stop Xtreme, exclusively from Reflex Nutrition. It consists of three different types of whey protein in conjunction with pure undenatured micellar casein. Four of the best!

Contains organic & low GI sources of carbohydrates
The primary carbohydrate content of One Stop Xtreme is provided by a unique complex of organic oats and barley with naturally occurring vitamins, minerals and dietary fibre. Added to this is the designer low GI carbohydrate trehalose; this provides your body with a very stable long lasting form of carbohydrate that will help prevent gains in fat whilst also providing the increased energy that is needed to fuel intense training sessions.

Contains an added 3,000mg of mTOR anabolic L-leucine
Of all the essential amino acids the branched-chain amino acid L-leucine is the most potent. L-leucine is scientifically proven for its ability to initiate biological signalling via mTOR (mammalian target of rapamycin) - in simple terms it can trigger increased protein synthesis when combined with whey hydrolysate and carbohydrate taken after resistance exercise.

Every 145g serving provides a huge 10,500mg dose of BCAA’s
Because One Stop Xtreme contains such a potent complex of whey peptides and whey fractions it therefore contains naturally high levels of branched-chain amino acids. Just one serving provides 10,500mg of BCAA’s! Branched-chain amino acids are scientifically proven to increase protein synthesis, increase workout capacity and aid in recovery.

5,000mg of patent process Creapure creatine monohydrate
Nearly all of the scientific studies relating to increased muscular strength, increased power, increased endurance and increased lean body mass have one thing in common. They all used Creapure creatine monohydrate. That is because Creapure is recognised as the best quality creatine monohydrate available today, providing a patented solution to your strength and growth goals. Whilst other supplements contain different forms of creatine like creatine ethyl ester (CEE), none of these other forms have ever been proven to outperform Creapure creatine monohydrate.

Research proven levels of beta-alanine
The harder, more intensely you train, the greater performance and results. However, with intense training comes lactic acid, ammonia and acidity build up. Beta-alanine is a precursor to carnosine which helps to buffer acidity/pH changes within muscle tissue. Scientific studies have proven that beta-alanine decreases fatigue in athletes and increases total muscular output. Industry leading doses of 1,800mg beta-alanine are found in just 1 serving of One Stop Xtreme.

10,000mg of the most biologically available form of glutamine
10g of glutamine peptide, a potent source of glutamine, which is credited with anti-catabolic and immune support. Glutamine peptides are absorbed by the body more easily than normal L-glutamine. This is especially important in an all-in-one formula where protein and other amino acids will compete for absorption.

Contains a full complement of vitamins
100% of the RDA of vitamins which makes it unique in the all-in-one market.

Strength-boosting magnesium with testosterone-supporting zinc and avena sativa
One Stop Xtreme contains zinc monomethionine, the highest known quality form of zinc. This is instead of the cheaper, less easily absorbed zinc oxide. Avena sativa is included to support healthy testosterone levels. Magnesium, in the high quality form of magnesium citrate (instead of magnesium oxide) is included in the formula to help boost strength and energy production.

Contains stable probiotics, digestive enzymes and a bioavailability enhancer
LactoSpore probiotics are added for gut health and Digezyme digestive enzyme complex is added to help the body digest these performance ingredients more efficiently. Also included is BioPerine a patented and natural bioavailability enhancer to ensure your body gets maximum absorption of the nutrients contained in One Stop Xtreme.
Container Size: 2.03kg
Serving Size: 4.5 Scoops (145g)
Servings Per Container: 13
Container Size: 4.35kg
Serving Size: 4.5 Scoops (145g)
Servings Per Container: 30
Amount Per Serving:
Total Calories: 570
Protein: 55g
Total Carbohydrates: 72g
-Sugars: 9.6g
-Dietary Fibre: 3.9g
Total Fat: 6g
-Saturates: 3.6g
Sodium: 225mg

Xtreme Muscle & Strength: (31,300m)
Beta Alanine: 1,800mg
Creatine Mono’ (Creapure): 5,000mg
Glutamine Peptides: 10,000mg
Glycine: 2,500mg
BCAA’s: 10,500mg
L-Leucine (free form): 3,000mg
Taurine: 1,500mg

TestoFusion Stack: (657mg)
Avena Sativa: 500mg
Magnesium: 150mg
Zinc: 7.5mg

Vitamin A: 400μg
Vitamin D3: 7.5μg
Tocotrienols (DeltaGold): 7.5mg
Vitamin C: 100mg
Vitamin B1: 1.6mg
Vitamin B2: 1.6mg
Niacin: 9mg
Vitamin B6: 1.6mg
Folic Acid: 100μg
Vitamin B12: 1.2μg
Biotin: 80μg
Pantothenic Acid: 3mg
Potassium: 160mg
Calcium: 195mg
Phosphorus: 117mg
Iron: 2.3mg
Copper: 801μg
Selenium: 27μg
Chromium: 50μg
Choline: 100mg
Piperine (BioPerine): 5mg
Digestive Enzymes (Digezyme): 145mg
Probiotic Spores (LactoSpore): 145,000,000


Quattro Protein Blend (Ultra Filtered Whey Protein Concentrate & Cross Flow Micro Filtered Whey Protein Isolate, Hydrolysed Whey Protein (degree of hydrolysis 30%), Hydrolysed Whey Protein (degree of hydrolysis 4%), Milk Protein Concentrate), Low GI Carbohydrate Blend (Organic Oat Flour, Organic Barley Flour, Trehalose), Maltodextrin, Xtreme Muscle & Strength Stack (Beta-Alanine, Creatine Monohydrate (Creapure), Peptide-Bonded Glutamine (derived from Wheat Protein), Glycine, L-Leucine, Taurine), TestoFusion Stack (Avena Sativa, Magnesium Citrate, Zinc Monomethionine), Natural Colourings (Fat-Reduced Cocoa Powder (Chocolate and Banoffee varieties only), Betanin (Fruit Berry varieties only), Beta Carotene (Banoffee and Vanilla varieties only), Anthocyanin (Fruit Berry varieties only), Flavourings, Emulsifier (Soya Lecithin), Thickeners (Carboxymethyl Cellulose, Xanthan Gum), Ascorbic Acid (Vitamin C), L-Choline Bitartrate, Digezyme Digestive Enzyme Complex (Amylase, Cellulase, Lactase, Lipase & Neutral Protease), Artificial Sweeteners (Acesulfame K, Sucralose), Tocotrienols as DeltaGold (35% total Tocotrienols of which 84-95% Delta-Tocotrienols, 8-16% Gamma-Tocotrienols) obtained from Annatto, LactoSpore Probiotics (Bacillus Coagulans), Ferrous Bisglycinate, Niacin (Nicotinamide), Copper Aspartate, L-Selenomethionine (Selenium Select), Piperine Extract (Bioperine), Retinyl Acetate, Cholecalciferol, Calcium D-Pantothenate, Riboflavin, Thiamin Hydrochloride, Pyridoxine Hydrochloride, Chromium Picolinate, Folic Acid, D-Biotin, Methylcobalamin.

Mix 145g (approximately four and a half level 60ml measures) with 400ml water and mix thoroughly in a shaker cup or blender.

Daily serving: Take one serving mid morning between meals and one serving after your workout. On non training days take two servings, one mid morning between meals and one serving in the afternoon between meals. Do not exceed the stated dose.
Reviews (9)

"Following 12 months out from training, I have used this product alongside a consistent diet and have gained 14lbs in 4 weeks! Strength is gaining each session and will probably stick to chocolate flavour again. Yes will be buying again!"

Posted by Hamza  (13th June 2014)


"I am really surprise with the quality of One Stop Extreme. I have been being used different supplements for a past few years depends on my period goals. This is the best supplements if you want to get weights and size. I got 3.5 kilo within first week and technically creatine doesn't show its affect in first week so I think I will work even better in the next few weeks"

Posted by Sam Khoie  (12th April 2014)


"Just got a bag of this in chocolate flavor, and i will admit that it tastes really nice compared to the last product i was using. i haven't used it in action yet but when i do i will update my post."

Posted by Osinachi Igwe  (24th January 2014)


"This product is awesome. I bought 2 banofees and i cant say anything against it! The mass you get after this with right things is awesome. When i will need more allinone product i ll buy only ONE STOP XTREME."

Posted by Adam Kaplár  (10th October 2013)


"this is one of the best all in ones on the market .i have had tons of them it does the job .its a must"

Posted by craig johnson  (4th October 2013)

Write a Review
Q Can this be mixed with Milk or Soya Milk?

Can be mixed with both.

Q Hi Im 5'10 and would say im skinny fat build but have got down to 14%-16% bf Would i be best trying to build with osx to add muscle Thanks

Yes definitely. Building lean muscle mass will make you appear more defined anyway by causing the skin to become tighter around the muscle belly.

Q Hi is one stop extreme the best all in on product in the market ?

One stop extreme has a very impressive formula and is considered as one of the best selling all in ones on the market. You will not be disappointed with this product.

Q Hi, I was wondering if this product would help me to gain lean muscle with minimal fat gains like an all in one product or is it more of a weight gain product? Also could you recommend a good quality lean gainer that is good value for money? Thanks

One stop extreme is a great product for promoting muscle mass but tis product dose pack as many calories as most weight gainers do so if you’re looking to keep the body fat low and focus more on lean mass gains then you could look at either, taking half the serving which would work just as well or trying a product like Phd Synergy Iso7 which is also an all-in-one product put quite low carb.

Q Hi, I'm looking for a bit of advise. I've used Reflex One Stop Xtreme before and seen good, steady results whilst stacking with Superpump Max pre-workout and Waxy maize + Pepto pro + Creapure post workout. I'm 5'11", 83kgs and about to begin another creatine cycle. I'd like to know whether I should stick with my previous stack, or would I see greater muscle mass gains using or Pure Protein IGF-1, with either Superpump Max or Jack3d pre workout?

“The best stack” is the one that works best for you. Every individual is different so trial and error is the only proper way of finding out what the best stack is for you. A rule of thumb is “if it’s not broken, don’t fix it” but it is always a good idea to try different products. Cell-Tech stacked with Nitro- Tech is known for being a very beneficial stack to take but if you looking for increased mass gains then maybe look at Mass-Tech in place of nitro-tech as the extra calories will help you create muscle mass at a faster rate.

Q Hi,i take this as 1 serving once a day to maintain muscle and not gain fat. Is this the right product for me? Thax

One stop extreme is a fantastic well formulated all-in-one product which is perfect for and set goal.

Q how many of them should i take from this product? it is a 4.3 kg and it is for 2 weeks enough.. i just wanted to know how many of them enough to get ripped i am 70 kg.. thanks.

If you are looking to get ripped only take on of these and ensure that you food based around this product is high in protein and low in carbohydrates and the food that you are eating is of good quality to ensure you are getting the most from your training.

Q I'm 20 years old. I weigh 72 kg and my height is 5 ft 11". Would this product be ideal for me to gain lean muscle mass? If not what do you recommend? Also what are the side effects? Will my face get fat?

Provided that you are following an otherwise sensible diet and have the appropriate exercise regime put in place, you will begin to gain weight, consisting mostly of lean muscle mass. If you are inactive, calories consumed in excess to your energy requirements will be stored as fat. If you are underweight, however, gaining a proportion of body fat, gradually and sensibly is to be advocated. As for facial appearance, this will largely depend upon genetics; if you put on weight, your face is likely to 'fill-out' so to speak as weight does not accumulate in specific areas - it is gained all over the body. Just as a person may appear gaunt if they lose too much weight, the opposite is true, and their face will take on a fuller appearance. I hope the above information addresses your query.

Q which is the most popular i.e nicest tasting flavour?

Chocolate, followed by strawberry are most popular.

Q I don't see mono creatine on the nutrition list, I assume this is in there, but how much in each serving?

It contains 10g of creatine monohydrate (creapure) per 150g serving.

Q What are the macros for one scoop? Thanks.

Hi Raphael, Just divide the totals by 4.5 scoops... Calories: 127 Protein: 12g Carbs: 16g Fat: 1g

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