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USN Muscle Fuel STS


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USN Muscle Fuel STS

USN Muscle Fuel STS meal replacement protein shake is available at lowest price in the UK at We offer free delivery on all of the top bodybuilding and sports nutrition supplements to UK Mainland and the cheapest rates right across Europe! Check out our special offers page for huge discounts on the biggest brands!

USN Muscle Fuel STS

Get a Tornado Shaker Free when you spend £50 or more - Whilst Stock Lasts!

Get a Tornado Shaker Free when you spend £50 or more - Whilst Stock Lasts!

Get a Tornado Shaker Free when you spend £50 or more - Whilst Stock Lasts!

USN's Muscle Fuel is an advanced engineered meal replacement formula that is designed for active people who demand the benefits of top quality proteins, complex carbohydrates, and nutrients for optimum health and muscle performance. Studies suggest that using a variety of protein substrates may work best for improving protein synthesis and overall health. Unlike other meal replacement formulas, USN's Muscle Fuel is low in sugar and also offers a variety of anti-catabolic amino acids. This unique formula combines high biological value proteins with a very low glycemic index carbohydrate to build and repair muscle tissue while balancing nitrogen levels during workouts.

Just enough carbohydrates are used to fuel your workout, replenish depleted glycogen and push your metabolism into hyper drive. It is designed to pack muscle on even the hardest of the hard gainers with optimal protein-to-carb ratio and a level of quality protein that guarantees an anabolic environment for muscle growth and performance. USN's Muscle Fuel is a complete meal that is very low in fat, great tasting and easily digestible.
Container Size: 2000g
Serving Size: 2 scoops (110g)
Servings Per Container: 18

Container Size: 5000g
Serving Size: 2 scoops (110g)
Servings Per Container: 45

Amount Per Serving:

Total Calories: 408
Protein: 44g
Total Carbohydrates: 49g
-Sugars: 4.4g
-Dietary Fiber: 3.3g
Fat: 4g
-Saturates: 1.9g
Vitamin A (retinol): 267µg
Vitamin D (cholecalciferol): 3.3µg
Vitamin E (d-alpha-tocopherl): 8.8mg
Vitamin C (ascorbic acid: 20mg
Vitamin B1 (thiamin mononitrate): 0.46mg
Vitamin B2 (riboflavin): 0.56mg
Niacin (nicotinamide): 6mg
Vitamin B6 (pyridoxine-5-phosphate): 0.66mg
Folic Acid (pteroylmonoglumatic acid): 67mg
Vitamin B12 (cyanocobalamin): 2.66mg
Biotin (d-biotin): 0.1mg
Pantothenic Acid (d-pantothenate, calcium): 3.3mg
Calcium (from natural milk source): 331mg
Sodium: 330mg
Phosphorus: 460mg
Magnesium (magnesium oxide): 49.5mg
Potassium: 748mg


Whey Protein isolate and concentrate, calcium caseinate, soy protein isolate, egg albumin, lactase enzymes, MCT oil (medium chain tri-glycerides), stabiliser (cellulose gum), flavouring, calcium (from natural milk source), l-glutamine, fructooligosaccharides (FOS), magnesium oxide, vitamin C (l-ascorbic acid), niacin (nicotinamide), vitamin E (d-alpha tocopherol), pantothenic acid, (d-pantothenate, calcium), vitamin B6 (pyridoxine-5-phosphate), vitamin B2(riboflavin), vitamin B1 (thiamin mononitrate), biotin (d-biotin), vitamin A (retinol), folic acid, vitamin D (cholecalciferol), vitamin B12 (cyanocobalamin), sweetener (sucralose)

Please Note:
Nutritional facts and ingredients may vary slightly between flavours.
As a dietary supplement, add two rounded scoops to 400ml of cold water. Use a blender or a hand held shaker and mix for about 30 seconds. Have 2 to 3 servings daily. (Servings may be halved) For even higher calories in the form of extra protein and carbs you could use fat free milk instead of water.
Reviews (29)

"just started on this stuff and its great, meal replacement ,great taste, and feeling the benefits already."

Posted by anthony  (5th March 2015)


"Been on this for over 6 months and the gains are fantastic!

Ordered for the first time on Tuesday afternoon and it was with me Wednesday AM - Super quick delivery! Will definitely use again!"

Posted by Mark  (21st October 2014)


"Been on many proteins and this one is good. Good taste, good price. Great delivery too"

Posted by chris  (22nd September 2014)


"Very quick delivery. Good taste with coco milk. I will order again and again."

Posted by Arpad  (28th June 2014)


"this product is excellent my son who has crohns can maintain his weight and feels so much better on it"

Posted by June Senior  (16th October 2013)

Write a Review
Q Hi I asked if the chocolate flavour was suitable for vegeterians and I was told that its not but I had a look at the USN Website and on there it says it is suitable for vegeterians. So I'm a bit confused as to which it is. Can you clarify please?

Good Afternoon, Apologies for the confusion - I checked the nutritional information on the label of said product, and it did not state anywhere that it was suitable for vegetarians. However, you are quite right - their website states that the product is suitable for vegetarians. Since we are stockists of a great number of products, it is very difficult for us to ascertain whether specific items are suitable for vegetarians 100% of the time, as they vary so much between brands. I would advocate following the guidelines given on a specific company's website - if the product is advertised as suitable for vegetarians, then it invariably will be. If you require any further clarification, I would advise contacting USN directly via the company's email address.

Q Hi im 18 years old , 5ft 6 and only 54kg ,im in the gym 5 times a week and im looking for a good meal replacement to help me gain size & mass , i find it hard to gain mass with just my current nutrition ,so would this be a good choice to accompany my current nutrition for maximum size? or could you point me in the right directinon of another product you sell that would help me out ? many thanks

You need a weight gainer product and creatine in addition to eating your meals. Your best choices are: 1) Mutant Mass - 2 scoops twice per day with a level teaspoon of creatine monohydrate added or a creatine tablet 2) Muscle Fuel Anabolic - 2-3 scoops twice daily (contains creatine) 3) Mass-Tech - 3-4 scoops twice daily (contains creatine).

Q Hi just wanted to ask if the chocolate flavour is suitable for vegetarians Thanx

I have checked the label and I am afraid that it does not state that Muscle Fuel STS is suitable for vegetarians, therefore it is likely to contain animal-derived ingredients, or be manufactured in an environment which uses said ingredients.

Q hiya i am looking to take up boxing i want to prevent catabolism as much as possible with out adding extra mass, would fuel sts be good enough to prevent catabolism or would fuel anabolic be better?

Anabolic is a more potent muscle-builder and has more calories but will also help you resist losing muscle better. STS has fewer calories and is less likely to bulk you up but will also help you avoid muscle loss. If your activity level and metabolic rate are high enough, you shouldn't gain extra mass on either but if not, go with the STS.

Q I do mma training and boxing and iam goin to start useing 'USN muscle fuel sts' and i was wondering Whats the best diet to have while on this

Unless you're using this to replace a meal, to improve performance and power, you'd be better off using muscle fuel anabolic (as it has creatine). If you need to lose weight/fat, use PhD Synergy Iso-7. Diet wise, this depends totally upon your goals - do you want to gain or lose weight?

Q I have recently purchased a tub of usn muscle fuel sts and was wondering does it have creatine in it or not, it states it has creatine monohydrate and other ingredients in a description about what makes the product so good (on the tub), but when i look at the nutritional information there is no mention of it and the amounts at which it is present. Ive been online to try and see, but it seems there is no mention of it being contained in the product at all! Whats going on?

Muscle Fuel STS doesn't contain creatine and it isn't advertised as having it (that we're aware of). I think you've confused it with Muscle Fuel Anabolic, which does have creatine. Check out the Tropicana "ALL NEW Article Section" - - which contains the best information on supplements, written by experienced, qualified industry experts!

Q I train 4/5x a week weight work and play football twice a week, I'm currently 15% Body fat at 11.5st. I'm trying to keep lean whilst gaining size/definition. I've been taking this for about four months, would you recommend I continue or could you suggest a more suited product?

In order to gain size you need to over eat your daily intake of calories by around 500+. To decrease body fat you need to under eat you daily intake of calories by 500+. With that said, you cant build muscle and be lean at the same time. Muscle fuel STS is a meal replacement formula, so ideal if going long periods with out eating. Firstly decide what is more important, Gaining Mass or staying lean. A low fat/Carb protein stacked with a quality fat burner is what everyone generally goes for when dieting to lose fat. Weight gainers are there to help meet your calorie needs and gain good clean muscle mass. PVL Mutant mass or MuscleTech Mass-Tech tend to be amongst the favourites.

Q I want to loose weight.i want to burn fat without loosing my mass, can i use this product? probably i will take also fat burners with it and make more cardio exercises .

Yes you can use this product but keep in mind to lose weight you need to be in a calorie deficit of around 500-1000 calories per day depending on your body type. So be sure not to take in more calories than you need.

Q what is the main difference between this product and USN pure protein?and which is the best to take to bulk up?

STS is a higher calorie and higher carb meal replacement, so it also contains vitamins and minerals as would be found in a nutritious meal. Pure Protein is mostly protein (so it has much fewer calories and carbohydrates) and no additional vitamins and minerals (besides those that occur naturally in the proteins).

Q As this is a meal replacment shake if i was to use the product as my sole source of food would it help me loose weight or would i gain it due to it building muscle mass?? By the way i dont exercise other than walking

If you do not exercise you will not build muscle mass using this product also losing weight is all down to being in a calorie deficit which is below your daily maintenance level. We recommend eating healthy small meals every 3hrs (A shake can be a meal) 4-6 times per day to keep metabolism high and burn more calories.

Q Hello I have been taking this product for more than a month now and have seen improvements in mass. But I was told from a lot of people that this product was fake as USN have been mixing all sorts in it to save costs.

No, we can assure you it's not a fake product and USN's quality of whey protein and supplements is of the highest order. The results you've seen will be that of a good diet, training programme and good supplementation.

Q Hello, I am 14 and weigh 57kg. I am a competitive cyclist and need to gain weight and muscle. I am after the Muscle Fuel Sts. After a ride I am never hungery and I find it very hard to eat. Will this drink save me from eating a meal?

Yes, this would be a perfect meal replacement as it is very nutrionally balanced and dense, which will aid in your recovery from your cycling. If necessary this can be used more than once per day as well, however we advocate that this supplements your dietary needs, not replaces them.

Q hi can u use this products as pre and post workout

Yes. Consume 1hr 30 mins pre workout and immediately post workout.

Q hi how does this product differ from maximuscles progain. Which one would you recommend from the two because i always hear negative feedback from maximuscle products. can you please help.

Maximuscle products are good they just don't always get the best feedback on taste and they are quite a bit more expensive than other similar products. STS is higher protein, lower carb and slightly less calories so would be more of a "lean gainer", whereas Promax is more of a weight gainer - although a low-calorie one. so your decision depends upon your goals, how easily you put on muscle and how easily you gain fat.

Q Hi I have recently started mixed martial arts. What product is the best to lose weight and gain muscle

Calorie controlled diets are important when trying to lose body-fat and gain muscle. A lean mass gaining all in one would be ideal like Muscle fuel anabolic or Phd Synergy Iso-7

Q Hi i'm a lady aged 32 and weigh about 45kgs and i'd like to gain weight. Please tell me if this product is good for me to take inorder to gain the weight i require. I donot exercise though, just walk. Thanx.

In order to gain weight you simply need to consume around 500 calories more a day than you are burning. This product is a great meal replacement and will help you steadily gain weight if your diet is high enough in healthy calories. If you find you are not gaining weight then try looking at USN Muscle fuel mass as this will contain more calories. We always recommend a healthy diet and training routine when using sport supplements.

Q hi im 20 weight 55 kg i want to buy a 5 kg muscle fuel anabolic so if i use da whole 5kg how many kg em i going to gain

Hello, It's a question I can not answer as there are a number of variables to take into consideration, i.e Diet, metabolism, training type/intensity. I wish I could tell you! Sorry

Q Hi where are the carbs in the ingredients list? I assume it's fructose?

Maltodextrin is the primary carb source

Q Hi, I am 29, 85 kgs , 5.11 hgt I got 5kgs of Muscle Fuel STS recommended to me by my trainer . I would like to gain muscles a lean muscular body and lose fat mass will this product be very helpful?

Yes this product will help you towards your goal providing your diet also matches your nutritional needs.

Q Hi. I am 22 years old and I weigh 68 kgs. I started gyming a month ago. I want to gain size. What product do you suggest I take? Muscle Fuel STS or whey protein, or is there anything else you suggest Thank you for your assistance

Ideally you would want to cover all bases, we consider a good BCAA, Creatine, L-Glutamine product with a whey protein a good base to start with regardless of your goal.

Q hy irecently just bought a pack of USN muscle fuel STS will this suppliment help me on height increase? or which supliment helps on height increase?

There is nothing you can do to increase your height if you are of adult age, have undergone puberty and therefore, reached your full growth potential. Your height is largely determined by your genetics.

Q i am 15 years old, can i use muscle fuel sts?

Yes, this is simply a high-protein, meal replacement product. It's just a convenient, high-quality source of food to support fat loss and muscle gains.

Q i have started using muscle fuel can i combine it with creatine???

Yes, absolutely.

Q i really want to lose weight look ripped, do you suggest that this product can do the trick?

We would recommend you use a product that contains fat burning ingredient to help speed up your metabolic rate so that you can burn calories more effectively. USN Diet fuel would be perfect and look to stack this with Grenade fat burner.

Q I was curious in regards to flavors. An option is "variety", what does this mean? Is it that you get all 3 other flavors separate in the tub?

The variety tub will have 3 separate bags inside. One of each flavour.

Q i weigh about 258 pounds and am all ready in shape but i want to start using muscle fuel sts usn, but am worried that it may make me look fat than usual. is it fine for me to use it and how should i use it cause i realy like this product or will it just waste my money.pliz e-mail back.

If you are using this product to help supplement a meal or in place of a meal then this is fine but what you must understand is this, adjusting your diet to accommodate for the extra calories is essential. Even though it’s not extremely high carb you could still potentially gain weight using this product if you are not aware of your own daily calorie needs for the goal you are trying to achieve.

Q I'm 22yrs old 1.75m I weight 72kg I recently bought the usn muscle fuel sts product as I am looking to gain 10kg how long will it take me. I am an active person I need to gain the weight for rugby.

That all depends on your nutritional intake, training regime, sleep and genetics. We cannot definitively say that you will gain X amount of weight in a certain time frame however if you are new to weight training then your weight could rise quickly if all areas are executed well.

Q Im 15 and i am looking for Muscle gains . Im thinking of buying Either STS or MUscle Fuel mass . I cannot decide between the two. Also would stacking it with PURE GLATAMINE be wise as it already has ?

Go for the mass, as the STS is more of a meal replacement. At your age you probably need CALORIES! You can always add more glutamine up to 5 to 10 grams per day but it can get expensive, so depenes upon your £!

Q Is this better than the 100% whey gold shake? I am 25 and want to put on muscle and currently training 5 days a week. Which is the better shake?

It's a completely different product. The Muscle fuel STS is a meal replacement, the 100% Gold Standard whey from optimum is pure protein. If you are looking to build muscle the STS is the better option as it contains carbs.

Q Is this product gluten free?

Product label does not list Gluten in their allergy information, so we'd presume it would be fine however we'd recommend that you contact USN direct to find out if it is completely free from Gluten

Q is this product prohibited in the competative sporting world?

We believe not but this all depends on your organisation and what they class as banned substances or ingredients.

Q Really interested in this product but does this product contain gluten?

Hello, Gluten is not listed under the allergen information, but equally, it is not stated that the product is gluten free, either. For this reason, you may wish to instead try Cellucor Cor-Performance Whey, which is definitely gluten-free.

Q What are the benefits of using this product with usn muscle fuel anabolic, what is the difference between them?

Muscle fuel STS is more of a meal replacement formula which contains a reasonable amount of calories for what you would find in a healthy meal of protein, fats, carbs and multivitamins. Muscle fuel Anabolic is an all-in-one product with a high calorie content which is great for increasing size and strength and promoting muscle growth. This product also contains creatine for extra muscle building results. Both products can be stacked together if needed.

Q would you recommend this for a 16 year old?

This product is basically a meal replacement product - so protein + moderate carbs and fats, with vitamins and minerals. So no problem if used by a 16-yr old.

Q Should this product be taken as a meal replacement or a supplement to your diet? Goal is to shred body fat and tone, body fat currently about 18-20%.

  Muscle Fuel STS falls into the ‘meal replacement’ category, owing to its nutrient profile. It is designed for those individuals who are particularly busy and require a product that makes following a nutritionally sound eating plan more convenient for them; those who tend to skip meals due to a demanding lifestyle are at risk of losing valuable muscle mass, or being unable to attain the physique they desire. It is fine to use Muscle Fuel STS as a pre/post-workout supplement, or between meals, if you already eat a balanced diet and you are looking to gain lean mass. If used in this way, approximately two servings daily (as required) should be sufficient. I hope this answers your question. 

Q I work long hours so I find it difficult to go to the gym during the week and do a lot of resistance training at weekends. I carry weight on the belly but am otherwise lean. I'd like to lose my belly and build muscle mass. Will this product help me ? Thanks

Yes, if you used 1-2 servings per day in place of meals, then you would likely lower your daily calorie intake and increase your protein intake, which would together help to support fat loss and muscle gains and recovery.

Q hi i currently use usn diet whey meal replacement im eating 6 meals a day including shakes i want to continue to loose weight and build lean muscle is this product suitable for me?

Hi Donna If you feel you need more calories and carbs than are in the Ultralean Diet Whey to acheive your goals, then this could work but it doesn't have the fat-loss support ingredients that Ultralean Diet Whey has, so you may have to use a fat burner along with it. Regardless of which one you choose, for maximum lean muscle gains, you should add 2 grams of creatine monohydrate to two of your daily shakes.

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