Supplements | Total Shape

Instant Knockout Fat Burner Review
Read This Before You Buy

Isaac Robertson
Written by Isaac Robertson

As a fitness instructor, I work with a lot of high-performance athletes on a daily basis. It’s usually a mix of bodybuilders and just average people who need some help with weight loss, health, and fitness goals.

But I’ve also started working with MMA fighters, and one of my clients recently introduced me to Instant Knockout. While I’m a fan of fat burners, I’m also very cautious of all the dodgy weight loss pills out there.

But because of the results I have witnessed, I decided to do some more research and look into the ingredients with my dietitian to put together this detailed Instant Knockout review.

What Makes Instant Knockout Unique?

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If you’ve followed any health and fitness pages on Facebook or you just happen to read posts about body and muscle building, then you’ll quickly notice a load of suspicious fat burners filling your news feed and search results.

Fat loss is a huge business, and unfortunately, there are too many black sheep in this industry,

However, my usual suspicions about Instant Knockout were quickly reduced when I saw that there was a lot of backing from MMA fighters and coaches like Diego Sanchez and Greg Jackson.

This is one sport where they take supplements more serious than any other. 

The company behind Instant Knockout is Roar Ambition, and their goal for this product was to identify natural ingredients with a scientifically proven ability to help athletes get rid of fat and build more muscle. 

But it would have to work for professional athletes at the top of their game, as well as average people who just want to bulk up a bit or achieve some weight loss goals. 

We’ll get to the details of the nutritional label below, but I can say here that a lot of thought has gone into creating this product. Every one of the ingredients has scientific studies backing up their benefits.

While that may seem like a simple thing to do, the devil is always in the details, so I spent some time going through online reviews to see what kind of effects people were reporting.

What Are The Benefits?

men and women showing their abs

1. Fat Loss

This might be an obvious benefit of fat burners, but it really can be hit and miss with these types of supplements. However, Instant Knockout has combined a few ingredients that not only help with burning away some fat but also helps to reduce the process that stores the flabby stuff in the first place.

2. Increased Energy

When your body burns more fat, then more energy is released to fuel different parts of your body. But what I found in many different reviews is that people also noticed a good increase in mental energy and focus. 

This helps with workouts by staying motivated, but also at work and college when you need your brain to work on complex problems.

3. Appetite Suppression

One thing I often struggle with is extending my fasting periods by skipping breakfast during a cutting phase. The longer you go without food in your stomach, the more hunger hormones get released. 

But countless online reviews confirm my own experience that it works pretty well to control appetite and cravings.

4. Increased Testosterone

No, this is not some sort of dodgy steroid or banned performance enhancer. But my client had his testosterone levels tested before and after taking this product for a month. The nutrition responsible for increasing his average T-levels is zinc, which is something that many men can be deficient in.


  • Strong dosage of caffeine for mental performance and thermogenic effects

  • 10 mg of zinc boosts testosterone production for more muscle growth
  • Nice dose of glucomannan to help suppress appetite
  • check
    Includes cayenne pepper which helps with burning off more calories


  • You’ll need a reminder to take 4 pills daily

OK, with all this good stuff you can expect, what about some negatives?

Are There Any Side Effects?

Fat burners have had quite a bad reputation, and many of them can cause an upset stomach, which isn’t ideal to stay motivated on a weight loss program. 

The good news is that because Instant Knockout is made of the most natural ingredients my dietitian has encountered, side effects really are limited. 

The one area where you may want to be careful is the dose of caffeine, especially for women. With a full dosage containing 300 mg of caffeine, or the same as 2 large coffees, you can experience jitters and sleepless nights if taken too late in the day.

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If you’re planning out your daily intake, then you may want to skip a few trips to Starbucks. 

List Of Ingredients And Their Effects

Now that you have a good picture of the benefits and side effects, let’s take a closer look at how effective the ingredients are at stimulating your metabolism and brain, and stalling your appetite. 

1 - Caffeine Anhydrous

According to my dietitian, caffeine is one of the most closely studied thermogenic ingredients. This is probably why Roar Ambition decided to make it a major feature on their ingredients list. 

While some athletes have trouble with this stimulant, you should note that there is very good scientific evidence [1] backing up the claim that it encourages your metabolism to burn fat.

Caffeine Anhydrous

2 - Green Tea Extract

I used to force myself to drink some green tea every day. It’s just not a taste I enjoy, but I totally understand the antioxidant benefits it provides. But, when I found that you can get supplements that contain green tea in extract form, I jumped on the opportunity.

It only contains a small amount of caffeine, but I found a very interesting study that highlighted a direct link to fat oxidation [2]. Again, thumbs up to the designers for doing their homework.

Green Tea leaves and powder

3 - Cayenne Pepper Seeds

Cayenne pepper is a well known thermogenic, but what I found more interesting was the company’s claim that it “boosts insulin sensitivity helping improve the way you store carbs.”

Not surprisingly, at this stage of my research, I was able to find supporting studies of this [3]. Now, before you think that this means you’re in for some mouth burning experience, it only takes a small amount, and in pill form, the cayenne pepper goes straight to your stomach.

Cayenne Pepper Seeds

4 - Zinc

This metal influences a lot of processes in your body from immune health to stabilizing effects on your metabolism. This is why it’s so popular in supplements.

But of most interest for anyone trying to build more defined muscle tissue is that zinc helps to increase testosterone levels [4]. 

I saw quite a few review comments where athletes actually had some hormone level tests done before and after taking Instant Knockout and similar products with zinc. In all cases, there was a positive impact on T-count. 


5 - Green Coffee Bean

Many people think that green coffee extract is just going to be useful for delivering caffeine, but that’s actually something that it doesn’t deliver much of.

The benefit of this ingredient comes from the fact that a lot of nutrition is lost during the coffee roasting process.

I found one very interesting study that showed that green coffee helps to burn fat and improve heart health [5].

Green Coffee Bean

6 - Glucomannan

Glucomannan extract was new to me, and it’s sourced from the konjac plant. Unlike most of the other ingredients, this is not included based on an ability to burn fat in an effective way. 

Instead, glucomannan helps to deal with your appetite by delivering a good amount of dietary fiber. 

This is something many other supplements miss, in that reduced food intake results in your body sending some craving signals that you need to deal with.


7 - Chromium

This is not a mineral I was overly familiar with, and I hadn’t seen it before in supplements.

But my dietitian pointed out that increasing numbers of studies are being conducted to fully identify it’s effects on body weight [6].

It is also linked to controlling appetite, and many of the reviews I read highlighted a lack of hunger as a great positive of Instant Knockout.

Broccoli in plate

8 - Piperine

This is another one of the very versatile ingredients that have a lot of nutritional value. It’s included in many products, and my dietitian goes as far as saying it is required to make absorption rates higher for both macro and micronutrients. 

Piperine (from black pepper) can enhance the absorption or bioavailability of certain compounds, such as curcumin from turmeric.

9 - Vitamin B6

We all know how important vitamins are, and your daily nutrition intake has to cover a very wide range of them. B6 has been added due to a claimed link to the way cells repair and reproduce, which is an important factor in muscle building.

One study has proven a link, but it’s still a little bit inconclusive [7]. Just check if your multivitamin also contains B6, as you may want to avoid taking too much.

Vitamin B6

10 - Vitamin B12

The second one of the included vitamins is B12, and Instant Knockout contains more than you need every day.

Most people will link this vitamin to influencing your red blood cell count, but B12 also helps with fat metabolism [8].

Timing Your Intake

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Every time I recommend supplements like fat burners, one of the first questions is always “what time of day should you take them?”

With a single dose product, timing becomes very important, but Instant Knockout is designed to provide maximum nutrition value throughout the day by splitting your intake into 4 pills.

This spreads out the fat-burning effects and delivers a more constant stream of extra energy. One thing I noted in a few reviews was that athletes suggested setting a reminder on your phone or get into the habit of taking a capsule every time you eat a meal.

Can I Stack With Other Supplements?

If you ever check the supplements shelf of professional athletes like bodybuilders or MMA fighters, then you’ll see a lot more than fat burners and protein. See, when it comes to maximizing muscle growth and definition, there are many ways you can approach it.

Pre-workout supplements help with energy and endurance, BCAA products help with recovery, and then there are all sorts of proteins and mass gainers.

Over the course of a month and training period, there can easily be 4 or 5 different products. 

While stacking 1 or 2 products can be simple enough to achieve, if you want to get even more out of your workouts, then I suggest talking to a nutritionist to avoid health issues from having too many overlapping supplements.

Is it Suitable For Women?

For women, weight loss is often a higher priority than muscle gain. The good news is that Instant Knockout is not specifically a muscle building product. This means that women can take full advantage of effective fat burning properties to improve their health, fitness, and energy.

One thing I would caution, though, is that the amount of caffeine is quite high when the full volume is taken each day. You may want to start with just 2 or 3 capsules a day, but that has the advantage of making the bottle last longer.

Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks.

Mayo Clinic                 

Where Is The Best Place To Purchase Instant Knockout?

I always recommend buying directly from the Instant Knockout website. It is the only place that it’s officially available, and with so many counterfeit products on the market, there are too many health risks you could expose yourself to.

This is also the only way you can take advantage of the money-back guarantee, as well as some very good bulk-order prices when you buy 3 bottles in one go. Since I ordered my first supply, I now always go for the “Ultimate Shredding Stack” to save money.


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Do you take Instant Knockout with food?

Is Instant Knockout a thermogenic?

​How do you take Instant Knockout?

​Does Instant Knockout fat burner work?

Is Instant Knockout Worth The Investment?

After testing out Instant Knockout for 3 months, analyzing the content with a nutrition expert, and reading through hundreds of reviews, I have to say that this is my personal favorite, and the one I recommend to my clients.

The fat loss effect is noticeable, and I have tried it during 2 cutting phases, where each time I reached my goals a few days early.

Not only is it one of the more effective supplements on the market, but it’s also very reasonably priced. You can purchase 4 bottles of the product for $140 with free shipping.

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And once you have tried it out for a few weeks, make sure you get in contact with us on social media or use the contact page on this site. 

About the author

Isaac Robertson

Isaac Robertson

I’m a personal fitness trainer and nutritionist living in sunny Indianapolis, IN. I’ve spent the last 8 years staying at the forefront of the health and fitness industry. In that time, I’ve helped hundreds of people shed the excess weight and get into shape, maintaining their healthy new lifestyle through proper training and eating habits. You can read more about me here​.

  • Thanks to this instant knockout review, I’m now leaner and stronger! Gotta say that this fat burner is legit!

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