Thermo Burst Hardcore

GNC Pro Performance Thermo Burst Hardcore is a supplement that claims to boost your energy levels and endurance so you can work out for longer and harder. The result is that you feel less tired and may even burn up to 12 times more calories per work out.

We take an in depth look at Thermo Burst Hardcore to find out more.

Thermo Burst Hardcore Pros

  • Some of the ingredients may be effective for health and weight loss.
  • Lots of positive customer feedback. People seem to like this supplement and feel that it helps.

Thermo Burst Hardcore Cons

  • Unknown ingredients in the ingredients profile
  • Inadequate product information regarding the serving size.
  • You are required to avoid caffeine while taking it so no more coffee, tea or soda.
  • No longer easy to buy.
Watchdog Rejected Diet Pills
Thermo Burst Hardcore

Thermo Burst Hardcore Review

Thermo Burst Hardcore Facts

  • Thermo Burst Hardcore is an own brand GNC supplement.
  • No longer on sale from GNC.
  • Each bottle contains 90 capsules.

If you are serious about working out and are committed to a gym routine, Thermo Burst Hardcore may help you lose weight and push your performance to a higher level.

The principle stimulant ingredient is caffeine, which at 400mg per serving is the recommended daily upper limit according to health experts.

The caffeine content comes from Yerba Mate, Guarana and Black Tea extract, which may have added benefits for weight loss but the fact that you are advised to avoid caffeine drinks such as coffee tea and sodas will not suit everyone.

Thermo Burst Hardcore also contains Micronized L Carnitine – an amino acid which helps convert fats into energy and in micronized form is more easily absorbed by the body.

There are a couple of unknown ingredients in the formula, which is troubling.

One of these is a “proprietary thermogenic blend” which we later found out to be Capsimax. This is a patented red pepper supplement believed to be a natural thermogenic.

More worryingly there is also something listed as a “Pre Work Out Explosion Blend” which does not come with any explanation. Could this be an added stimulant?

We hate seeing unnamed ingredients like this in any formula because of safety concerns.

The remaining herbal ingredients include a large serving of ginger extract (500mg), plus lower levels of dill weed, grape seed extract and Schisandra Chinensis Fruit extract.

Thermo Burst Hardcore also contains added vitamins, which may have a special application to weight loss and fat burning as well as health.

Thermo Burst Hardcore is made by GNC – the well known supplement manufacturer and retailer. It is part of the GNC Pro Range of supplements so is aimed at athletes, fitness fans and people who work out.

We have covered numerous GNC supplements before including GNC Meta Ignite and GNC Lean Burn.

GNC are a well known respected US company. In general, the company sell supplements and products from other companies but they also manufacture their own product range. All GNC supplements are manufactured in the USA and conform to GMP (good manufacturing practice).

Thermo Burst Hardcore is not on sale any more from the GNC website but is still available from some sellers.

How to Take Thermo Burst Hardcore

The product information advises you to take three times a day.
You are advised to avoid consuming caffeine from other sources while you are using this supplement.

Thermo Burst Hardcore Concerns:

Did GNC pull the plug on Thermo Burst Hardcore because of health concerns? It seems strange it is no longer available from the GNC website or stores.
Risk of side effects. You need to avoid caffeine and possibly alcohol too but will customers realise?
If this supplement really has been clinically tested, why is there no record of this?

What Does Thermo Burst Hardcore Claim To Do?

According to the product information, this:

Clinically proven Thermogenic Blend improves endurance and athletic performance” and helps you “burn 12 times more calories after your workout

This clinical proof is explained.

In a double blind, randomized, placebo controlled cross-over study, 25 subjects exercised on a treadmill on two occasions.

On one occasion, the subjects took the herbal blend in GNC Pro Performance® Thermo Burst™ Hardcore 60 minutes before exercise and on the second occasion, they took a placebo.

When the subjects took the herbal blend in GNC Pro Performance® Thermo Burst™ Hardcore, they burned three times more calories before, 3% more calories during and 12 times more calories for up to one hour after exercise compared to when they took the placebo.

This resulted in an average cumulative total of 278 more calories burned before, during and after exercise compared to the placebo.

This sounds good but we were unable to find any reference elsewhere to the clinical trial. The results have not been published and bearing in mind the old adage “if it’s not written down it didn’t happen” this lack of clinical evidence makes the claims look questionable.

In addition, this page and product is no longer available on the GNC website. Therefore, it is possible that the results have not been as good as this suggests or that this test has not stood up to scrutiny so has been withdrawn. We have been unable to contact GNC about this.

So What Is Thermo Burst Hardcore and What Are The Ingredients?

Thermo Burst Hardcore is a fat burner/ energy booster supplement, which is designed to be used in combination with exercise and taken three times a day. Serving size is not provided. It could be that each capsule is equal to one serving. More likely each serving is equal to three capsules. This basic information is not provided.

  • Vitamin C (120mg): Essential vitamin only obtainable by diet. The body cannot manufacture or store vitamin C but it is present in all fruit and veg so easily obtainable from a balanced diet. Vitamin C is an antioxidant, which means it helps repair cell damage and protects the body from disease.
  • Niacin (20mg): Vitamin B3 or Niacin can help reduce cholesterol and is important for cardiovascular health. When taken at high levels it can cause side effects such as skin irritation and flushing. The RDA is 35mg for adults.
  • Vitamin B6 (2mg): Important vitamin for cell health. Important for maintaining energy levels and maintaining serotonin levels in the brain. B6 is necessary for the production of neurotransmitters so is essential for supporting the nervous system.
  • Pantothenic Acid (10mg): Vitamin B5 helps the body manage carbohydrates and is important for healthy skin and hair.
  • Ginger Root Extract (500mg): This is one of the principle ingredients and is a well-known remedy for nausea and sickness. It is an anti-inflammatory too so it may help with muscular problems such as joint pain.
    Some evidence suggests that it may help weight loss but most clinical testing has been carried out on rats or has been very small scale. One test on just 10 men found that it increase thermogenesis and caused feelings of satiety but it does require further investigation.
  • Yerba mate Extract (500mg): South African plant extract which contains caffeiene. Some testing suggests it may delay gastric emptying.
  • Gurana seed extract (422mg): Berry which is similar to the coffee bean but with more caffeiene. The stimulant effects of caffeiene appear to be its only effect. Caffeine can help promote weight loss and increase the metabolism but effects are variable depending on the individual’s caffeine tolerance.
  • Proprietary thermogenic blend (238.34mg): This blend is named as Capsimax– a branded pepper supplement that may help increase the metabolism and thermogenesis and is often taken as a standalone supplement.
  • Pre Work Out Explosion Blend (100mg): No details about this blend. It could be an extra stimulant ingredient but comes without details.
  • Black Tea Leaves Extract (100mg): Another ingredient, which contains caffeine, black tea leaves contain antioxidants and can help sport health and weight loss. However not as effective as green tea.
  • Schisandra Chinensis fruit extract (100mg): Promising fruit ingredient that people are getting excited about because of its so-called benefits. Schisandra is an adaptogen meaning it improves general feelings of wellbeing and increases energy. It seems to improve mental performance but although it is also supposed to increase exercise performance it lacks any real evidence.
  • Micronized L Carnitine (25mg): L Carnitine is an amino acid, which helps convert fat into energy and may have an effect upon muscle development.
  • Dill weed extract (5mg): Medicinal herb once believed to be a powerful antidote to witchcraft and is also a good accompaniment to fish. Dill requires further clinical testing. It was once believed to reduce cholesterol but this theory has been disproven. However, it is good for the digestion. At this tiny serving, unlikely to do anything at all.
  • Grape seed extract (1mg): Grape seeds are high in antioxidants and fibre but at this low serving, we cannot see it being on any value in this supplement.

So What Does All This Mean?

It seems likely that you will notice the caffeine, which at 400mg is roughly the equivalent of 4 cups of coffee. Most people will find that this supplement perks them up which could be useful before a workout.

Ginger may increase body temperature – thermogenesis – and even if it doesn’t, there is evidence that it acts as an anti-inflammatory so might aid recovery. The other listed ingredients look pretty safe and although nothing is strictly proven, this seems to be one of the safer fat burners on the market.

However, we have some serious concerns.

Firstly, if this supplement really works and is really safe why have GNC appeared to have dropped it from their stores?

Secondly, what is the Pre Explosive Blend? Nobody seems to know the answer to this, or if they do, they are not saying.

Finally, there is zero information about the serving size. If each capsule contains 400mg of caffeine and you take it three times a day this adds up to 1200mg of caffeine.

Even caffeine junkies are going to find the equivalent of 12 cups of coffee a day too much to cope with.

Does Thermo Burst Hardcore Have Any Side Effects?

Thermo Burst Hardcore may cause side effects. These are probably most likely related to the caffeine content and may include:

  • Jitteriness
  • Anxiety
  • Sleep disturbances
  • Headaches
  • Nausea
  • Increased heart rate
  • Palpitations
  • Elevated blood pressure
  • Increase in urine output

Other side effects may include:

  • Heart burn
  • Stomach discomfort
  • Diarrhoea
  • Menstrual bleeding

We imagine that when Thermo Burst Hardcore was on sale from GNC, safety information was provided. However, none of the people selling this supplement have bothered with providing any health advice or warnings.

Not suitable for individuals under 18.
Avoid if you are pregnant, breast feeding or trying to conceive.
Check with your doctor before taking if you suffer from a medical condition, especially related to heart or blood pressure.
Ask your doctor for advice if you are taking prescription medication in case of interactions.
Avoid caffeine in other forms such as coffee, tea or sodas and do not drink alcohol while you are using the supplement.

Any Thermo Burst Hardcore Reviews From Customers?

There is a lot of positive feedback for Thermo Burst Hardcore.

Some customers have said they have been using it for years, with many using it solely for enhancing workouts and fitness and not as an all day energy booster.

This customer reported:

Love the product…..I don’t take the full 3 caps because I drink it with coffee in the morning before my run but you def. get a little kick. Mine wears off however after the gym and I DO feel a little tired (caffeine drop).

I use it just for the gym (6am workouts need SOMETHING to get you going) not for all day energy support

Some customers have mentioned the taste of the capsules:

Good product…drink with plenty of water…stings the tongue if you don’t swallow fast


Definitely increases your body temp. I sweat much more during my workouts when I take this product. It does have a very strong taste, not a bad taste, but very strong…

We expect this is the effect of the 500mg of ginger.

Some customers have mentioned side effects.

It does give me energy before workouts, but I get some nausea sometimes.


Often left a burning feeling in my stomach (yes I ate) or I was jittery. I lowered it to two pills. But if that stuff is anywhere in your system for the day or whatever and you’re a moderate drinker. It’s going to comeback up.

Do not take with caffeine. It will increase your heart rate and make you jittery.

So Does Thermo Burst Hardcore Work?

It will probably work if you are looking for a little kick to get your exercise started but there are no guarantees that feeling more energetic will really translate to weight loss and we would not recommend that you take it throughout the day.

In addition, there are some safety concerns. Some customers have mentioned jitteriness and other side effects especially if combined with added caffeine or even a moderate amount of alcohol.

There is no evidence that the supposed 12 X fat burning effect is real either. There is no record anywhere of this clinical test apart from the claims of the advertising.

The bottom line is that Thermo Burst Hardcore may give you a quick energy boost but is extremely unlikely to work in the way as described.

Where Can I Buy Thermo Burst Hardcore?

Thermo Burst Hardcore is no longer available from GNC stores or via the GNC website. It is also no longer on sale via Amazon USA so you will have to search to find it.

A 90-tablet bottle (1 month’s supply) costs between $15 to $25 depending on where you go.

Outside the USA, we have seen a “lite” version with less caffeine on sale in the UK for around £14.99 a bottle.

It is also available in India from Health Kart for around 2600 rupees ($40).

What About A Guarantee

Thermo Burst Hardcore is not covered by a guarantee.

Watchdog Verdict

Thermo Burst Hardcore has some good points. It comes with a lot of positive customer feedback and we like some of the ingredients. However, we do have concerns.

The publicised clinical test that claims you can burn 12x more calories does not appear to have been documented so is not really proven.

We are very concerned about the high levels of caffeine, which you are advised to take each day, and there is the matter of the unknown blend the Pre Workout Explosion Blend. What does this actually contain? Nobody knows for sure.

In addition, this supplement seems to have been dropped by GNC, which is odd seeing as it appeared to be popular. Do GNC have a reason for this that they are not telling us about?

In our opinion, Thermo burst Hardcore may be OK to take occasionally before a workout because it will perk you up but there are too many unanswered questions about this supplement to recommend it, even for occasional use.

It will not be easy to buy either and we imagine that the few sellers who stock it are simply using up old stock.

In our opinion, Thermo Burst Hardcore is all looking a bit bargain basement and this combined with our concerns leads us to only one decision. We reject Thermo Burst Hardcore.

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Disclaimer: Our reviews and investigations are based on extensive research from the information publicly available to us and consumers at the time of first publishing the post. Information is based on our personal opinion and whilst we endeavour to ensure information is up-to-date, manufacturers do from time to time change their products and future research may disagree with our findings. If you feel any of the information is inaccurate, please contact us and we will review the information provided.

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