Nutrition

Fat burner or money waster?
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You've probably heard of omega-3 and omega-6 fatty acids. Eating too much omega-6 containing foods can lead to cancer, cardiovascular disease and excessive inflammation. And the consumption of omega-3 fatty acids is important because it can keep these inflammations under control. But there is an exception to the omega-6 fatty acids and that is gamma-linolenic acid, or GLA for short.

What is GLA?

GLA is considered an essential fatty acid. Whenever a nutrient is labeled as "essential" it means that you have to eat it to get it. Your body can't make this nutrient on its own like it can with many other things. The two essential fatty acids you need to consume in your diet are omega-3 and omega-6 fatty acids. However, you shouldn't overdo it and eat tons of omega-6 fatty acids. That's what most Americans do and it's the cause of some problems. GLA is an omega-6 fatty acid, but a special one. If you're familiar with omega-3 fatty acids, then you know their ability to regulate inflammation. And because of this fact, you may also take fish oil capsules. Well, what makes GLA so special is the fact that GLA is an omega-6 fatty acid that does not cause inflammation. In fact, GLA reduces inflammation.

Is GLA a fat burner?

There are many claims regarding the effects of GLA, including its ability to burn fat. Some even go so far as to say that GLA is the dietary fat that burns fat. Why? Because they believe that GLA activates what is known as brown adipose tissue. You need to know that the body has two different types of adipose tissue: brown adipose tissue and white adipose tissue. Brown adipose tissue is considered to be metabolically active tissue, which means that it contributes to the body's thermoregulation and therefore also to energy consumption. Sounds pretty cool, doesn't it? But wait, before you go searching on Google for all the things that could increase brown adipose tissue activity, you should be aware that you probably won't get that far.

Hibernating mammals have more brown adipose tissue than humans because this adipose tissue is needed for thermoregulation during the long winter nap. Of course, humans also have brown adipose tissue, but in humans this is mainly a phenomenon during infancy. It serves as a protective mechanism to keep babies warm, as they do not have the necessary muscles to shiver and thus produce heat. As we get older, the amount of brown adipose tissue decreases and the amount that remains varies from person to person. So you will still have brown adipose tissue, but not as much as you used to and you may not be able to increase this amount. A study published in the Journal of Obesity showed that brown adipose tissue could be identified in adult humans who were exposed to cold for two hours by placing their legs on a block of ice. After the subjects underwent this process, activation of brown adipose tissue was observed in the supraclavicular and paraspinal regions.

However, the weak point of the study is that it only included thirteen subjects and only six of them showed activation of brown adipose tissue. Unless you lie down on a block of ice for two hours and spend a lot of money on the relevant evaluations, you won't know how much brown adipose tissue you have or how active it is in your body. And there's probably a 50% chance that you won't have much brown adipose tissue in adulthood.

But what if I am one of the 50% who have activatable brown adipose tissue?

Let's assume that you are one of the people who have some brown adipose tissue. Then you would be the type of person who could burn a ton of fat by using GLA, right? In a way, yes.

The study that most people are referring to in this context comes from Japan and was published in the Journal of Comparative Biochemistry and Physiology. This study was able to show that brown adipose tissue was activated in a group that was given GLA and that this group of subjects gained less body fat than the control group. Is this proof that GLA works? Not necessarily, because there are a few things you should know. First of all, this study was conducted with rats as study subjects. Animal studies are used as a first step to find out if there is reason to believe that a nutrient has therapeutic effects in humans. If this is the case, a study is conducted with humans as subjects. And sometimes results can be observed in rats that cannot later be observed in humans. So this is simply a transfer of data from rats to humans. But there are also some studies that show that GLA can contribute to fat loss in humans. The fact is, however, that there are a few problems with these studies. The biggest problem is the type of subjects that were used.

For example, a study published in the Journal of Nutrition showed that GLA can reduce weight gain in people who were previously very overweight. If you are a formerly obese person, then this could also apply to you. However, if you are a regular fit person who has never been obese, this may not necessarily apply to you. GLA has been shown to help prevent weight gain, but that doesn't necessarily mean that it can help an already quite slim person reduce their body fat percentage from twelve to six percent. This requires good old hard work and a smart diet.

Conclusion: As long as there are no further studies carried out on humans, it is not clear to what extent GLA can contribute to fat loss in people who exercise. There is no harm in taking GLA, as it is safe and has other health benefits, but no one can say in advance to what extent it can help you lose fat.

Better proven benefits of GLA

Let's dig a little deeper into the science. Your body's ultimate goal is to get dihomo gamma-linolenic acid (DGLA), which is a derivative of GLA. DGLA can reduce inflammation in two ways. Firstly, it is converted into PGE1, which has anti-inflammatory effects. Secondly, it can be converted to 15-HETrE via the 15-lipoxygenase pathway, which has the ability to inhibit the formation of 5-lipoxygenase, which can lead to the formation of pro-inflammatory metabolites.

If you look at the diagram above, you can see that linoleic acid can be converted to GLA and then to DGLA. At this point, DGLA can have a direct anti-inflammatory effect by producing PGE1 or an indirect effect via the production of 15-HEtrE. You might think that consuming more linoleic acid (an omega-6 fatty acid) should be enough to have more GLA and consequently more DGLA.

But what may look good on paper doesn't always work as intended in real life. When it comes to the conversion of certain nutrients, enzymes are needed. In this case, the body needs an enzyme called delta-6-desaturase (D6D). This enzyme converts linoleic acid into GLA. This has to happen so that DGLA can ultimately be produced. The problem, however, is that D6D levels decrease with age and due to stress, radiation, sugar, caffeine, trans fats, diabetes and alcohol.

So we can almost certainly assume that many of us suffer from declining D6D levels. Even if you don't eat sugar or drink alcohol, you're likely to suffer from some stress, be exposed to some amount of radiation and of course get older, which decreases your body's ability to produce GLA. This is why with GLA supplementation you can bypass the D6D pathway, which limits the rate of GLA production, to increase your levels of GLA, which can be quickly converted to DGLA.

Who should consider supplementing with GLA?

I would consider GLA if I were an older strength athlete. This is another pathway to help keep inflammation at bay and improve recovery. For the strength athletes out there who struggle with using non-steroidal anti-inflammatory drugs to treat joint pain, GLA could be a useful approach. A study published in the Journal of Rheumatic Disease showed that GLA has benefits for subjects with rheumatoid arthritis. This study included 3 groups:

  • A control group
  • A group that took evening primrose oil
  • A group that took evening primrose oil and fish oil

GLA is found in vegetable seed oils such as evening primrose oil and borage oil. After twelve months of supplementation, 11 out of 15 subjects from the evening primrose oil group and 12 out of 15 subjects from the evening primrose oil and fish oil group were able to discontinue their pain medication. Only 5 out of 15 subjects from the control group were able to reduce their use of pain medication. Those are pretty darn good results for a vegetable oil! You may not suffer from arthritis, but the cause of common problems like rheumatoid arthritis, osteoarthritis and joint pain is inflammation. GLA is one way to create an anti-inflammatory effect.

Depending on which oil you choose, GLA levels will vary. The dosage used in most studies was around 540 mg of GLA per day. So you don't need huge amounts of GLA to benefit from its positive effects. The bottom line is that GLA is not super promising in terms of fat loss. But if you have a bit of stress, drink a lot of coffee or are getting older, then GLA is a good choice when it comes to keeping inflammation under control.

By Robert Yang
Source: https://www.t-nation.com/supplements/fat-burner-or-money-waster

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Supplements vs. whole foods
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Ask your doctor. Ask your nutritionist. Ask the health authorities. They will all tell you the same thing:

You probably don't need supplements. Just eat whole foods. These are much better. And supplements - well, they're questionable in a way anyway. Didn't you hear about that wrestler who died from steroid creatine? Just drink your fat-free corn syrup and stop asking for supplements, okay? Now go on. Now, with all due respect to my doctor (who spent an entire hour learning about supplements in college 25 years ago) and to my nutritionist (who is incongruously kind of bacon-y) and to my government (which still recommends that the overweight portion of the population eat lots of bread) we're not just going to move on, we're going to ask questions.
And who better to ask these questions than Dr. Lonnie Lowery, who is a renowned nutritionist, bodybuilder and academic who has been involved in supplement research since 1989.

I called him a few days ago and asked him a seemingly simple question: "Are whole foods always superior to supplements?"

Here's what he had to say:

Preface

"Let me state the obvious first," he began. "Whole foods should make up the bulk of your long-term diet. Athletes need to learn how to incorporate them into their lifestyle. We humans have evolved with unprocessed plant and animal foods for hundreds of thousands of years, and our biochemistry is designed to consume these foods."

"But terms like 'natural' have been misused to the point where health authorities have issued warnings about over-interpretation of these terms. Let's defend supplements for simplicity's sake, because so few authorities do." And so we began.

Protein shakes vs. regular meals

You may not believe it, but there are some crazy people out there doing protein shake diets. No, really. And while you'd expect learned academics to scoff at this, Dr. Lowery said times are changing. "I've seen three studies that support the idea that meal replacement shakes are effective for fat loss and may be better than traditional diets," he noted. One idea is to start a healthy diet with a protein shake diet, get rapid results and then move on to a healthy eating plan with solid foods. "Protein keeps your metabolic rate high and helps protect muscle tissue," Lowery said. "The medical community has been using diets consisting primarily of protein shakes in clinical settings for years: protein-sparing modified fasting (PSMF). I think it's kind of odd that certain health organizations are trying to demonize protein drinks and at the same time use them to treat morbidly obese people. Lowery also noted that much of the effectiveness of protein shakes has to do with the ease of adherence to these diet plans. Drink several protein shakes a day and you'll be less hungry than the typical dieter. Shakes are also easy to take with you, they taste good if they're from the right manufacturer, and there's less room for error while dieting (your meals are convenient, you can take them anywhere, you don't have to count calories, you don't have to read labels, and you don't have to make choices). Lowery also emphasized that protein shakes are often superior to whole foods when it comes to achieving a calorie surplus. "That's what it takes to build muscle - a surplus of calories, about 2800 kcal, to build a pound of muscle," Lowery said. "With shakes, this is very easy because you can just add what you want. I've even made chocolate shakes with graham crackers!" Studies often confirm what we bodybuilders have known for years: drinking extra calories is easier than chewing them. The problem with solid food meals is that after one or two of these meals, the strength athlete looking to build muscle often compensates for the extra food intake later in the day by eating less. They are simply full. Liquids, on the other hand, pass through the stomach much more quickly.

"The summary at this point is that protein shakes work for both dieting phases and mass-building phases, and they often work better than solid foods from a diet plan adherence perspective," Lowery said. "I'm not saying you should live on liquids forever, but these shakes can be used to start a fat loss plan or to increase caloric intake on a mass-building plan." For a long-term bodybuilding plan, refer to the advice of Lowery's old mentor, Dr. Peter Lemon, who recommended that his subjects consume no more than 50% of their calories in the form of liquid supplements.

Bodybuilding supplements are bad! Supplements for old people are good!

Speaking of meal replacement shakes, have you ever noticed that many medical professionals demonize protein shakes and then in the next breath recommend drinks like Ensure or Carnation Instant Breakfast?

Ready-made shakes like these promise a "complete and balanced diet" and the Ensure website advises "It's your health, take care of it!" Let's look at the list of ingredients... The primary ingredients come from corn syrup, sugar, maltodextrin and soy protein.

What the heck is going on here? Dr. Lowery enlightens us:

"When doctors in hospitals gave their patients the usual 'clinical' supplement drinks, they were pumping sick people full of sugar and/or vegetable oil. Why? I asked them. They said it's because these drinks taste good and sick people don't eat enough anyway. My answer was 'Then why don't we make good food that tastes better?" Vegetable oil (such as safflower oil, palm oil or soybean oil) mixed with sugar is one of the most fattening and pro-inflammatory mixtures you can consume, according to Dr. Lowery. I would bet that these people would be better off with products from the sports supplement industry, which are demonized by the same clinical doctors. "They would probably love sports nutrition drinks if you changed the label and didn't tell them it was a bodybuilding supplement," Lowery added.

The problem with perishability

Protein foods spoil quickly, which is not the case with protein powder. Simply put, bacteria multiply much slower in dry foods than in wet foods.

"The best thing you can do is pour protein powder dry and without water into a shaker bottle and then take it with you. Then you can add water later," Lowery said. Dr. Lowery works a lot with college athletes, most of whom skip meals. "It's terrible," he said, "I'm constantly faced with the challenge of getting them to eat protein foods when they're out all day. Protein foods go bad quickly unless you're eating tuna straight out of the can between courses. In this situation, protein powders are very suitable. Some people take their protein powder with them in dry form in a shaker bottle and mix it with water when they need it. This way they don't waste all their efforts in the gym by skipping meals."

Unfortunately, Dr. L and NCAA programs generally can't directly administer drinks that contain more than 30% protein. Yes, you heard that right. Despite all the controversy, this rule still stands. Sadly, it's a rule that can banish a commonly needed tool from athletes' nutritional arsenal. Even supplements that contain fat can beat whole foods when it comes to perishability. Long-chain unsaturated fats like fish oil or flaxseed oil go rancid quickly at room temperature, but this doesn't happen as quickly when these oils are put into capsules because oxygen can't get to the good stuff. "A lot of people in the health industry seem to think that once you put a nutrient in capsules it becomes something bad. But you don't change a nutrient just because you put it in capsules," Dr. Lowery said. Perishability may not seem like a big issue, but at a time when most people are away from home, have shorter breakfast breaks, longer commutes to work and are generally busier than ever, it's crucial to have 'portable' foods that won't go bad, which is especially true if you're a bodybuilder or athlete who's on the go.

Nutrient content: pill vs. fork

"You can pack enormous amounts of EPA/DHA into fish oil gel capsules - more than you'll probably ever get from eating fish," Dr. Lowery said. And if you were to eat that much fish, you should remember that we live in a polluted world. Whether it's farmed fish or wild-caught fish, it's often contaminated with heavy metals or organic pesticides. I would rather use a highly concentrated, pure fish oil supplement that I trust." Lowery noted that he has nothing against eating salmon, cod and other fish, but a bodybuilder simply can't get enough of the good stuff if he only eats fish and doesn't take a fish oil supplement. And even if he could, there's still the contamination problem mentioned above to worry about if the daily fish intake is high.

"And it's not just fish oil," Lowery said, "but also things like CLA. You can easily take a couple grams of CLA a day in supplement form, but you'd have to consume gigantic, unrealistic amounts of dairy, beef and turkey to consume those amounts."

Creatine falls into the same category. It would take about 10 pounds of raw steak to get the amount of creatine you need for a creatine loading phase. Certainly creatine supplements are superior to whole foods in this regard (and only cost about 10 cents per serving). Vitamin D? The same applies here. You simply can't drink enough vitamin D-fortified milk to get your vitamin D blood levels into a healthy range. Most of us supplement. "This is especially true for those of us who live in areas where sunshine is simply not an option right now," added the pale white Lowery. Now, if there are any doctors, nutritionists or health department workers out there telling us we should be drinking 45 liters of milk a day instead of taking a four-cent vitamin D pill, I'm at a loss too.

But supplements are processed! And processed is always bad, right?

Not necessarily. Fish oil supplements, for example, are processed to remove all the bad stuff like mercury. Dairy protein supplements are processed to remove all the lactose and other stuff we don't want, while keeping all the good stuff we do want.

"The term 'processed' as it applies to supplements does not mean that important ingredients are removed, as is often the case when we talk about processed foods (where insane amounts of sodium are added, for example). The intent of processing in this case is to make something better," Lowery said. Still, Dr. Lowery often hears criticism regarding nutritional supplements. "The only time this makes sense is when we're talking about an incomplete protein or amino acid supplement, but no halfway sane protein consumer would subsist on just an incomplete protein source or amino acid tablets." "Don't get me wrong," Lowery added, "some protein supplements are full of junk. For example, I've seen a protein powder that contained 10,000 mg of peptide-bound amino acids. But that's only 10 grams of protein. That's the equivalent of a cup of milk! You don't measure protein in milligrams."

And protein bars? Don't even get me started. "Athletes need to be aware that the 25 grams of protein on the label could be mostly worthless. Some companies add biologically worthless collagen and gelatin to their bars to improve the stats. Please people, take a closer look. Read the ingredients list of your protein bar and make sure it doesn't contain any of these worthless useless protein sources high up in the ingredients list," advises Lowery. In summary, legitimately processed supplements are not a problem. They're processed to remove the stuff we don't want. And processed carbohydrate foods? Not so good. With these foods, food manufacturers remove stuff we want, like fiber.

Nutrient timing

Supplements can have other advantages over whole foods: precise nutrient timing. While foods deliver the things we want slowly, supplements can deliver those ingredients in the precise amounts you want, when you want them.

Let's take one of Lowery's favorites: Caffeine. If you want a quick boost of exactly 200mg of caffeine, you can simply pop a caffeine tablet. Drinking coffee is fine, but "imprecise". You can't drink it on the go, it doesn't work as quickly and the exact caffeine content can vary. In addition to this, unless it's iced coffee, coffee doesn't sound particularly appealing on a hot summer day before squats. "People tend to drink coffee like they smoke. It's sipped throughout the day," Lowery says. "I'm not sure that low levels of caffeine throughout the day are going to do much. They're not going to do much, at least in terms of performance. To boost performance, you need a bigger boost of caffeine at a well-defined time. Most studies recommend six milligrams per kilogram of body weight (probably less if you're looking to stimulate fat burning). And remember that caffeine is not exactly the same as coffee." Even though he loves his coffee, Lowery concludes that it's probably healthier and more effective to dose caffeine as a supplement than to drink cup after cup of coffee throughout the day. In other words, you are using your substance of choice tactically.

Fiber without carbohydrates

What's the first thing you notice when you start a strict low-carb diet? You will realize that you would sell your soul for a Dorito. What's the second thing you'll notice? Yes, sometimes it is difficult to reduce carbohydrates and still get sufficient amounts of fiber. Supplements can be beneficial here too. "There are plenty of foods that can give you plenty of fiber while keeping your carbs low. Think high-fiber vegetables like broccoli and cauliflower," Lowery says. "I'd rather see people choose whole foods if they can stick to that path. Vegetables are definitely better than fiber supplements. But let's be realistic, some people just don't like vegetables or don't have the time or desire to prepare vegetables." This brings us back to the issue of adhering to a specific diet. Yes, it is possible to consume adequate amounts of fiber as part of a low-carb diet, but is it easy for a dieter who works all day at the office or has classes? In these cases, consuming a fiber supplement or adding fiber to something you're already drinking anyway may probably be more realistic than steaming a pound of broccoli at your desk on your coffee break. And remember that there are some low-carb diets that don't allow vegetables to begin with. In these cases, fiber supplements can come in handy. Whole foods are definitely better when it comes to fiber intake. The intake of all the cancer-fighting phytochemicals you get in conjunction with your fiber is simply unbeatable. But fiber supplements are a quick and convenient part of the overall picture if you're having trouble maintaining a perfect diet.

Phytochemicals: This is where whole foods win

Up to this point, we've highlighted often overlooked benefits of supplements. But there are cases where and nature is simply too far ahead in terms of time and experience and where whole foods win hands down. "Fruits and vegetables contain healthy phytochemicals that work together metabolically in unknown combinations," says Lowery. "Supplements don't always work in the same way that whole foods do in this addiction." Here's an example: the famous study on beta-carotene and smoking. Basically, they found that smokers who eat a lot of beta-carotene-rich fruits and vegetables don't get lung cancer as quickly. The smart guys in lab coats conducted a clinical trial in which they gave smokers only beta-carotene in supplement form. To the scientists' surprise, lung cancer rates increased in the subjects who consumed beta-carotene only in supplement form.

"This is a classic example of why we should trust Mother Nature and a whole foods approach," Lowery said.

Supplements vs. food: the bottom line

Despite the warnings against pills and powders by doctors and washed-up nutritionists, supplements can do a lot of things that whole foods can't. Good examples include creatine, fish oil, CLA, vitamin D and other things like resveratrol, which you simply can't get enough of in the form of whole foods to have a medicinal or performance-enhancing effect. Even protein powders are now considered by the scientific community as supplements with strategic benefits over whole foods.

Dietary compliance also plays a major role here. Even though eating tons of organic green vegetables and exotic berries every day has a lot of benefits, in reality we are more likely to follow a diet with a superfood supplement. This simply saves time and money. But in context, Mother Nature is a wise bride and she knows more about the magical interplay of phytochemicals and human physiology than we do. Is Dr. Lowery saying that you should replace whole foods with supplements? Of course not. But he does say that supplements can sometimes have clear benefits over whole foods. The science is catching up. This means that nutritionists and even the government will catch up in 15 to 20 years. Until then, eat your whole foods and take your pills and powders.

By Chris Shugart
Source: https://www.t-nation.com/supplements/supplements-vs-whole-foods

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Whey protein powder
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Whey protein powder:

A complete A-Z guide to all types of whey protein supplements

Whey protein is considered a basic supplement used by athletes, bodybuilders and fitness enthusiasts to support muscle recovery, lean muscle mass gain and overall health.

This guide will teach you the following:

  • What whey protein is and where it comes from.
  • Who can benefit from using whey protein supplements.
  • How to choose the right whey protein supplement.
  • How much whey protein you should use and what the best times are.

What is whey protein?

Whey protein is a term used to describe a group of milk proteins that are isolated from whey, which is a by-product of the coagulation of milk during the cheese-making process. Most people think that whey protein is simply a mixture of the typical amino acids we know, but in reality whey protein contains many more molecules.

The mixture of proteins usually contains about 65% beta-lactoglobulin, 25% alpha-lactalbumin, 8% bovine serum albumin and small amounts of immunoglobulins, lactose and fat.

How is whey protein produced?

Whey protein can be made directly from milk or even cheese, but almost all known brands of whey protein are made directly from milk.

First, the whey protein is separated from the milk using a sieving process. The result is a liquid whey product. Then the first step is pasteurization using an ultra-high, short heating process.

Basically, the product is heated to the required minimum temperature of 161 °F for 15 seconds. Milk is pasteurized to kill any harmful bacteria that may be present in the milk.

The next step is to isolate the protein from the liquid whey. This can be achieved by ion exchange or mechanical filtration.

The ion exchange process often requires the use of acids (e.g. hydrochloric acid) or bases (e.g. sodium hydroxide), which can lead to denaturation of the protein.

While the chemical-based process of ion exchange is cheaper and often allows more amino acids to be isolated, the disadvantage of this process is that some of the other important compounds contained in whey protein, such as lactoferrin and many of the immunoglobulins, are lost.

The mechanical filtration process, often known as cross-flow filtration, is a physical process that often results in a better product. However, this process can be more expensive and laborious.

The type and sizes of filters used and the number of successive filtration steps are key to what type of whey protein is produced. The finer the filter and the more frequently the product is filtered, the purer the end product will be. With each filtration step, the amount of lactose, fat, ash and other small impurities in the final product decreases.

The type of filter and the number of filtration steps are the primary difference in the production of different types of whey protein (primarily isolates and concentrates)

Types of whey protein

There are three main types of commercially available whey proteins: Whey protein isolate, whey protein concentrate and whey protein hydrolysate. Let's look at these in detail:

Whey protein isolate

Whey protein isolate is considered to be the purest form of whey protein available. It contains between 90 and 95% whey protein, very little fat (0.5 to 1%) and very little lactose (0.5 to 1%). This makes whey protein isolate a good source of protein for people who suffer from lactose intolerance or other lactose digestion issues.

One thing that should be mentioned is that whey protein isolate often lacks a lot of the other beneficial compounds of whey protein including immunoglobulins and other small molecules that have beneficial properties for health. So if you opt for whey protein isolate, you may be missing out on some of the magic.

Whey protein concentrate

Whey protein concentrate has a lower protein content, typically ranging from 25 to 98%, with most commercially available concentrates containing between 70 and 80% protein. Whey protein concentrate often contains between 4 and 8% lactose, fat and other minerals.

This type of whey protein is also commonly found in protein bars and other food products.

Whey protein hydrolysates

Whey protein hydrolysates - also known as hydrolyzed whey protein - consist of whey protein that has been enzymatically treated to break down long protein chains into shorter ones. This process makes the whey protein easier to absorb by the body and often reduces the potential for allergic reactions and digestive problems. As such, it is often used in infant products, sports products and medical nutrition products.

A direct comparison of the primary types of whey protein

Type of whey protein

Protein concentration

Other compounds

Allergens

Whey protein isolate

90 - 95% whey protein

Only traces of fat, lactose or other minerals

Low in case of lactose intolerance, high in case of milk protein allergy

Whey protein concentrate

25-89% whey protein. Typical concentrations found in commercial products are 80%

Contains some fat, lactose and other minerals. Typically, the amount of these ingredients decreases as the protein concentration increases.

High for lactose intolerance, high for milk protein allergy

Whey protein hydrolyzate

80 - 90% whey protein, whereby the concentration varies greatly from product to product

Highly variable from product to product

High for lactose intolerance, low for milk protein allergy

The benefits of whey protein

Whey protein supplementation is very popular among athletes as it has been reported to increase athletic performance. Whey protein is a popular protein supplement designed to provide increased muscle strength and improved body composition due to its high content of essential amino acids and branched-chain amino acids, resulting in a higher biological value (1-4).

In addition, whey protein supplementation has been shown to reduce oxidative stress by increasing endogenous glutathione production and improve compromised digestive health associated with intense exercise (5-8).

While most of the topics discussed in this article are specific to whey protein supplementation, I would like to remind everyone that whole food sources of whey protein may be superior to whey protein supplementation in terms of nutritional synergy.

Increased strength and lean body mass

Most sporting events rely on muscle force production, and a greater ability to produce force is associated with increased performance. Since force equals mass times acceleration (F = M * A), increasing muscle mass is the most common way athletes aim to increase their force production.

Skeletal muscle hypertrophy requires proper resistance training and nutritional status in which muscle protein synthesis exceeds muscle protein breakdown.

One of the main concepts in the literature dealing with skeletal muscle hypertrophy is the idea of net protein balance. Net protein balance is defined as muscle protein synthesis minus muscle protein breakdown. Thus, skeletal muscle hypertrophy will occur if muscle protein synthesis is higher than muscle protein breakdown (9).

One of the critical factors influencing muscle protein synthesis and muscle protein breakdown is the availability of amino acids (10, 11). Whey protein supplementation is a source of amino acids with high biological value and is said to increase muscle mass and strength.

There is a large body of scientific research that has investigated the effectiveness of whey protein supplementation in increasing strength and muscle mass. The results of these studies are not completely consistent, but a large body of evidence suggests that whey protein supplementation increases both strength and muscle mass (12-15).

In addition, scientists have recently shown that whey protein ingredients upregulate cell signaling pathways - specifically mTOR - that are responsible for muscle protein synthesis and muscle hypertrophy (16).

Whey protein and glutathione

Oxidative stress represents an imbalance between the antioxidant defense system and the production of reactive oxygen species (17). Oxygen consumption during heavy exercise can increase up to 100 times normal levels at rest, increasing free radical production, resulting in oxidative stress.

Although the data is inconclusive, existing studies show increased free radical production and increased cellular damage after heavy resistance training (18).

Athletes are at higher risk of oxidative stress than their physically inactive counterparts due to the increased pro-oxidant processes they expose themselves to (19). The increased levels of oxidative oxygen species produced during heavy exercise must be reduced by the body's own antioxidant system to maintain an oxidative balance.

Glutathione, the most abundant and important antioxidant in the body, is a tripeptide synthesized from the amino acids L-cysteine, L-glutamic acid and glycine (20). Glutathione plays a crucial role in antioxidant defense, nutrient metabolism and the regulation of pathways essential for the body's homeostasis (21).

In addition, glutathione serves as a regulatory compound in the activation of lymphocytes of the immune system (22).

It is evident that glutathione is a crucial compound for maintaining health and a deficiency of glutathione has been linked to numerous pathological conditions including cancer, neurodegenerative disorders, cystic fibrosis, HIV and aging (23). Glutathione is of particular interest to athletes as glutathione concentrations vary greatly as a result of dietary restrictions, training and oxidative stress.

The immense physical demands of sport expose the athlete's body to a high level of physiological stress. Glutathione plays a crucial role in maintaining a normal redox status during exercise (24, 25). Furthermore, it has been shown that exhaustive exercise reduces glutathione status (24, 25, 26).

This points to the need for increased glutathione levels in athletes. Scientists have shown that the amino acid cysteine is the rate-limiting factor in glutathione synthesis (27, 28). For this reason, the inclusion of a cysteine-rich protein source in the diet may prove effective in increasing the rate of glutathione resynthesis through the availability of sufficient amounts of cysteine in the amino acid pool.

However, supplementation with free cysteine is not recommended as it is spontaneously oxidized and such supplementation has been shown to be toxic (29). Dietary sources of cysteine in the form of cystine (two cysteine molecules linked by a disulfide bond) are more stable than free cysteine and are digested correctly. Whey protein supplements, including whey protein isolate and whey protein concentrate, are rich in cysteine and deliver cysteine to the body's cells via normal metabolic pathways (30, 31).

By providing a sufficient amount of cysteine, whey protein supplementation allows cells to synthesize glutathione and replenish glutathione reserves without undesirable side effects (31). (Thus, whey protein supplementation may serve to increase endogenous production of glutathione and alleviate oxidative stress in athletes).

The use of whey protein supplementation to alleviate exercise-induced decreases in blood glutathione levels has been extensively studied. Research has shown that whey protein supplementation is helpful in maintaining normal physiologic glutathione levels in athletic and non-athletic populations in response to exercise (32-24).

In addition, scientific research has shown that whey protein improves an athlete's ability to cope with acute oxidative stress and whey protein may therefore serve as a safe and effective alternative source of antioxidants for the prevention of sports injuries and illnesses caused by excessive levels of reactive oxygen species (35).

The research regarding whey protein supplements and glutathione status supports the use of whey protein to improve health status in athletes by enhancing the endogenous antioxidant system.

Whey protein and immune function

Strenuous exercise and heavy training programs have been associated with suppression of immune cell function (36-40). In addition, an inadequate or inappropriate diet can exacerbate the negative impact of heavy exercise on immune function. Suppression of immune function exposes the individual to an increased risk of infection.

Athletes increase both the volume and intensity of their training during certain phases of the season, which can result in a state of overreaching or overtraining. Recent research suggests that immune function is indeed sensitive to increases in training volume and intensity.

Although these studies have not shown that athletes are clinically immunocompromised during these periods of suppressed immune function, this condition may still be sufficient to increase the risk of widespread infections.

Because the components of the immune system are highly dependent on amino acids, endogenous and dietary amino acids can influence the status of the immune system.

Scientific research shows that whey protein is unique compared to other protein sources in its ability to promote strong immune function via numerous beneficial compounds including glutamine, α-lactalbumin and β-lactoglobulin and small protein fractions such as serum proteins, lactoferrin and a range of immunoglobulins (41 - 43).

Whey protein and the health of the digestive tract

Intense exercise leads to reduced blood flow to the internal organs, reduced blood flow to the digestive tract and increased temperatures in the gut (4). Reduced blood flow to the intestine and high temperatures in the intestine during exercise can lead to intestinal barrier dysfunction due to increased permeability of the impermeable junctions (5, 8).

This increased permeability of the intestinal wall leads to an invasion of gram-negative intestinal bacteria and/or their toxic components (endotoxins) into the blood circulation (45 - 47). Endotoxins are highly toxic lipopolysaccharides of the outer cell wall of gram-negative bacteria. Lipopolysaccharides are a primary trigger for an immune response in vivo via induction of the cytokine network (45). (Jeukendrup, et al., 2000).

This process, known as enditomexia, may result in increased susceptibility to infection and autoimmune disease due to absorption of pathogens/toxins into the bloodstream and tissues (48).

The research area of gut wall permeability is still relatively new and prospective long-term studies have yet to identify the potential health risks of chronic low-grade gut wall permeability.

However, recent studies have established a link between intestinal wall permeability and a number of autoimmune diseases including Chron's disease, Hashimoto's disease, lupus erythematosis, psoriasis and rheumatoid arthritis (49-53). In addition, gut wall permeability has been linked to mental illnesses including schizophrenia and depression (54, 55).

As previously mentioned, impermeable compounds are a major component of intestinal barrier function, acting as a physical and functional barrier against paracellular penetration by macromolecules from the lumen (56, 57). Therefore, regulating the permeability of impermeable compounds is critical for maintaining integrity and reducing the entry of endotoxins into the body.

The amino acid glutamine is critical for maintaining these impermeable junctions (56). Glutamine is the most abundant amino acid in the blood and is considered a conditionally essential amino acid (56). Under normal circumstances, glutamine is produced by the body in sufficient quantities to maintain normal physiological functions.

In stressful situations such as physical training, endogenous glutamine production may be insufficient, so the body must rely on exogenous (externally supplied) sources of glutamine to meet its needs.

Glutamine supplementation has been shown to normalize the permeability of the intestinal wall, which has been compromised by a number of physiological stressors, by restoring the integrity of impermeable junctions (58-60). In addition, glutamine supplementation has been shown to be effective in reducing exercise-induced increased intestinal wall permeability (61).

Whey protein is a rich source of glutamine and researchers have shown that whey protein supplementation is able to reduce increased intestinal wall permeability (62, 63). For this reason, whey protein may be useful in reducing exercise-induced increased intestinal wall permeability and the risk of endotoxemia and autoimmune disorders.

Summary

Whey protein is an excellent source of a wide range of amino acids and additional nutrients that have a beneficial effect on health. Whey protein has been shown to increase lean body mass, improve glutathione status, have immunomodulatory effects and improve digestive health when combined with resistance training.

A healthy and balanced diet can be enhanced with whey protein either through whole food sources or occasional use of whey protein supplements.

How and when should you use whey protein?

There are no hard and fast rules for how and when you should use whey protein, as whey protein is essentially a food product, just like cheese and yogurt. However, there are some smart ways to use whey protein!

Whey protein is often used post-workout as it is quickly digested and has been shown to promote muscle protein synthesis and inhibit post-workout muscle protein breakdown. The typical amount consumed after training is between 20 and 40 grams.

You can achieve the same effect with lower doses, but these do not appear to maximize this effect and more than 40 grams will not significantly increase this effect. You can consume your whey protein mixed with water or milk after training. You can also prepare it with frozen fruit as a smoothie or add it to other foods to increase the protein content of your post-workout meal.

Whey protein can also be used as a protein source for a meal or as an on-the-go snack. For example, if you mix whey protein into your oatmeal in the morning, you can increase the protein content of your breakfast or you can take whey protein to work and drink it as a snack.

Side effects of whey protein

Whey protein can have a number of minor digestive side effects including constipation, bloating and a bloated feeling. People who are allergic to milk protein may experience allergic reactions after consuming whey protein and should therefore consult their doctor before consuming whey protein or if they experience any signs of allergic reactions.

As the lactose content of whey protein varies from product to product, people who suffer from lactose intolerance may experience intolerance symptoms. These people should use a high-quality isolate with the lowest possible lactose/carbohydrate content or avoid whey protein altogether.

Foods that contain whey protein

Dairy products such as milk, cheese, butter and yogurt contain whey protein. (Fun fact: the liquid that collects on a yogurt contains whey protein - so don't pour your gains down the sink!)

Whey protein is also used in the manufacture of industrially produced food products as it is a very versatile ingredient. It is often used as an emulsifier in baked products, in ice cream mixes and in dressings. It is also used to improve the solubility of preparations and can also be found in frozen desserts and even soups and sauces.

Typically, the amount contained in these products will not help you build muscle mass, but whey protein is almost certainly included.

Other protein sources compared to whey protein

Soy protein

Soyprotein is a protein source that is made from soybeans. The ability of soy protein to provide amino acids to the body's amino acid pool is well documented and it is considered a fast digesting protein. In addition, soy protein has been shown to increase muscle protein synthesis more than a placebo.

Unfortunately, soy protein appears to be an inferior protein source compared to whey protein. For example, consumption of 30 grams of whey protein or soy protein resulted in equivalent p70S6K phosphorylation (a molecule involved in protein synthesis) 2 hours after exercise, but soy protein, unlike whey protein, failed to maintain long-lasting phosphorylation of p70S6K for up to 4 hours after exercise.

In another study, the thermic effect of whey protein was 14.54% higher than that of soy protein, suggesting that whey protein is more suitable for weight loss. In the same study, the average maximum oxygen uptake was 29.94% for whey protein and only 23.98% for soy protein. Soy protein appears to be faster to digest, but may be inferior in terms of muscle protein synthesis.

Casein

Milk protein consists of whey protein and casein protein. Casein is often considered the "other" protein. Like whey protein, casein is a rich source of amino acids and provides a biologically complete amino acid profile.

Casein is digested more slowly than whey protein and therefore releases amino acids into the bloodstream over a longer period of time. This has led to the hypothesis that casein may be superior for muscle building as it provides a longer supply of amino acids, which is particularly useful when used in the evening before going to bed.

Although there are substantial claims regarding the superiority of casein, these do not stand up to closer scientific scrutiny. What we can really rely on, however, is that casein is probably a better choice than whey protein before going to bed, whereas whey protein is probably better after training.

From a weight loss perspective, casein may have a slight, albeit indirect, edge over whey protein. A potential advantage of casein over whey protein is that casein has a better satiating effect. As it is slower to digest, it often results in longer lasting satiety after consumption. This could help to reduce overall calorie intake and promote fat loss better than whey protein.

Whey protein compared to other types of protein

The two most popular methods for determining the quality/efficiency of a protein source are the biological value (BV) and the Protein Digestibility corrected Amino Acid Score (PDCAAS). Biological value refers to a practical measurement that determines the degree to which an animal is able to utilize the protein in question. It is calculated by analyzing nitrogen retention after consumption of the protein being tested.

The PDCAAS is a number between 0 and 1 and evaluates the protein quality based on its amino acid content relative to the human requirement for these amino acids. Basically, the higher the biological value or PCDAAS of a protein source, the better it can be used by the animal (yes, we humans are animals too). The table below gives an overview of the biological value and PDCAAS of various widely used protein sources:

Protein sources

Protein

BV

PDCAAS

Whey protein concentrates and isolates

104 to 159

1,00

Whole egg

100

1,00

Milk

91

1,00

Egg white

88

1,00

Cottage cheese

84

1,00

Tuna

83

?

fish

82

?

Beef

80

0,92

Chicken

79

?

Soy

74

0,91

Casein

71

1,00

Peanuts

68

0,52

Yoghurt

68

?

Oat flakes

58

0,57

Wheat

54

0,42

FAQ

How much whey protein should I use?

There is no real guideline for how much whey protein you should consume. Having said that, there are a few things you should consider. There seems to be a good case for aiming for 20 to 30 grams of whey protein post-workout to improve the muscle growth response after training. Some people will need more or less whey protein to optimize this, but there is no set value. The optimal amount will always depend on the type of protein, as the leucine content of the protein will determine the muscle growth response.

In the context of daily consumption, it would be wise to use whey protein as a supplement and not to cover the entire daily protein requirement with whey protein. 1 to 2 servings of whey protein per day would be a general guideline.

I suffer from lactose intolerance. Can I still use a whey protein supplement?

The degree of gastrointestinal reactions to whey protein can vary greatly from person to person. Typically, whey protein isolate contains the least amount of lactose and therefore has a lower likelihood of a person with any digestive discomfort reacting to this protein source. If you are unable to find a whey protein that is suitable for your individual lactose intolerance, then rice protein may be the next best alternative for you.

I am allergic to milk. Is a whey protein supplement safe and harmless for me?

The type of allergy to milk and the degree of allergic reaction to milk varies from allergy sufferer to allergy sufferer. If you are allergic to the milk proteins, then you may be able to consume hydrolyzed whey protein or pure whey protein isolate as this removes many of the allergenic compounds.

If you are lactose intolerant, you can try whey protein isolate, which is often virtually lactose free and is not a problem for many people who are lactose intolerant. It is of course wise to consult your doctor first and consume small portions of whey protein isolate or hydrolyzed whey protein and observe how your body reacts to it.

Is it true that whey protein is bad for the kidneys?

There is no scientific evidence that whey protein has any measurable negative effect on the kidneys in healthy people who have no history of kidney disease and have normal kidney function.

Is it true that whey protein is bad for my bones?

This is a good question. One of the most common arguments against high-protein diets - specifically high-protein diets that include a lot of animal protein - is that they are devastating to bone health. So let's take a look at what science has to say on the subject.

Did you know that high-protein diets increase calcium absorption in the digestive tract and that there is ample evidence to support the hypothesis that the increased intestinal calcium absorption of high-protein diets may actually improve bone health?

In a recently published paper by the leading scientists in the field of protein and bone health, the authors conclude "Recent epidemiologic, isotopic, and meta-analysis studies suggest that dietary protein synergistically interacts with calcium to improve calcium retention and bone metabolism.

The recommendation to reduce dietary protein intake to improve bone health is unwarranted and even potentially dangerous for individuals who consume inadequate amounts of protein." (64).

I think the idea that high-protein diets have a negative impact on bone health due to the net acid load has been adequately refuted. High-protein diets are not only safe for bone health, but may actually be very beneficial, especially for the elderly and those at risk for osteoporosis.

This has been my somewhat long-winded way of saying that whey protein is actually good for your bones!

Can I combine whey protein supplements with my other supplements in powder form such as creatine, glutamine, etc.?

Of course! You can mix creatine with your whey protein, whereas adding glutamine would be something of an overkill, as whey protein already contains a substantial amount of glutamine. Powdered greens are also an excellent addition, providing additional micronutrients.

Does it matter what liquid I use to mix my whey protein with?

Yes and no. The liquid will change the composition and texture of your shake. Water often results in a very thin shake, whereas milk makes the shake thicker and creamier.

From an absorption perspective, it could be argued that consuming whey protein with milk or other carbohydrates and sodium could increase the rate of absorption, but this is unlikely to make a large or even noticeable difference to the total amount of protein absorbed and its impact on muscle protein synthesis.

Does cooking or baking denature protein?

Yes, cooking or baking denatures the protein. However, this has virtually no effect on the muscle building capacity of the protein as this lies in the amino acids themselves. The denaturation process may reduce some of the bioactivity of the other components of whey protein, but this is not something worth worrying too much about.

Are there any dangers associated with consuming whey protein?

There are a few dangers associated with taking whey protein. The first is an allergic reaction to milk-based proteins. Some people are allergic to milk protein and these people may experience allergic reactions to whey protein.

There are also potential dangers if a whey protein is used from a non-reputable source or a company with poor quality control. Like any food product, whey protein can pose dangers if it is poorly manufactured or processed. However, these potential dangers are so insignificant that for most people the potential benefits far outweigh the risks.

Is whey protein safe for teenagers?

Based on the data currently available (and there is an almost obscene amount of research done on whey protein), there is no evidence that whey protein could be harmful to teenagers. It may even be beneficial for teenagers, as many of the components of whey protein support the body's growth.

Should women use whey protein differently to men?

There is no real reason why women should use whey protein differently to men. As women often weigh less than men, they may have a lower total daily protein requirement, which means they may need slightly less whey protein, but there are no specific needs for women in terms of how and when they should consume whey protein.

Should I only use whey protein isolate as it contains the highest amount of protein?

Whey protein isolate does indeed have the highest purity and the highest amount of protein per serving, making it an excellent choice for muscle building.

However, the production of whey protein isolate also filters out some of the other important bioactive compounds such as alpha-lactalbumin, beta-lactalbumin, immunoglobulins, glycomacropeptides and lactoferrin, to name but a few. So it might be a good idea to integrate both whey protein isolate and whey protein concentrate into your supplement program.

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Source: https://www.muscleandstrength.com/expert-guides/whey-protein

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How iron increases training performance in women
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How iron boosts exercise performance in women

Walk into any supplement store and you'll be overwhelmed by the variety of supplements available. There are dozens of brands, types and flavors of protein powders and many more pre-workout products, post-workout products, BCAA products, fat-burning products and sleep-enhancing products. You may not even know which ones are effective and which ones are a waste of money.

Here is one supplement that has proven its effectiveness: Iron. Research from the University of Melbourne has shown that iron is an important addition to your supplement program. In 2014, Australian scientists conducted a systematic analysis and review of studies on iron supplementation in women of childbearing age. Their research led to an intriguing conclusion: iron can help you perform at a higher efficiency and lower heart rate.

Women who were iron deficient or anemic at the beginning of the study showed the most visible results, but all women who used an iron supplement experienced a significant improvement in their physical performance. Thanks to the iron, the women were actually able to reach their maximum capacity (100% effort). But not only that, they saw an improvement in training efficiency even at sub-maximal levels. Simply put, they were able to push themselves harder, perform better and last longer.

Why is iron such an important supplement for training performance? It all boils down to the fact that iron plays an important role in the formation of new red blood cells. These red blood cells are responsible for the transportation of oxygen and nutrients through the bloodstream, as well as the removal of lactic acid (lactate) from the muscles. Thanks to this increase in oxygen and nutrients, which results from the increase in iron intake, you can improve your performance on the pitch, in the gym or on the cinder track.

If you're not giving what you'd like to in the gym or during your training sessions, then it's time you looked at your iron intake. According to this study, an iron deficiency can noticeably affect your training performance. An iron deficiency can lead to fatigue and lethargy - not to mention an increase in the risk of anemia.

"It can be useful to screen women - including women who train as elite athletes - for iron deficiency and ensure they receive appropriate prevention and treatment strategies. Athletes - especially women - are at increased risk of iron deficiency due to their diet and inflammation caused by excessive training," said lead researcher Dr. Sant-Rayn Pasricha from the Melbourne School of Population and Global Health.

References:

1. S.-R. Pasricha, M. Low, J. Thompson, A. Farrell, L.-M. De-Regil. "Iron Supplementation Benefits Physical Performance in Women of Reproductive Age: A Systematic Review and Meta-Analysis." Journal of Nutrition, 2014; DOI: 10.3945/jn.113.189589.

By Andy Peloquin

Source: https://breakingmuscle.com/fitness/how-iron-boosts-exercise-performance-in-women

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The effects of conjugated linoleic acid (CLA) in combination with resistance training
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The effects of conjugated linoleic acid (CLA) in combination with resistance training

This article is a summary of an interesting study published some time ago that examined the effects of conjugated linoleic acid(CLA) in conjunction with resistance training on the human body. This study is interesting because despite the fact that CLA has been used by countless bodybuilders and fitness athletes for over a decade, there have only been 2 studies looking at the interaction of CLA and training.

What is conjugated linoleic acid (CLA)?

Before we get to the actual study, here is a brief summary of conjugated linoleic acid to help bring all readers up to the same level of knowledge.

Conjugated linoleic acid (CLA) is a supplement designed to increase metabolic rate and fat utilization, and through the combination of these two effects, should result in weight loss. CLA is naturally found primarily in dairy products - but not in low-fat dairy products - and meat, particularly beef and lamb. The typical dietary intake is between 150 and 200 mg of CLA per day, while the usual dosage when using a CLA supplement is 3 to 5 grams per day, which is 20 to 40 times higher than the normal dietary intake.

Although CLA is a popular fat loss product, there is only a limited amount of scientific research to support its use. About half of these studies show that CLA can effectively support fat loss, while the other half show the opposite. If you are a rat, a cow or a pig, then CLA is likely to be quite effective for fat loss, while studies conducted with humans have not been particularly promising.

In this context, it should perhaps be mentioned that there are different forms of CLA, known as isomers, which have the same chemical formula but different structures. It could be that different isomers of CLA have different effects and could therefore produce different results.

The following study, published in the February 2006 issue of the Medicine and Science in Sports and Exercise Journal, examined the effects of CLA supplementation in conjunction with resistance training. The interesting thing about this study is that it was conducted with human subjects and therefore the question of whether the results are transferable to humans does not arise, as is the case with animal studies.

The effects of conjugated linoleic acid supplementation during resistance training

Craig Pinkoski, et al, Medicine and Science in Sports and Exercise, issue 38 (2), pages 339-348, 2006

The largest previous human study lasted 1 year and showed that CLA supplementation over this period reduced body fat mass in overweight subjects while slightly increasing lean body mass. Two other studies combined CLA with training and one of these studies showed that CLA was effective in reducing body fat, while the other found no changes in body composition.

So basically, we don't know anything about training and CLA. Furthermore, it's important to point out that the type of training in the two studies wasn't even specified, meaning it could have been anything from powerlifting to ballet.

Basically, this fact cries out for well-designed studies to be conducted to determine the true effects of CLA in combination with an exercise program. And that was exactly the purpose of this study - to determine the effects of CLA supplementation during a resistance training program.

The authors hypothesized that CLA, when combined with resistance training, would increase lean body mass and strength gains, reduce fat mass, increase resting metabolic rate, increase fat oxidation, and reduce urinary markers of muscle and bone loss compared to resistance training without CLA.

The subjects

This placebo-controlled, double-blind study involved 85 healthy men and women aged 18 to 45 years. All subjects were physically active at the time of the study, which is important as novice exercisers tend to achieve faster and greater results at the start of exercise.

The study lasted for a period of 7 weeks and included a periodized resistance training program that all subjects followed. The following variables were taken into account when evaluating the study:

  • Body weight
  • Body fat percentage
  • Fat-free body mass
  • Fat mass
  • Strength
  • Maximum torque during leg extension
  • Muscle thickness
  • Metabolic rate at rest
  • Respiratory exchange ratio
  • And some more...

In this article, only the variables that are important for this review of the study are considered.

The training program

The resistance training program consisted of 12 exercises chosen to work all major muscle groups. For each exercise, 3 to 4 sets of 4 to 10 repetitions were performed three times a week with approximately 75 to 90% of the maximum weight for one repetition (1RM weight). Basically, this was a fairly intensive training program.

To measure body composition, the scientists used a measuring device known as the Body Pod, which is more reliable than most other methods of determining body composition.

Maximum strength was determined using bench presses and squats.

After the actual study was completed, another study was conducted with a subset of the original 85 study participants. This follow-up study was a crossover study, meaning that the subjects switched groups after a break to ensure that all CLA had left the body. Subjects who were previously in the CLA group switched to the placebo group and subjects from the placebo group switched to the CLA group.

Results

A significant increase in lean body mass was observed in all male subjects, while no corresponding change was observed in women. However, no differences in total body mass were observed between the CLA and placebo groups over the course of the study.

However, there was a greater increase in lean body mass and a greater reduction in fat mass and body fat percentage in the CLA group compared to the placebo group. There was no significant difference between the CLA group and the placebo group in terms of average changes in body strength.

During the seven-week follow-up study, an increase in body mass, fat mass and body fat percentage was observed in the subjects in the placebo group, while no such increases were observed in the subjects in the CLA group.

It should also be mentioned at this point that there were no differences between the CLA group and the placebo group in terms of observed side effects, which is an indicator that CLA does not appear to have any significant side effects.

Conclusions

The main results of the seven-week study were that a significant increase in lean body mass and a reduction in body fat mass was observed in the CLA group. The authors noted that these changes, although significant, were relatively small in absolute terms, which calls into question their clinical relevance.

Nevertheless, the results are very interesting as this study is one of the few human studies to look at the relationship between CLA and resistance training. Longer studies are urgently needed to see if the trend seen in short studies is maintained over a longer period of time.

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