In recent years, pre-workout dietary supplements are almost as popular with gyms as protein. But just like protein supplements – and athletes – not every pre-workout product is the same, and every pre-workout product is not suitable for every athlete. Each has different ingredients in different dosages with different intended effects and could be suitable for different types of athletes with different goals.
Whether you want to hire a new PR, get a few more reps or just the most of your cardio can be a good pre-workout your ally.
In the following tutorial we will talk about how to choose the right pre-workout for you and how to make the most of it. Find out and be sure that your pre-workout will help you reach your fitness goals!
What is a Pre-Workout Addition?
Pre-workout supplements contain all the ingredients that humans contain with the unique goal of making their workouts more effective. The name literally means that you do something before a workout, a game or a match.
"In the hour before the workout, you should focus on preparing your inner environment for hard physical and mental work," explains Dwayne Jackson, in the article "The Science Behind the Best Pre- and Post-Workout Supps." "Therefore, pre-workout supplementation should optimize body and mind to maximize performance."
However, "optimization" can mean several things. In many cases, pre-workout supplements provide additional energy or concentration. But you can also convey certain physical benefits. For example, an athlete may appreciate the increased pain tolerance or power production that he provides during a full effort, such as a strong "big three" retry during Layne Norton's PH3 Power and Hypertrophy program. Another might appreciate the stamina to eliminate some more repetitions in high-volume DTP sets in Kris Gethin's 8-week hardcore trainer. Vasodilators and other ingredients can help increase blood flow to muscle tissue and increase recovery and endurance.
The most popular ingredients in today's popular pre-workouts include caffeine, beta-alanine, leucine or BCAAs, and nitric oxide boosters such as nitrosigines. Arginine or citrulline, all of which help to increase blood flow and increase the feeling of "pumping" during lifting. However, there are always new mixtures with new ingredients out.
Pre-workouts can be divided into two groups: those with stimulants and those without. The stimulants usually include caffeine in widely varying dosages, but other stimulants such as yohimbine, theacrine (Teacrine as the most common), guarana and many others may also be included. Many supplement companies have developed stimulant-free pre-workouts for those who are sensitive to caffeine, just do not want it, or who are just before bedtime.
If you are looking for a pre-workout that will make you feel on your feet and ready for action. You will not find enough there. However, if you do not want that, you still have the choice. And many pre-workouts fall into the middle, there is no more caffeine than a cup of tea or coffee.
For this reason, it is important to read labels, read numerous testimonials, and buy pre-workouts from established manufacturers. reputable companies.
Do Pre-Workout Supplements Work?
Honestly, it depends on what you take them for. Some people assume a pre-workout and think that they are getting bigger, stronger or faster. Probably not, but it certainly can help you destroy an important training. And if you crush many workouts over time, it can definitely help you get bigger, stronger, and faster! Remember that the main purpose of pre-workouts is not directly building muscle or improving your physique give you the energy, stamina and focus to perform the exercises that can help you achieve both goals.
There are numerous studies showing that most of the individual ingredients in today's most popular pre-workouts bring some strength, stamina or muscle growth. However, the training history and training of these subjects can be drastically different from yours.
Short answer: Yes, a pre-workout can help you have a better workout. But the truth is that it is only one factor of many. Make your workout right. Build up your nutritional basis. Optimize your rest with plenty of sleep. And then use additions to destroy the last 5 percent of the project!
What ingredients are in high quality pre-workouts?
The label on some pre-workouts just looks. In other cases it is a laundry list with difficult to pronounce words and mysterious "mixtures" or "matrices". And with so many different brands and products, it's hard to know what makes you better than the other.
Especially if you're just starting out, it's usually better to keep it simple. Here are four main ingredients to look for and how to help you train better:
Many lifters and other athletes consider caffeine to be their best training partner, and with good reason. "Post-study research has shown that caffeine can increase alertness, sharpen focus, increase tolerance to pain caused by exercise, burn fat, and help athletes to work longer periods in the gym and sports," writes Robert Wildman. Ph. D., RD, RISSN, in the article "Boost Your Training With Caffeine."
Caffeine gives you quick energy that you can use for both endurance training and shorter, high-intensity work such as lifting or sprinting. It has been shown to increase maximum strength, strength and endurance and even reduce muscle soreness .
Effective 😕 It is definitely. "In fact, caffeine works so well that its use was banned by the World Anti-Doping Agency until 2004," says Wildman.
Fortunately, the ban ended, and he notes, "More than 75 percent of elite athletes regularly use caffeine during the competition." And the rest of us too – over 80 percent of Americans consume caffeine daily!
Some people are caffeine-sensitive, regardless of dose, while others do not seem to notice the physiological effects. Research has also shown that you can build a tolerance to caffeine, although this tolerance can not affect the physical performance gains of caffeine [2,3]. Some people assume that they have built up a tolerance to the product they use, and just change the pre-workout every few months to see if only the "scene change" helps.
Please note that it is best for caffeine sensitive persons to avoid or limit caffeine intake after 4:00 pm. (assuming you are not a night worker), as this may affect sleep or sleep quality. For those who are caffeine-sensitive and work out at night, non-caffeinated products are probably the better option.
. 2 BCAAs or EAAs
Provided you get enough calories and protein, the branched-chain amino acids of leucine, isoleucine, and valine help you regulate protein metabolism. This means that protein synthesis is increased and protein degradation is reduced. In other words, BCAAs help build muscle and minimize muscle damage. Taken before exercise, they can also help reduce delayed muscle soreness (DOMS), so you can train hard faster, and reduce mental and physical fatigue during exercise. 
The most popular and scientifically proven ratio for BCAAs is 2: 1: 1 – two parts leucine to one part isoleucine and one part valine. They want more leucine because research has shown that it is the best amino acid in stimulating muscle protein synthesis. If the brand you are interested in does not indicate a ratio, look for at least 3 grams of leucine per serving.
All the benefits of BCAAs can also be achieved by taking essential amino acid mixtures (EAAs) which are becoming increasingly popular in pre-workouts and stand-alone amino blends. Finally, BCAAs are part of the EAAs. The EAAs include the three BCAAs and six other amino acids that your body can not produce on its own. For this reason, exercise physiologist Nick Coker has added EAAs 3 in his article "The Three Most Important Supplements for Gaining Mass"
Beta-Alanine is a staple of Pre-Workout with a unique purpose: it helps you to resist this "burning" feeling and do a few more repetitions to make the most of every sentence.
On the job In intense exercises, acid can accumulate in your body, increasing muscle fatigue and decreasing performance. Beta alanine binds with histidine to increase the concentration of the amino acid carnosine, which buffers the hydrogen ions that these acids form, which ultimately helps you maintain your intensity for a longer period of time. In other words, more volume; more profits.  In the article "Your Expert Guide to Beta-Alanine," supplementation specialist Chris Lockwood, CSCS, says, "It's probably the most effective, performance-enhancing supplement that has reached the sports nutrition market since creatine," saying "Beta alanine is one Ingredient I strongly recommended for athletes to keep in their arsenal. "
If you take a larger dose of beta-alanine, as is the case with many pre-workouts, you will most likely feel tingling , often on the neck and face. This is a condition called "paraesthesia". When someone does a pre-workout for the first time, they often notice it just like caffeine. Scientists are not sure why some people experience paraesthesia after taking beta-alanine, but it is harmless and transient.
However, the benefits of beta-alanine are associated with a catch: it must be consistently taken 2-3 weeks before the results begin to appear. Fortunately, you do not need to take beta-alanine just before training. If you take it in smaller doses throughout the day, this results in the training benefits with less tingling. The International Society for Sports Nutrition recommends a daily dose of 4-6 grams of beta-alanine, divided as needed. 
4. Nitric Oxide Boosters
These are the pre-workout ingredients that boost blood circulation in the muscles and help you get a powerful pump when lifting with high repetition.
L-arginine was once the most popular NO booster, but it's pretty rare these days. Today, there are many different ingredients that can help with NO production, but the most popular is probably the non-essential amino acid citrulline, either in the form of L-citrulline or citrulline malate.
L-Citrulline is the natural form of citrulline found in watermelons. It helps to increase the level of nitric oxide, which allows the blood vessels to be widened to get more oxygen and nutrients into the muscles. As nutritionist Mike Roussell, Ph.D., mentions in the article "Citrulline Malate: The Fatigue Fighter," it also plays a role in removing ammonia, a compound known to cause physical fatigue Your blood.  Citrulline malate is L-citrulline, to which malic acid or "malate" has been added. Apart from the increased blood flow caused by citrulline, it is believed that "Malate has its own fatigue-fighting capabilities, by supporting the body's ability to recycle sport-produced lactic acid and use it for energy production," notes Roussell. This one-two combination can mean improved endurance during exercise – more repetitions before failure – and even a decrease in muscle cancer. 
It seems as though every day a new pre-workout will start offering great potential and a scientifically supported dosage of ingredients. Some of the best known are:
- L-Tyrosine: For improved resistance to energy and fatigue
- L-Theanine: For more mental focus and to combat "jitters" that can accompany caffeine  Huperzine-A: For Mental Energy
- Yohimbine: For increased energy and mental intensity (Note that in some individuals the use of this natural alpha antagonist may cause anxiety.) 19659049] Nitrosigines : A Unique Form of Arginine for Increased Blood Flow, Reduced Muscle Damage, and Higher Concentration
- Beetroot Extract: For Endurance and Pumping
- Betaine: For Long-term Strength, Size and Recovery Profits  What about creatine? Many pre-workouts contain it, and it is not a disadvantage to take it before training. However, it is not demonstrably better at this time than any other. But more important than taking creatine is that you take it on a regular basis. In the article, "Five Reasons Why Your Creatine May Not Work," Krissy Kendall writes, "If you need to rely on your daily dose of creatine being given, you'll probably miss it." Instead, she recommends taking 3-5 grams of this low-cost power amplifier daily, in addition to what's in your pre-workout.
This is by no means an exhaustive list! If you see something new that you do not recognize in a pre-workout, make sure it's something you want to take. And buy pre-workouts only from well-established companies that do third-party testing and do not make out-of-the-box information.
When should I take a pre-workout? They often see people who drink their pre-workout while they go to the gym or even out of the locker room. This is a habit in the gym that you should not copy if you want yours to be as effective as possible!
This is the reason: "Most of the active ingredients in your pre-workout drink need 30 to 60 minutes to reach their highest level in your blood," writes Krissy Kendall in the article "3 Mistakes That Yours." Pre-workout. " "If you wait until you reach the gym, you will finish your second or third exercise before the full effects occur."
If you take your pre-workout earlier than 60-90 minutes, you still have enough energy to sustain a fairly long workout. Most pre-workouts contain caffeine, and it takes 3-5 hours for the body to halve caffeine levels in the blood. So long, a normal pre-workout can be termed "permanent" even though each caffeine metabolizes at different rates.
For this reason, it is equally important to take your pre-workout too late, especially if you are exercising in the late afternoon or early evening. Since many pre-workouts contain large amounts of caffeine, taking too late can damage your sleep. That's a big deal, as getting enough sleep is one of the most important factors for recovering from the hard work in the gym. Lack of sleep can even mean more body fat!
Then the question arises how often you should do a pre-workout. Many people pre-workout before almost every workout. The only downside of this approach is that it makes caffeine technically addictive, that it can become more tolerant, and that it has to accept increasing amounts in order to get the same energy boost.
Because of this, many coaches and athletes recommend saving a pre-workout for important, particularly intense workouts or routines that focus on larger muscle groups such as the legs, back, or chest.
Who should or should not have a pre-workout?
This is a complicated matter question! If you just go to the gym for a bit of sweat, a pre-workout can not bring much benefit. However, if you are someone who wants to turn serious training into serious results, a pre-workout can be helpful. For example, suppose you have four weeks ahead of Jim Stoppani, Ph.D.'s shortcut to shred program, and you know you need a boost to survive a cardiac acceleration day. You are hungry and sore, but the training must be completed! This is the mindset that leads many to the first pre-workout.
Anyone in the gym looking for an energy boost or an ambitious PR is the first candidate for a pre-workout supplement. Despite the best preparations in your sports bag, the best benefits over time are achieved through consistent training, continued use, adequate nutrition and adequate rest and recovery.
There's a good reason why Physiotherapist Krissy Kendall, Ph.D. ., contains the basic ingredients of pre-workout caffeine, BCAAs, citrulline malate and other NO boosters on their list of the "8 Best Supplements for Strengthers and Bodybuilders".
If you know you are high in caffeine, you may benefit more from a low-stimulation or stimulant-free pre-workout. Since many pre-workouts contain stimulants, some of which contain many stimulants, first ask your doctor if you have health problems that may cause side effects.
Parents should also be careful when giving a stim-heavy pre-workout for teens, and no, they are not a good idea for young kids. If your child is being trained seriously, tell them that they should be able to motivate themselves, go to the gym first, and work hard. The intensity-enhancing additions can come later, after building a solid foundation.
Can not I just have coffee or an energy drink before training?
A good point! A strong cup of tea or coffee or a can of your favorite energy drink definitely has the same performance-enhancing potential as a pre-workout. After all, caffeine is an indisputable powerhouse before training! It can increase stamina, strength and strength while reducing the feeling of fatigue. It can make you more alert, summon faster power, and help you concentrate during a difficult set.
A simple caffeinated drink is a one-dimensional solution, whereas a pre-workout is a multi-dimensional solution.
"When it comes to the particular challenges of hard training, you may lose yourself by using energy drinks alone," says exercise physiologist Nick Coker in his article "Transforming Your Energy Drink into a Pre-Workout Powerhouse." . "
If you use an energy drink instead of a pre-workout, Coker suggests adding extra amounts of important pre-workout ingredients like citrulline malate. And to be honest, if you're trying to get the most out of your workout, it's also a good idea to take a close look at what – if anything – is eaten in your pre-workout meal.
"While caffeine can help you crawl through the day without eating much, it has been shown to delay the fatigue of exercise when combined with carbohydrates," says Coker. "No matter what meal you choose, you aim for 35 grams of carbs and a total of at least 6 grams of essential amino acids or about 20 grams of high quality protein."
With some nourishment in the stomach, your muscles get training with the fuel they need to recover.
What if I'm sensitive to stimulants?
In a world full of people who can handle caffeinated drinks all day long, people who do not want or need caffeine can do so sometimes like second-class citizens. In the gym, however, you can have many of the same benefits as people who are trained before exercise. And as an added benefit, do not shake yourself so hard that the bar goes out of your hands.
Research has shown that genetics play a significant role in caffeine sensitivity: some people are severely affected, others are not affected at all, and some are in between. Whether you are very sensitive to caffeine, just do not like it, trying to break a pre-workout habit, or you are exercising late at night and do not want your sleep to be interrupted and non-stimulating pre-workouts offered Alternative.
If you're looking for one or two ingredients that might help your workout, physiologist Nick Coker calls these "The 4 Best Caffeine Free Supplements to Enhance Your Training."
- Citrulline malate: For increased blood flow and endurance
- Theacrine : For the same benefits of caffeine, without energy collapse or dependency problems (This ingredient is commonly referred to as Teacrine.)
- Alpha-GPC: A neurotransmitter prerequisite to help the nervous system maximize muscle activation.
- Betaine: For Long-Term Growth in Size and Power
At an incomplete end, a snack with lots of carbon can be the best pre-worko two hours before training, but you do not. If you get these calories and nutrients before exercise, you can get long lasting energy that can drive you even during long workouts. Avoid pre-workout snacks with lots of fiber and fat that take longer to digest, and some people may experience upset stomach when exercised intensively.
How can I prevent the feeling of uneasiness after a pre-workout?  Depending on how strong your pre-workout is and how your body responds to caffeine and other stimulants, some restless feelings may be inevitable. However, many pre-workouts today contain stimulants that are supposed to be "smoother" than pure caffeine like Theacrin, or have calming compounds to clear caffeine like "L-theanine".
Remember that the International Society for Sports Nutrition indicates that when dosing caffeine based on body weight the range for optimal effectiveness is 3 to 6 milligrams per kilogram or 1.3 to 2.7 milligrams per pound of body weight.  For a person weighing 150 pounds, this would be a range of 204 to 408 milligrams of caffeine. That's a big choice! Know where your pre fits before you take it, and if you've taken just 100 milligrams of caffeine at a time, do not jump right to 350 milligrams before an important workout.
That is, you can also take some control over the situation by paying more attention to your other diet before exercise.
"When you drink coffee on an empty stomach, you know the feeling: reckless, nervous, and sometimes even evil," explains Krissy Kendall, Ph.D., in the article "3 Mistakes You Make With Your Pre-Workout." "If you drink a pre-workout with 200-300 milligrams of caffeine without eating anything, you can feel the same way."
The answer, says Kendall, is to take your pre-workout meal as seriously as you treat your pre-workout supplement. "Taking a small meal 30-60 minutes before training can minimize side effects like these," she says. "In addition, these extra nutrients help you get your workout done."
Are Pre-Workouts Safe?
There is no doubt that some supplemental companies have been making headlines lately for the wrong reasons. And just about every lifter can tell you a story about the time he spent a strenuous pre-workout that was a bit more intense than expected. As long as you follow a few simple rules, you can complete a safe and productive workout after a pre-workout.
First of all, go with your eyes open! Know What You Take Make sure you buy your pre-workout from a reputable, well-established company, preferably one whose products have been tested and approved by an independent third party. Informed-Choice is such a test organization. Every year, Informed Choice checks about 18,000 samples for contamination by banned substances and to verify that what is on the label of your pre-workout exactly matches what's in the bottle.
If you know what you're taking, then the next step is to know yourself and why you're even doing a pre-workout. Is it a special advantage for your specific training, or is it just a way to motivate yourself for training? Do you feel comfortable with stimulants or do you know that you are feeling anxious and uncomfortable, or that you are struggling with insomnia? Is your training and diet alright, or do you hope a pre-workout will deliver magical results? Answer these questions before clicking "Buy" and remember that a pre-workout is just the icing on the cake. Train consistently and eat properly – these are the true keys.
Especially for young athletes there are no legal minimum limits for the use of pre-workouts or for other exercise-related supplements. Of course, a pre-workout for a teenage athlete may be "safe," but that does not mean it's necessary or even helpful. A teenager athlete or lifter would get more from just eating right and exercising regularly than from a particular dietary supplement – especially one that can cause a fast heart rate and other side effects that could impede otherwise potentially productive exercise.
And Whatever If you have problems with your heart, be sure to consult a doctor before taking any pre-workout or other preparation.
Are some pre-workouts better for women?
More women are in the gym Harder training than ever before means more women are taking dietary supplements than ever before. We think it is high time that this happened! However, there are certain supplements, such as pre-workouts, where the same rules and dosages that apply to an athlete are not always the best.
That's why: Research-recommended dosages of caffeine for athletic performance are generally based on body weight. The offer made by Douglas Kalman, Ph.D., RD, and co-founder of the International Society of Sports Nutrition in the Bodybuilding.com Foundations of Fitness Nutrition course, is personal at 3 to 6 milligrams per kilogram of body weight – and this 6 Milligrams are a serious dose that is not suitable for most people.
For a woman weighing 55 kilograms (or 120 pounds), this is a "I feel it, but not too much" 165 milligrams of caffeine at the bottom or a "My eyes out of my head" 330 milligrams at the top. And that's very different from a 200-pound bodybuilder! However, many popular pre-workouts contain a fixed scoop of 300 or more milligrams per serving, no matter how big you are.
This is not necessarily a problem, but it's worth remembering before you take a scoop a random pre-and maybe end up feeling that your heart beats out of your chest. Several companies on our list of the best women's pre-workouts make women-specific products whose body size is taken into account when dosing.
"I always say, start small and then go up from there, just to see how well your body tolerates it," says Krissy Kendall, Ph.D. in the Bodybuilding.com podcast episode "All About Caffeine: What Every Lifter Must Know." Translation: Try half a scoop or even less with popular pre-workouts to first measure your tolerance and then adjust the cans.
As far as the effectiveness of each ingredient in pre-workouts is concerned, this does not change simply because you use one or the other changing room. The increased energy, strength, endurance, and soreness that Jim Stoppani, the founder of the Shortcut to Size program, and others who believe that helping caffeine to improve exercise is just as true for women as it is for men. The same applies to common ingredients such as citrulline malate and beta-alanine.
In a recent support vote, a 2018 study published in the Journal of the International Society of Sports Nutrition confirms the fact that pre-workouts improve physical muscle endurance and anaerobic capacity [in women] while at the same time increasing the feeling of concentration after intense exercise. 
Sound familiar? Just determine what dose is working for you and try it yourself.
Can I take other supplements if I take pre-workouts?
Yes, of course! Pre-workout supplements are formulated with a specific purpose: to give you extra energy or stamina so you can attack your training with focus and purpose Other nutritional supplements are formulated to achieve other equally specific goals.
If For example, if you do not get enough protein in your diet, you will not be able to get consistent results from all of the world's pre-workouts. Eat up, and if you can not eat enough, take a shake after training or even your pre-workout. Workout.
On the other hand, if your pre-workout of your choice with certain ingredients is a bit too low there are many, it's okay to put it out with a little extra fzupeppen. Here are some points to consider:
- Beta Alanine: This ingredient needs to be taken almost daily to work effectively. Taking an extra 3 grams outside of your pre-workout is a breeze.  Creatine: Similar to beta-alanine, creatine should be taken daily for muscle recovery and other benefits.
- Nitric Oxide Boosters: Some companies make non-stimulating "pump" blends that can be stacked with a caffeinated pre-workout or energy drink.
If you are taking a caffeine pre-workout, be careful not to take other stimulants. The dose in most pre-workouts is strong enough without additional caffeine!
Should I buy or make my pre-workout supplement?
If you are someone who likes this extra control in your diet and supplementation, there is no reason why you can not do your own pre-workout. Well, scratch that, there are a few reasons: it can end up being a lot more expensive, and depending on how you make it, you can do without a few key ingredients. And the taste will probably be terrible … Yes, that's a pretty big challenge for the average athlete.
So before you put on a lab coat and get into PubMed, make sure you have a skirt. solid foundation for training and nutrition. Do you exercise consistently and in good shape 3-5 times a week? Do you eat enough calories and protein, and do you have a solid meal before exercise? Check, check, check. OK, then maybe you are no longer an "average" athlete.
However, before you search the dark web for a discounted range of pure African yohimbine, you should keep in mind that starting with simplicity is almost always the best option. If you want to make your own pre-preparation, you should keep the key ingredients for the best pre-workout: caffeine (if that's your concern), beta-alanine, and possibly nitric oxide boosters for stamina and pumping. If you want to penetrate the rabbit hole with nootropics (such as brain enhancing supplements) or other target-specific ingredients, you should do so – but do not expect magic. process
. It's just about improving what you can do with it!
- Goldstein, ER, Ziegenfuss, T., Kalman, D., Kreider, R., Campbell, B., Wilborn, C.,. .. & Wildman, R. (2010). International Sports Nutrition Society stands for Caffeine and Performance. Journal of the International Society of Sports Nutrition, 7 (1), 5.
- Overstreet, D.S., Penn, T.M., Cable, S.T., Aroke, E.N. & Goodin, B.R. (2018). Higher consumption of habitual caffeine in the diet is associated with lower experimental sensitivity to pain in a community-based sample. Psychopharmacology 1-10.
- Bowtell, JL, Mohr, M., Fulford, J., Jackman, SR, Ermidis, G., Krustrup, P., & Mileva, KN (2018). , Improved Training Tolerance to caffeine is associated with the modulation of both peripheral and central neuronal processes in human participants. Frontiers in Nutrition, 5, 6.
- Shimomura, Y., Inaguma, A., Watanabe, S., Yamamoto, Y., Muramatsu, Y., Bajotto, G., … & Mawatari, K. (2010). Amino acid supplementation before squatting and delayed soreness. International Journal of Sports Nutrition and Motor Metabolism, 20 (3), 236-244.
- Smith, AE, Walter, AA, Graef, JL, Kendall, KL, Moon, JR, Lockwood, CM, … & Stout, JR (2009). Effects of B-alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind study. Journal of the International Society of Sports Nutrition, 6 (1), 1-9
- Trexler, ET, Smith-Ryan, AE, Stout, JR, Hoffman, JR, Wilborn, CD, Sale, C ., … & Campbell, B. (2015). International Sports Nutrition Society: Beta Alanine. Journal of the International Society of Sports Nutrition, 12 (1), 30.
- Pérez-Guisado, J. & Jakeman, P.M. (2010). Citrulline malate improves athletic anaerobic performance and relieves muscle soreness. The Journal of Strength & Conditioning Research, 24 (5), 1215-1222.
- Cameron, M., Camic, CL, Doberstein, S., Erickson, JL, & Jagim, AR (2018)). The acute effects of a multi-ingredient pre-workout supplement on resting energy expenditure and exercise performance in relaxed women. Journal of the International Society of Sports Nutrition, 15 (1), 1.