A: The literature supports roughly 0.8-1 gram per pound of bodyweight in young adults. Can you eat more? As long as you have healthy, functioning kidneys, yes. Will you receive any further physiological benefit from it? Most likely, no. Not only that, since our calories are set, if we choose to overconsume protein then we must reduce either carbohydrates and/or fat in order to keep caloric expenditure within our set range. Once protein needs are met (~0.8-1g/lb of bodyweight) you will likely see greater benefits from higher carbohydrate consumptions given the influence they have on anabolism and the anaerobic energy pathway. However, as I mentioned above, these recommendations will differ for older trainees given the blunted anabolic response from the ingestion of amino acids. 
When it comes to building muscle, your body only knows or cares about the tension, fatigue and damage an exercise is generating… not the type of equipment you were using when performing that exercise. It really couldn’t give the slightest crap about that. For this reason, ALL types of exercises and ALL types of equipment are capable of stimulating muscle growth.
Using too much weight, too soon; always start lower than your expected ability and work your way up that first workout. If your form suffers, you are swinging the weight, or using momentum, this indicates you may be using too much weight. Greater momentum increases the potential for injury and reduces the effectiveness to the muscle group being targeted.
Creatine levels in the blood tend to return to baseline (after a loading with or without the maintenance phase) after 28 days without creatine supplementation.[152][200][201] This number may vary slightly from one individual to another, and for some may exceed 30 days.[202] Assuming an elimination rate of creatinine (creatine’s metabolite) at 14.6mmol per day,[35][201] six weeks of cessation is approaching the upper limit for serum creatine to completely return to baseline.
It is suggested [16,37] that another mechanism for the effect of creatine could be enhanced muscle glycogen accumulation and GLUT4 expression, when creatine supplementation is combined with a glycogen depleting exercise. Whereas it has been observed [38] that creatine supplementation alone does not enhance muscle glycogen storage. Hickner et al [15] observed positive effects of creatine supplementation for enhancing initial and maintaining a higher level of muscle glycogen during 2 hours of cycling. In general, it is accepted that glycogen depleting exercises, such as high intensity or long duration exercise should combine high carbohydrate diets with creatine supplementation to achieve heightened muscle glycogen stores [39].
Those micro-tears that are such a key factor for muscle-building need rest to rebuild themselves and grow stronger. When do they do that? When you’re asleep! “You have to rest and feed your muscles between workouts or you will tear them down and they will become weaker,” says Olson. “Over time, you run the risk of over-training, which can result in injury, and possibly even more sleep troubles.”
^ Jump up to: a b c d e Cooper R, Naclerio F, Allgrove J, Jimenez A (July 2012). "Creatine supplementation with specific view to exercise/sports performance: an update". Journal of the International Society of Sports Nutrition. 9 (1): 33. doi:10.1186/1550-2783-9-33. PMC 3407788. PMID 22817979. Creatine is produced endogenously at an amount of about 1 g/d. Synthesis predominately occurs in the liver, kidneys, and to a lesser extent in the pancreas. The remainder of the creatine available to the body is obtained through the diet at about 1 g/d for an omnivorous diet. 95% of the bodies creatine stores are found in the skeletal muscle and the remaining 5% is distributed in the brain, liver, kidney, and testes [1].

Bottom Line: Con-Cret is one of the best creatine HCI products available. Its unique use of creatine HCI allow it to offer all the great benefits of creatine, without the bloating and water retention that creatine monohydrate sometimes causes – making Con-Cret a good creatine to take if you’re concerned about the potential for bloating with other products.
Creatine is marketed as "nature's muscle builder" and "the most legitimate sports supplement around." Professional and amateur athletes alike are gobbling up this alleged ergogenic aid, hoping to increase their strength and performance. Creatine supplementation is claimed to increase muscle power by playing a role in the transfer of energy to help the muscle contract. Supplement labels state that "creatine is converted to phosphocreatine, which is important for short energy bursts such as sprinting and weight lifting" and that "depletion of phosphocreatine can result in muscle fatigue and fading muscle power." Claims are also made that supplementation increases muscle body mass.
Different forms of creatine in combination with other sports supplements as well as varying doses and supplementation methodology should continue to be researched in an attempt to understand further application of creatine to increase sports and exercise performance of varying disciplines. It is important to remain impartial when evaluating the safety of creatine ingested as a natural supplement. The available evidence indicates that creatine consumption is safe. This perception of safety cannot be guaranteed especially that of the long term safety of creatine supplementation and the various forms of creatine which are administered to different populations (athletes, sedentary, patient, active, young or elderly) throughout the globe.
All possible measures have been taken to ensure accuracy, reliability, timeliness and authenticity of the information; however Onlymyhealth.com does not take any liability for the same. Using any information provided by the website is solely at the viewers’ discretion. In case of any medical exigencies/ persistent health issues, we advise you to seek a qualified medical practitioner before putting to use any advice/tips given by our team or any third party in form of answers/comments on the above mentioned website.
Our bodies store creatine in our muscles so that we have quick access to it for fast, high-intensity movements, like sprinting or powerlifting, explains Autumn Bates, a certified clinical nutritionist and sports nutritionist in private practice in Manhattan Beach, California. “It's a nonessential amino acid, meaning your body creates it and you don't need to primarily get it from food.”
You don’t have to, but you can. The typical creatine dose is 5 grams once or twice per day, but it’s sometimes suggested that one should “load” creatine by taking 20 to 25 grams per day for the first week of usage. This is then followed with 3 to 4 weeks of 5 grams per day, then a break for a week or two, then repeat. This may bring about more acute increases in strength and muscle size — creatine will “work” more quickly, in other words — but it’s not necessary.

After the ingestion of 5g creatine in otherwise healthy humans, serum levels of creatine were elevated from fasting levels (50-100µM) to 600-800µM within one hour after consumption.[135] The receptor follows Michaelis-Menten kinetics with a Vmax obtained at concentrations higher than 0.3-0.4mmol/L,[136] with prolonged serum concentrations above this amount exerting most of its saturation within two days.[137]
Creatine pyruvate (also known as creatine 2-oxopropanoate) in an isomolar dose relative to creatine monohydrate has been shown to produce higher plasma levels of creatine (peak and AUC) with no discernible differences in absorption or excretion values.[83] The same study noted increased performance from creatine pyruvate at low (4.4g creatine equivalence) doses relative to citrate and monohydrate, possibly due to the pyruvate group.
But one question has repeatedly popped up: When is the best time to take creatine? Recent research has suggested that there might be an ideal time. That’s when I decided to speak with the supplement experts at Examine.com. For those of you who don’t know, they have created the world’s largest database of facts about supplements. No marketing BS. Just a bunch of Ph.D’s, PharmD’s, and biomedical researchers who are obsessed with sharing the truth. Their Supplement Guide is the best thing written about supplements since…well…ever. If you’ve ever had a question it’s pack with research and fact-based information to help you make healthier supplement choices.
One pilot study using 150mg/kg creatine monohydrate for a five day loading phase followed by maintenance (60mg/kg) for the remainder of the five weeks noted that supplementation was associated with fewer muscle symptoms and complaints alongside improved muscular function,[572] yet a later trial trying to replicate the obsevations using 150mg/kg daily for five weeks noted the opposite, that creatine supplementation exacerbated symptoms.[573] 
Increasing creatine levels in skeletal muscle to 687% of baseline (0.5mM creatine, thought to be equivalent to 5g creatine[135]) doesn’t seem to per se increase glucose uptake, but increases glucose oxidation (140% of baseline)[341] which is due to a two-fold increase in the activity of α1 and α2 subunits of AMPK, a potency comparable to 1mM of the reference drug AICAR.[341] Glucose uptake associated with AMPK has indeed been noted in diabetic people who are undergoing physical exercise[342] and in contracting skeletal muscle cells,[153][330] but according to rat[343][344][345] and in vitro studies of cells not being contracted,[341] this is not a per se effect of non-exercising tissue but an augmentation of exercise-induced glucose uptake.

Creatine is not an essential nutrient[19] as it is naturally produced in the human body from the amino acids glycine and arginine, with an additional requirement for methionine to catalyze the transformation of guanidinoacetate to creatine. In the first step of the biosynthesis these two amino acids are combined by the enzyme arginine:glycine amidinotransferase (AGAT, EC:2.1.4.1) to form guanidinoacetate, which is then methylated by guanidinoacetate N-methyltransferase (GAMT, EC:2.1.1.2), using S-adenosyl methionine as the methyl donor. Creatine itself can be phosphorylated by creatine kinase to form phosphocreatine, which is used as an energy buffer in skeletal muscles and the brain.
According to BodyBuilding.com, adenosine triphosphate (ATP) is made up of a nucleotide bonded to three phosphate groups. When one of those phosphate groups is cleaved from the ATP molecule, a lot of energy is made available. That energy is used to fuel chemical reactions in cells, and ATP becomes adenosine diphosphate (ADP). Creatine enables the release of energy from stored ATP and is converted to creatinine.

One pilot study using 150mg/kg creatine monohydrate for a five day loading phase followed by maintenance (60mg/kg) for the remainder of the five weeks noted that supplementation was associated with fewer muscle symptoms and complaints alongside improved muscular function,[572] yet a later trial trying to replicate the obsevations using 150mg/kg daily for five weeks noted the opposite, that creatine supplementation exacerbated symptoms.[573] 
Weight training is a common type of strength training for developing the strength and size of skeletal muscles. It utilizes the force of gravity in the form of weighted bars, dumbbells or weight stacks in order to oppose the force generated by muscle through concentric or eccentric contraction. Weight training uses a variety of specialized equipment to target specific muscle groups and types of movement.

It is suggested [16,37] that another mechanism for the effect of creatine could be enhanced muscle glycogen accumulation and GLUT4 expression, when creatine supplementation is combined with a glycogen depleting exercise. Whereas it has been observed [38] that creatine supplementation alone does not enhance muscle glycogen storage. Hickner et al [15] observed positive effects of creatine supplementation for enhancing initial and maintaining a higher level of muscle glycogen during 2 hours of cycling. In general, it is accepted that glycogen depleting exercises, such as high intensity or long duration exercise should combine high carbohydrate diets with creatine supplementation to achieve heightened muscle glycogen stores [39].
Researchers found that 5g of creatine four times daily for a week (loading) before sleep deprivation for 12-36 hours was able to preserve cognition during complex tasks of executive function at 36 hours only, without significant influence on immediate recall or mood.[279] A similar protocol replicated the failure to improve memory and attention, but noted less reports of fatigue (24 hours) and less decline of vigor (24 hours) although other mood parameters were not measured.[276]
Creatine is vital for brain function, which has mechanisms to take up creatine, as well as regulate its intake. Although the diet appears to be the major source of creatine (and thus lack of dietary intake could cause a non-clinical deficiency) excess levels of creatine do not appear to “super-load” the brain similar to muscle tissue. Due to kinetics, creatine appears to be more “preventative” or acts to restore a deficiency in the brain. This is in contrast to creatine effects in muscle cells, where it can affect performance substantially on an acute timescale.
Drink plenty of water throughout the day, especially in the hours leading up to your workout. This can help you feel full and reduce hunger pangs. During training, drink about 8 ounces every 15-20 minutes, more when it's hot and humid. The reason is simple: Your performance quickly begins to suffer when the body is dehydrated just 1%-–2%. And if you wait till you feel thirsty, you've waited too long. A flavorful, low-calorie sports drink is a great way to hydrate. Try drinking fluids stored at cooler temperatures; studies show that people consume more when the liquid is colder.
Do a single set of repetitions. Theories on the best way to approach weight training abound, including countless repetitions and hours at the gym. But research shows that a single set of exercise with a weight that fatigues your muscle after about 12 to 15 repetitions can build muscle efficiently in most people and can be as effective as three sets of the same exercise.
Do Belgian squats (or "single leg squats") with a dumbbell. Hold out in front of your chest a dumbbell using both hands. Standing in front of a bench, lift your right leg back so that it's parallel to the floor and resting comfortably on the bench. Bend into a squat using the left leg, so that the right knee almost hits the floor. Lift and repeat 3 x 8. Repeat using opposite leg.
D-aspartic acid can also help to reduce cortisol levels. Cortisol is known as the “stress” hormone because its production increases during stressful situations. High cortisol levels can have many negative side effects, such as weight gain, muscle tissue breakdown, or increased blood sugar. Taking a supplement that includes cortisol can reduce stress and prevent excess fat storage or muscle loss.
It raised the question about performance-enhancing drugs. Their murky role in bodybuilding has long shrouded the sport. A 2013 documentary on Heath and Mr. Olympia called “Generation Iron” (a sort of bookend piece to 1977’s “Pumping Iron,” which launched Schwarzenegger and others to fame) called the topic “taboo.” It then insinuated that, of course, bodybuilders competing in top-level contests like Mr. Olympia use steroids.
One pilot study using 150mg/kg creatine monohydrate for a five day loading phase followed by maintenance (60mg/kg) for the remainder of the five weeks noted that supplementation was associated with fewer muscle symptoms and complaints alongside improved muscular function,[572] yet a later trial trying to replicate the obsevations using 150mg/kg daily for five weeks noted the opposite, that creatine supplementation exacerbated symptoms.[573]  

Of course, cardio is an important part of fitness too, but the benefits of strength training are major. Strength training helps build muscle, and lean muscle is better at burning calories when the body is at rest, which is important whether you're trying to lose weight or maintain it. It also helps strengthens joints and bones, avoid injury, improve your muscular endurance, and will help you give it your all during your other workouts, whether that means setting a new PR if you're a runner or pushing (and pulling) a little harder with your legs during your favorite indoor cycling class.
The basic principles of weight training are essentially identical to those of strength training, and involve a manipulation of the number of repetitions (reps), sets, tempo, exercise types, and weight moved to cause desired increases in strength, endurance, and size. The specific combinations of reps, sets, exercises, and weights depends on the aims of the individual performing the exercise.
Supplementation of creatine at 5g daily alongside rehabilitation (after limb immobilization for two weeks while taking 20g daily) is associated with a preservation in GLUT4 levels, which were reduced during immobilization. During exercise rehabilitation, it increased to 40% above placebo.[330] This study failed to note an increase in GLUT4 in control, despite exercise normally doing so.[331][332] This effect is thought to be the result of the low frequency of activity. Thus, creatine was thought to augment the increase (insignificant due to low exercise) to significant levels.[330] In other studies, creatine was found to increase GLUT by approximately 30% relative to control, but this effect failed to reach statistical significance. This study did not issue an exercise protocol.[207]
Most weightlifters, athletes and bodybuilders know about creatine. They know it’s an important substance to take to give you an important edge in your workouts. Kaged Muscle made two different creatine products to give you the purest edge possible. They’re known as Kaged Muscle C-HCL Powder. There is a powder version and a capsule version. Keep Reading »

Listen, I know in the beginning of this post I was sympathetic to your problem, but I am also here to say, Suck It Up. I can tell you that to gain weight, you need to focus on making your meals a habit rather than an afterthought. Your body is pre-programmed with your genetic disposition. And in your case, you have a very fast metabolism that digests and burns calories quickly. Focus on having 5-6 calorie-dense meals a day spaced 2-3 hours apart so that your body is constantly being provided with something to metabolize and build muscle.


We’ll be talking more about this later, but for now, just give it a shot! In strength training you can see your progress so clearly that as you can do more and more, you’ll also be rewarded by seeing your strength progress from level 1 to level 50! If you aren’t a fan of the downtime, put on a book on tape or throw on your favorite playlist while circuit training to ensure you’re always moving (instead of sitting and waiting in between sets).
These supplements can vary considerably from product to product in ingredients, serving sizes, and more. But the goal of each of them is generally quite similar. Most bodybuilding supplements are designed to help stimulate new muscle growth, cut away excess fat, and improve the recovery process so that you can get the most out of each trip to the gym.
Heath bent his legs — each thigh about 32 inches around, bigger than his waist — and lifted the black case. Inside was his latest Mr. Olympia trophy. In bodybuilding, it is called the Sandow, and Heath has won the last six, most recently in Las Vegas in September. Arnold Schwarzenegger, still the world’s most famous bodybuilder, won six in a row, too, and then a seventh a few years later. Two men, Lee Haney and Ronnie Coleman, have won eight.

There are several different available forms of creatine: creatine anhydrous which is creatine with the water molecule removed in order to increase the concentration of creatine to a greater amount than that found in CM. Creatine has been manufactured in salt form: creatine pyruvate, creatine citrate, creatine malate, creatine phosphate, magnesium creatine, creatine oroate, Kre Alkalyn (creatine with baking soda). Creatine can also be manufactured in an ester form. Creatine ethyl ester (hydrochloride) is an example of this, as is creatine gluconate which is creatine bound to glucose. Another form is creatine effervescent which is creatine citrate or CM with citric acid and bicarbonate. The citric acid and bicarbonate react to produce an effervescent effect. When mixed with water the creatine separates from its carrier leaving a neutrally charged creatine, allowing it to dissolve to a higher degree in water. Manufacturers claim that creatine effervescent has a longer and more stable life in solution. When di-creatine citrate effervescent was studied [59] for stability in solution it was found that the di-creatine citrate dissociates to citric acid and creatine in aqueous solutions which in turn forms CM and eventually crystallises out of the solution due to its low solubility. Some of the creatine may also convert to creatinine.


Extracellular creatine (creatine outside of a cell) appears to influence creatine uptake into a cell. It seems that prolonged and excessive levels of creatine actually suppress uptake (a form of negative regulation to prevent excessive influx).[180] In vitro studies in rat muscle cells have shown that including 1mM creatine into cell culture medium substantially reduces creatine uptake into cells. The inhibitory effect was partially negated by protein synthesis inhibitors, suggesting that high levels of creatine induce the expression of a protein that suppresses creatine transporter activity.[180] Similar findings were reported in a later study in cultured mouse myoblasts, which noted a 2.4-fold increase in intracellular creatine levels in the presence of the protein synthesis inhibitor cyclohexamide.[174]
You don’t have to, but you can. The typical creatine dose is 5 grams once or twice per day, but it’s sometimes suggested that one should “load” creatine by taking 20 to 25 grams per day for the first week of usage. This is then followed with 3 to 4 weeks of 5 grams per day, then a break for a week or two, then repeat. This may bring about more acute increases in strength and muscle size — creatine will “work” more quickly, in other words — but it’s not necessary.
After supplementation of creatine monohydrate (loading phase, followed by 19 weeks maintenance), creatine precursors are decreased by up to 50% (loading) or 30% (maintenance), which suggests a decrease in endogenous creatine synthesis during supplementation.[38] This appears to occur through creatine’s own positive feedback and suppression of the l-arginine:glycine amidinotransferase enzyme, the rate-limiting step in creatine synthesis, as levels of intermediates before this stage are typically elevated by up to 75%.[38]
Mercimek-Mahmutoglu, S., Stoeckler-Ipsiroglu, S., Adami, A., Appleton, R., Araujo, H. C., Duran, M., Ensenauer, R., Fernandez-Alvarez, E., Garcia, P., Grolik, C., Item, C. B., Leuzzi, V., Marquardt, I., Muhl, A., Saelke-Kellermann, R. A., Salomons, G. S., Schulze, A., Surtees, R., van der Knaap, M. S., Vasconcelos, R., Verhoeven, N. M., Vilarinho, L., Wilichowski, E., and Jakobs, C. GAMT deficiency: features, treatment, and outcome in an inborn error of creatine synthesis. Neurology 8-8-2006;67(3):480-484. View abstract.
Heart Failure is one of the single most common complications that face many people today. When a heart ages, the cells collect a yellow-brown layer which is waste and can lead to heart complications. This process is known as lipofuscin, or “aging pigment” which leads to death opposed to someone who can delay that as far as possible. [3] In mice, a study was performed where two groups of mice who had lipofuscin underwent different experiments, one group received creatine supplementation, and one group did not receive supplementation. What they found was that the mice who supplemented creatine lived 9% longer than the ones who did not receive creatine. 9% translated into human years results in almost 7 years, which could suggest that if you suffer from this deterioration, creatine supplementation could potentially increase your longevity by 7 years. [3]

Bodybuilders spend years and years of their lives focused on perfecting the human body through proper training and nutrition. You, on the other hand, might not have an interest in the sport of bodybuilding, but do want to know the secrets to six-pack abs, a wide back, and rounded shoulders. And what better place to score the tricks of the trade than from 3-time Mr. Olympia Phil Heath. 


While muscle growth is critical for bodybuilding, getting rid of extra fat is a necessity to improve your total physique. These supplements can help to increase your metabolism, forcing your body to burn away more of its fat stores. They can also slow down the digestion process to prevent excess fat and carbohydrates from entering the body and being stored.
When looking specifically at human studies, there has been a failure of creatine supplementation to induce or exacerbate kidney damage in people with amyotrophic lateral sclerosis (ALS). Subjects do not experience kidney damage for up to or over a year’s worth of supplementation in the 5-10g range.[505][506][507] Postmenopausal women,[517] people with type II diabetes,[518] people on hemodialysis,[313] otherwise healthy elderly,[519] young people,[454][520][521] and athletes do not experience kidney damage either.[324] Moreover, numerous scientific reviews on both the long- and short-term safety of supplemental creatine have consistently found no adverse effects on kidney function in a wide range of doses.[522][523][524][452][525][451][526][527] However, while doses >10 g/day have been found not to impair kidney function, there are fewer long-term trials using such high chronic daily intakes.[527]
In the last week leading up to a contest, bodybuilders usually decrease their consumption of water, sodium, and carbohydrates, the former two to alter how water is retained by the body and the latter to reduce glycogen in the muscle. The day before the show, water is removed from the diet, and diuretics may be introduced, while carbohydrate loading is undertaken to increase the size of the muscles through replenishment of their glycogen. The goal is to maximize leanness and increase the visibility of veins, or "vascularity". The muscular definition and vascularity are further enhanced immediately before appearing on stage by darkening the skin through tanning products and applying oils to the skin to increase shine. Some competitors will eat sugar-rich foods to increase the visibility of their veins. A final step, called "pumping", consists in performing exercises with light weights or other kinds of low resistance (for instance two athletes can "pump" each other by holding a towel and pulling in turn), just before the contest, to fill the muscles with blood and further increase their size and density.
The lower the rep range (and therefore the higher the intensity and the heavier the weight), the more rest there should be between sets. So most of the time, exercises being done in the 5-8 rep range need longer rest periods than exercises being done in the 8-10 rep range, which need longer rest periods than exercises being done in the 10-15 rep range.
Gordon, P. H., Cheung, Y. K., Levin, B., Andrews, H., Doorish, C., Macarthur, R. B., Montes, J., Bednarz, K., Florence, J., Rowin, J., Boylan, K., Mozaffar, T., Tandan, R., Mitsumoto, H., Kelvin, E. A., Chapin, J., Bedlack, R., Rivner, M., McCluskey, L. F., Pestronk, A., Graves, M., Sorenson, E. J., Barohn, R. J., Belsh, J. M., Lou, J. S., Levine, T., Saperstein, D., Miller, R. G., and Scelsa, S. N. A novel, efficient, randomized selection trial comparing combinations of drug therapy for ALS. Amyotroph.Lateral.Scler. 2008;9(4):212-222. View abstract.
During the 1950s, the most successful and most famous competing bodybuilders[according to whom?] were Bill Pearl, Reg Park, Leroy Colbert, and Clarence Ross. Certain bodybuilders rose to fame thanks to the relatively new medium of television, as well as cinema. The most notable[according to whom?] were Jack LaLanne, Steve Reeves, Reg Park, and Mickey Hargitay. While there were well-known gyms throughout the country during the 1950s (such as Vince's Gym in North Hollywood, California and Vic Tanny's chain gyms), there were still segments of the United States that had no "hardcore" bodybuilding gyms until the advent of Gold's Gym in the mid-1960s. Finally, the famed Muscle Beach in Santa Monica continued its popularity as the place to be for witnessing acrobatic acts, feats of strength, and the like. The movement grew more in the 1960s with increased TV and movie exposure, as bodybuilders were typecast in popular shows and movies.[citation needed]
Another favorite bodybuilding supplement, creatine is an amino acid found in the body. The highest levels of this molecule are in your muscles and brain. It is made by your liver, pancreas and kidneys, but is also found in foods including meat, eggs and fish. Research has shown that it may help athletes including weightlifters who need short bursts of energy (5). In this study, creatine monohydrate proved to be an effective muscle builder. It works to improve body composition, muscle mass, strength and power.  Note that it was also more effective than other forms of creatine. How does it do this?
Stand on one foot with the arch and heel hanging off of the edge of a step or platform. Hold onto something if you need help balancing. Drop your heel all the way down below the step, and then rise all the way up on your toes. Hold dumbbells to make it harder. If you can balance without holding on to something, you’ll work your core muscles, too. You'll also build more stable joints in the other leg.
This period also saw the rise of anabolic steroids in bodybuilding and many other sports. In bodybuilding lore, this is partly attributed to the rise of "mass monsters", beginning with Arnold Schwarzenegger, Sergio Oliva, and Lou Ferrigno in the late 1960s and early 1970s, and continuing through the 1980s with Lee Haney, the 1990s with Dorian Yates, Ronnie Coleman, and Markus Rühl, and up to the present day. Bodybuilders such as Greg Kovacs attained mass and size never seen previously but were not successful at the pro level. Others were renowned for their spectacular development of a particular body part, like Tom Platz or Paul Demayo for the leg muscles. At the time of shooting Pumping Iron, Schwarzenegger (while never admitting to steroid use until long after his retirement) said that "you have to do anything you can to get the advantage in competition".[citation needed] He would later say that he does not regret using anything.[8]
Weight training is primarily an isotonic form of exercise, as the force produced by the muscle to push or pull weighted objects should not change (though in practice the force produced does decrease as muscles fatigue). Any object can be used for weight training, but dumbbells, barbells, and other specialised equipment are normally used because they can be adjusted to specific weights and are easily gripped. Many exercises are not strictly isotonic because the force on the muscle varies as the joint moves through its range of motion. Movements can become easier or harder depending on the angle of muscular force relative to gravity; for example, a standard biceps curl becomes easier as the hand approaches the shoulder as more of the load is taken by the structure of the elbow. Originating from Nautilus, Inc., some machines use a logarithmic-spiral cam to keep resistance constant irrespective of the joint angle.

In humans, studies that investigate links between serotonin and creatine supplementation find that 21 trained males, given creatine via 22.8g creatine monohydrate (20g creatine equivalent) with 35g glucose, relative to a placebo of 160g glucose, was found to reduce the perception of fatigue in hot endurance training, possibly secondary to serotonergic modulation, specifically attentuating the increase of serotonin seen with exercise (normally seen to hinder exercise capacity in the heat[233]) while possibly increasing dopaminergic activity (conversely seen to benefit activity in the heat[234]).[155]
×