Spero Karas, MD, assistant professor of orthopaedics in the division of sports medicine at Emory University, says that testosterone, the male hormone responsible for muscle growth, maxes out between the ages of 16 and 18. It reaches a plateau during the 20s and then begins to decline. As a result, muscle building after the adolescent years can be challenging, he says.
Carducci, C., Birarelli, M., Leuzzi, V., Carducci, C., Battini, R., Cioni, G., and Antonozzi, I. Guanidinoacetate and creatine plus creatinine assessment in physiologic fluids: an effective diagnostic tool for the biochemical diagnosis of arginine:glycine amidinotransferase and guanidinoacetate methyltransferase deficiencies. Clin Chem 2002;48(10):1772-1778. View abstract.

The general strategy adopted by most present-day competitive bodybuilders is to make muscle gains for most of the year (known as the "off-season") and, approximately 12–14 weeks from competition, lose a maximum of body fat (referred to as "cutting") while preserving as much muscular mass as possible. The bulking phase entails remaining in a net positive energy balance (calorie surplus). The amount of a surplus in which a person remains is based on the person's goals, as a bigger surplus and longer bulking phase will create more fat tissue. The surplus of calories relative to one's energy balance will ensure that muscles remain in a state of anabolism.
Though weight training can stimulate the cardiovascular system, many exercise physiologists, based on their observation of maximal oxygen uptake, argue that aerobics training is a better cardiovascular stimulus. Central catheter monitoring during resistance training reveals increased cardiac output, suggesting that strength training shows potential for cardiovascular exercise. However, a 2007 meta-analysis found that, though aerobic training is an effective therapy for heart failure patients, combined aerobic and strength training is ineffective; "the favorable antiremodeling role of aerobic exercise was not confirmed when this mode of exercise was combined with strength training".[36]
Plyometrics exploit the stretch-shortening cycle of muscles to enhance the myotatic (stretch) reflex. This involves rapid alternation of lengthening and shortening of muscle fibers against resistance. The resistance involved is often a weighted object such as a medicine ball or sandbag, but can also be the body itself as in jumping exercises or the body with a weight vest that allows movement with resistance. Plyometrics is used to develop explosive speed, and focuses on maximal power instead of maximal strength by compressing the force of muscular contraction into as short a period as possible, and may be used to improve the effectiveness of a boxer's punch, or to increase the vertical jumping ability of a basketball player. Care must be taken when performing plyometric exercises because they inflict greater stress upon the involved joints and tendons than other forms of exercise.
Although creatine supplementation has been shown to be more effective on predominantly anaerobic intermittent exercise, there is some evidence of its positive effects on endurance activities. Branch [28] highlights that endurance activities lasting more than 150s rely on oxidative phosphorylation as primary energy system supplier. From this meta analysis [28], it would appear that the ergogenic potential for creatine supplementation on predominantly aerobic endurance exercise diminishes as the duration of the activity increases over 150s. However it is suggested that creatine supplementation may cause a change in substrate utilization during aerobic activity possibly leading to an increase in steady state endurance performance.

Beast Creature could be another good option for female athletes. It’s tasty, it contains five types of creatine, and it contains ingredients that could improve fat loss by increasing insulin sensitivity. One potential bonus is that it also has 70 percent of your daily biotin, a nutrient often included in women’s multivitamins due its purported benefits for hair and nails.
According to the abstract, in the stratified analyses by forms of aerobic exercise, weekly resistance exercise of 1 time or 1-59 minutes was associated with lower risks of total cardiovascular events and cardiovascular disease, regardless of meeting the aerobic exercise guidelines. The analysis showed that resistance training reduced the risk of cardiovascular events in 2 ways: training had a direct association with cardiovascular risk, and resistance training indirectly lowered cardiovascular risk by decreasing body mass index.
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]
The 1960s saw the gradual introduction of exercise machines into the still-rare strength training gyms of the time. Weight training became increasingly popular in the 1970s, following the release of the bodybuilding movie Pumping Iron, and the subsequent popularity of Arnold Schwarzenegger. Since the late 1990s increasing numbers of women have taken up weight training, influenced by programs like Body for Life; currently nearly one in five U.S. women engage in weight training on a regular basis.[4]
Adequate hydration is essential to muscle building, yet few people get enough water, even without daily exercise. So in addition to the daily 8 to 10 glasses of water recommended by the Dietary Guidelines for Americans, Karas suggests an additional 12 to 16 ounces before working out. He then recommends another 8 to 10 ounces for every 15 minutes of vigorous exercise.
Athletic performance. Creatine seems to help improve rowing performance, jumping height, and soccer performance in athletes. But the effect of creatine on sprinting, cycling, or swimming performance varies. The mixed results may relate to the small sizes of the studies, the differences in creatine doses, and differences in test used to measure performance. Creatine does not seem to improve serving ability in tennis players.
In a pilot study on youth with cystic fibrosis, supplementation of creatine at 12g for a week and 6g for eleven weeks afterward was associated with a time-dependent increase in maximal isometric strength reaching 14.3%, which was maintained after 12-24 weeks of supplement cessation (18.2% higher than baseline).[485] This study noted that more patients reported an increase in wellbeing (9 subjects, 50%) rather than a decrease (3, 17%) or nothing (6, 33%) and that there was no influence on chest or lung symptoms.[485]
McArdle’s disease is a myopathic disorder associated with fatigue and contractile dysfunction as a result of alterations in the release of glucose from glycogen (via defects in myophosphorylase enzyme function) resulting in an inability to conduct high intensity work as easily.[548] Creatine is thought to be therapeutic because beyond the general strength enhancing properties of creatine, people with McArdle’s disease have an upregulation of phosphofructokinase (PFK) enzyme activity [570] and increasing phosphocreatine storages suppresses the activity of this enzyme.[571]
That said, many people experience stomach cramps when they consume creatine monohydrate and it’s possible that taking a creatine with a different pH — usually creatine hydrochloride — can have a different effect on stomach acid and make for a creatine that digests more easily. As far as we know, the easier digestion doesn’t necessarily mean it’s more effective or that you need less of it to achieve the desired result.

Stronger muscles improve performance in a variety of sports. Sport-specific training routines are used by many competitors. These often specify that the speed of muscle contraction during weight training should be the same as that of the particular sport. Sport-specific training routines also often include variations to both free weight and machine movements that may not be common for traditional weightlifting.


If you have been struggling in the gym, getting over a plateau can seem very daunting. You are training hard, eating healthy, yet the results still aren’t coming. Creatine is a supplement which will help you gain strength, build muscle, lose fat, and give the energy you need to attack your workouts with an intensity that are guaranteed to give you results!
Carducci, C., Birarelli, M., Leuzzi, V., Carducci, C., Battini, R., Cioni, G., and Antonozzi, I. Guanidinoacetate and creatine plus creatinine assessment in physiologic fluids: an effective diagnostic tool for the biochemical diagnosis of arginine:glycine amidinotransferase and guanidinoacetate methyltransferase deficiencies. Clin Chem 2002;48(10):1772-1778. View abstract.
Whey, the liquid remaining after milk has been curdled and strained, is rapidly digested and absorbed and has a remarkable ability to stimulate muscle protein synthesis (Hayes & Cribb, 2008). Whey is available in three varieties — whey protein powder, whey protein concentrate, whey protein isolate — and all provide high levels of the essential and branched chain amino acids, vitamins and minerals.
In elite swimmers, the growth hormone response to sprints appears to be attenuated (39%) following creatine loading, although after a 3g maintenance phase (22-27 weeks), this attenuation was reduced to less than 5%.[404] Elsewhere in swimmers, resting growth hormone was unaffected by the loading phase,[397] suggesting that this is an exercise-exclusive effect.
The 1960s saw the gradual introduction of exercise machines into the still-rare strength training gyms of the time. Weight training became increasingly popular in the 1970s, following the release of the bodybuilding movie Pumping Iron, and the subsequent popularity of Arnold Schwarzenegger. Since the late 1990s increasing numbers of women have taken up weight training, influenced by programs like Body for Life; currently nearly one in five U.S. women engage in weight training on a regular basis.[4]
Does magnesium relieve migraines? Many people use magnesium, which is a naturally occurring mineral, to treat and prevent migraine headaches, especially those with aura. In this article, learn about the effectiveness of magnesium and discover whether there are any side effects or risks. We also list some of the foods that contain magnesium. Read now
Studies measuring extracellular water versus intracellular water note similar increases in both, associated with creatine. Creatine does not tend to disturb the ratios of water to dry mass in various tissues measured.[609] At least one study in older men (48-72 years) has failed to find a significant difference in both intracellular and extracellular water concentration after 14 weeks of 5g creatine daily (with gatorade) relative to gatorade in isolation, with the ratio being maintained.[615]
Several review studies assessing the safety of creatine supplementation tend to make note of increases in formaldehyde and possible carcinogenic results.[451][452] Specifically, creatine is metabolized into an intermediate called methylamine, which can be converted to formaldehyde by the SSAO enzyme.[453] An increase in urinary formaldehyde has been noted in youth given 21g of creatine for one week, during which both methylamine (820% increase) and formaldehyde (350%) were increased, relative to control.[454] However, a more prolonged study using 300mg/kg (loading dose of around 20g) in adults for ten weeks failed to replicate these effects.[455]
Several review studies assessing the safety of creatine supplementation tend to make note of increases in formaldehyde and possible carcinogenic results.[451][452] Specifically, creatine is metabolized into an intermediate called methylamine, which can be converted to formaldehyde by the SSAO enzyme.[453] An increase in urinary formaldehyde has been noted in youth given 21g of creatine for one week, during which both methylamine (820% increase) and formaldehyde (350%) were increased, relative to control.[454] However, a more prolonged study using 300mg/kg (loading dose of around 20g) in adults for ten weeks failed to replicate these effects.[455]
Creatine ethyl ester is more a pronutrient for creatinine rather than creatine,[74] and was originally created in an attempt to bypass the creatine transporter. It is currently being studied for its potential as a treatment for situations in which there is a lack of creatine transporters (alongside cyclocreatine as another possible example).[77] Its efficacy may rely on intravenous administration, however.
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