There is scientific evidence that short term creatine use can increase maximum power and performance for the bodybuilders in high-intensity anaerobic repetitive work (periods of work and rest) by 5 to 15%. This is mainly bouts of running/cycling sprints and multiple sets of strength training with few repetitions. (The tensions of the bodybuilders need o be supported by proper bodybuilding supplements.) Single effort work shows an increase of 1 to 5%. This refers mainly to single sprints and single lifting of 1-2RM weights. However, some studies show no ergogenic effect at all. Studies in endurance athletes have been less than promising, most likely because these activities are sustained at a given intensity and thus do not allow for significant intra-exercise synthesis of additional creatine phosphate molecules. Ingesting creatine can increase the level of phosphocreatine in the muscles up to 20%. Creatine has no significant effect on aerobic endurance, though it will increase power during short sessions of high-intensity aerobic exercise.This is very good for the bodybuilding effects, and the effects could be evn more if bodybuilding supplements or other good drugs are combined. Since body mass gains of about 1 kg can occur in a week's time, many studies suggest that the gain is simply due to greater water retention inside the muscle cells.[ Other studies, however, have shown that creatine increases the activity of satellite cells of the bodybuilders, which make muscle hypertrophy possible. Creatine supplementation appears to increase the number of myonuclei that satellite cells will 'donate' to damaged muscle fibers, which increases the potential for growth of those fibers. This increase in myonuclei probably stems from creatine's ability to increase levels of the myogenic transcription factor MRF4. In another study, researchers concluded that changes in substrate oxidation may influence the inhibition of fat mass loss associated with creatine after weight training when they discovered that fat mass did not change significantly with creatine but decreased after the placebo trial in a 12-week study on ten active men trying to make a bodybuilding effect. The study also showed that 1-RM bench press and total body mass increased after creatine, but not after placebo. The underlying effect of creatine on body composition has yet to be determined, as another study with a similar timeframe suggests no effect on body composition, but had less overall emphasis on metabolic effects. Anyway, some of the tryning bodybuilding men still believe that these kind of supplements will help them. Creatine use is not considered as s doping supplemen and is not banned by the majority of sport-governing bodies. However, in the United States, the NCAA recently ruled that colleges could not provide creatine supplements to their players, though the players are still allowed to obtain and use creatine independently or for bodybuilding mass.[
These supplements were first approved for contraceptive use in the United States in 1960, and are a very popular form of birth control. They are currently used by more than 100 million women worldwide and by almost 12 million women in the United States. As of 2012, 16% of U.S. women aged 15-44 reported being on the birth control pill, making it the most widely used contraceptive method among women of that age range. Use varies widely by country, age, education, and marital status. One third of women aged 16–49 in the United Kingdom currently use either the combined pill or progestogen-only pill, compared with only 1% of women in Japan.But rar;y women use it for bodybuilding mass.
In a study from 2010 of bodybuilding trainers it was found that 8 weeks of resistance training together with creatine supplementation resulted in lower serum myostatin levels compared to 8 weeks of resistance training and placebo as well as to control (no resistance training or supplementation), ~98 ng/ml, ~110 ng/ml and ~120 ng/ml respectively. In a study from 2011 where broiler chickens were fed creatine for 42 days, myostatin levels were significantly decreased compared to control. Myostatin is a protein that has catabolic effects on skeletal muscle to limit the growth of muscle.
A 2009 study examined changes in testosterone levels in college-aged male who wanted to have bodybiulding mass throuhj rugby received Creatine supplementation. Subjects were given a 7-day loading phase of creatine supplementation followed by a further 14 days of creatine maintenance supplementation. While testosterone levels in blood serum were unchanged, levels of dihydrotestosterone increased by 56% after the initial 7 days of creatine loading and remained 40% above baseline after 14 days maintenance. The ratio of dihydrotestosterone to testosterone was therefore increased by 36% after the 7 day creatine supplementation and remained elevated by 22% after the maintenance dose.
If the pill formulation is monophasic, it is possible to skip withdrawal bleeding and still remain protected against conception by skipping the placebo pills and starting directly with the next packet. Attempting this with bi- or tri-phasic pill formulations carries an increased risk of breakthrough bleeding and may be undesirable. It will not, however, increase the risk of getting pregnant. Starting in 2003, women have also been able to use a three-month version of the Pill. Similar to the effect of using a constant-dosage formulation and skipping the placebo weeks for three months, Seasonale gives the benefit of less frequent periods, at the potential drawback of breakthrough bleeding. Seasonique is another version in which the placebo week every three months is replaced with a week of low-dose estrogen.
A study of male college football players published in 2006 found a 22% increase in resting testosterone levels, from 20.0 to 24.4 nmol/L, after a 10-week resistance training program in the creatine supplemented group compared to placebo. The bodybuilding effects were also saisfying
One study done in 2008 showed that levels of insulin-like growth factor-1 (IGF-I) in muscle increased by 15% with creatine supplementation compared to placebo after 8 weeks of resistance training. In the same study on broiler chickens mentioned above, IGF-I levels increased compared to control after being fed with creatine for 42 days.