ציטוט:
dietary creatine supplementation does not affect some haematological indices, or indices of muscle damage and hepatic and renal function
tristan m robinson, dean a sewell, anna casey, gery steenge and paul l greenhaff
school of biomedical sciences, university of nottingham medical school, queen's medical centre, nottingham ng7 2uh, united kingdom
correspondence to:
Correspondence to: Dr p greenhaff email: paul.greenhaff@nottingham.ac.uk
background—the use of creatine (cr) as a nutritional supplement to aid athletic performance has gained widespread popularity among athletes. However, concerns have recently been expressed over potentially harmful effects of short and long term cr supplementation on health.
Methods—forty eight young healthy subjects were randomly allocated to three experimental protocols aimed at elucidating any potential health risks associated with five days (20 g/day) to nine weeks (3 g/day) of cr supplementation. Venous blood samples were collected before and after periods of cr supplementation and were analysed for some haematological indices, and for indices of hepatic, muscular, and renal dysfunction.
Findings—all measured indices were well within their respective normal range at all times. Serum creatinine concentration tended to be increased the day after cr supplementation. However, values had returned to baseline six weeks after the cessation of supplementation. These increases were probably attributable to increased creatinine production rather than renal dysfunction. No indication of impairment to the haematological indices measured, hepatic function, or muscle damage was apparent after cr supplementation.
Interpretation—these data provide evidence that there are no obvious adverse effects of acute or more chronic cr supplementation on the haematological indices measured, nor on hepatic, muscle, and renal function. therefore there is no apparent health risk associated with cr supplementation to healthy people when it is ingested in quantities that have been scientifically proven to increase muscle cr stores.
British journal of sports medicine 2000;34:284-288; doi:10.1136/bjsm.34.4.284
copyright © 2000 bmj publishing group ltd & british association of sport and exercise medicine.
Br j sports med 2000; 34:284-288
© 2000 the british journal of sports medicine
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ציטוט:
abstract creatine has been reported to be an effective ergogenic aid for athletes. However, concerns have been raised regarding the long-term safety of creatine supplementation. This study examined the effects of long-term creatine supplementation on a 69-item panel of serum, whole blood, and urinary markers of clinical health status in athletes. Over a 21-month period, 98 division ia college football players were administered in an open label manner creatine or non-creatine containing supplements following training sessions. Subjects who ingested creatine were administered 15.75 g/day of creatine monohydrate for 5 days and an average of 5 g/day thereafter in 5–10 g/day doses. Fasting blood and 24-h urine samples were collected at 0, 1, 1.5, 4, 6, 10, 12, 17, and 21 months of training. A comprehensive quantitative clinical chemistry panel was determined on serum and whole blood samples (metabolic markers, muscle and liver enzymes, electrolytes, lipid profiles, hematological markers, and lymphocytes). In addition, urine samples were quantitatively and qualitative analyzed to assess clinical status and renal function. At the end of the study, subjects were categorized into groups that did not take creatine (n = 44) and subjects who took creatine for 0–6 months (mean 4.4 ± 1.8 months, n = 12), 7–12 months (mean 9.3 ± 2.0 months, n = 25), and 12–21 months (mean 19.3 ± 2.4 months, n = 17). Baseline and the subjects' final blood and urine samples were analyzed by manova and 2 × 2 repeated measures anova univariate tests. Manova revealed no significant differences (p = 0.51) among groups in the 54-item panel of quantitative blood and urine markers assessed. Univariate analysis revealed no clinically significant interactions among groups in markers of clinical status. In addition, no apparent differences were observed among groups in the 15-item panel of qualitative urine markers. results indicate that long-term creatine supplementation (up to 21-months) does not appear to adversely effect markers of health status in athletes undergoing intense training in comparison to athletes who do not take creatine
1) exercise and sport nutrition laboratory, department of hmse, university of memphis, memphis, tn 38152-3480, usa
(2) exercise and sport nutrition laboratory, center for exercise, nutrition and preventive health research, department of health, human performance and recreation, baylor university, p.o. Box 97313, waco, tx 76798-7313, usa
(3) department of hpess, arkansas state university, p.o. Box 240, state university, ar 72467, usa
(4) the milnor clinic, 920 estate, suite 8, memphis, tn 38119, usa
(5) metaresponse sciences, inc., 30131 town center drive, #211, laguna niguel, ca 92677, usa
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בבקשה, והרופא שהלכת אליו הוא כנראה רופא ילדים וההשכלה שלו היא בהתאם לרפואת ילדים.. לא חשבת על זה? לא שאני מזלזל בזה אבל זה כמו שתביא למוסך של תלת אופן ג'יפ ותבקש שיתקנו לך את המנוע ויחליפו גלגלים |
