מחקר חדש ומעניין whey vs casein

[bigman]

מחקר חדש ומעניין whey vs casein

על פניו נראה מעניין אבל צריך לשים לב לגודל הקבוצה שנבדקה רק 13 מפתחי גוף. זה נראה מחקר שקשה להסיק ממנו מסקנות כיוון שלא יודעים מה ההשפעה של תזונה במהלך היום על אותם הפרמטרים שנבדקו. מעניין אם התזונה במחקר התבססה רק על אותם מקורות חלבון לאורך כל היום כי משורה אחת בתקציר אפשר להבין שכן וזה הופך אתהמחקר לעוד יותר מעניין!! In a double-blind protocol, 13 male, recreational bodybuilders supplemented their normal diet with either WI or C (1.5 gm/kg body wt/d) for the duration of the program. בכל מקרה חבל שאין לי את המאמר המלא אשמח אם מישהו יצליח לעלות אותו לפורום ..

 

[bigman]

סליחה..התקציר למאמר

Int J Sport Nutr Exerc Metab. 2006 Oct;16(5):494-509 The effect of whey isolate and resistance training on strength, body composition, and plasma glutamine Different dietary proteins affect whole body protein anabolism and accretion and therefore, have the potential to influence results obtained from resistance training. This study examined the effects of supplementation with two proteins, hydrolyzed whey isolate (WI) and casein (C), on strength, body composition, and plasma glutamine levels during a 10 wk, supervised resistance training program. In a double-blind protocol, 13 male, recreational bodybuilders supplemented their normal diet with either WI or C (1.5 gm/kg body wt/d) for the duration of the program. Strength was assessed by 1-RM in three exercises (barbell bench press, squat, and cable pull-down). Body composition was assessed by dual energy X-ray absorptiometry. Plasma glutamine levels were determined by the enzymatic method with spectrophotometric detection. All assessments occurred in the week before and the week following 10 wk of training. Plasma glutamine levels did not change in either supplement group following the intervention. The WI group achieved a significantly greater gain (P < 0.01) in lean mass than the C group (5.0 +/- 0.3 vs. 0.8 +/- 0.4 kg for WI and C, respectively) and a significant (P < 0.05) change in fat mass (-1.5 +/- 0.5 kg) compared to the C group (+0.2 +/- 0.3 kg). The WI group also achieved significantly greater (P < 0.05) improvements in strength compared to the C group in each assessment of strength. When the strength changes were expressed relative to body weight, the WI group still achieved significantly greater (P < 0.05) improvements in strength compared to the C group.

 

[Gal T]

זה דוגמא נפלאה למחקר מכור

אם תכנס למחקר המלא ותעיין בכל מיני פרטים על תהליך המחקר וקבוצות המחקר, אתה תראה פרמטרים שונים ששומטים את הבסיס שלו. הוא כנראה ממומן ע"י חברת תוספי מזון כלשהיא, בדיוק כמו זה; *** J Strength Cond Res. 2006 Aug;20(3):643-53. The effects of protein and amino acid supplementation on performance and training adaptations during ten weeks of resistance training. Center for Exercise, Nutrition and Preventive Health Research, Department of Health, Human Performance and Recreation, Baylor University, Waco, TX 76798, USA. The purpose of this study was to examine the effects of whey protein supplementation on body composition, muscular strength, muscular endurance, and anaerobic capacity during 10 weeks of resistance training. Thirty-six resistance-trained males (31.0 +/- 8.0 years, 179.1 +/- 8.0 cm, 84.0 +/- 12.9 kg, 17.8 +/- 6.6%) followed a 4 days-per-week split body part resistance training program for 10 weeks. Three groups of supplements were randomly assigned, prior to the beginning of the exercise program, in a double-blind manner to all subjects: 48 g per day (g.d(-1)) carbohydrate placebo (P), 40 g.d(-1) of whey protein + 8 g.d(-1) of casein (WC), or 40 g.d(-1) of whey protein + 3 g.d(-1) branched-chain amino acids + 5 g.d(-1) L-glutamine (WBG). At 0, 5, and 10 weeks, subjects were tested for fasting blood samples, body mass, body composition using dual-energy x-ray absorptiometry (DEXA), 1 repetition maximum (1RM) bench and leg press, 80% 1RM maximal repetitions to fatigue for bench press and leg press, and 30-second Wingate anaerobic capacity tests. No changes (p > 0.05) were noted in all groups for energy intake, training volume, blood parameters, and anaerobic capacity. WC experienced the greatest increases in DEXA lean mass (P = 0.0 +/- 0.9; WC = 1.9 +/- 0.6; WBG = -0.1 +/- 0.3 kg, p < 0.05) and DEXA fat-free mass (P = 0.1 +/- 1.0; WC = 1.8 +/- 0.6; WBG = -0.1 +/- 0.2 kg, p < 0.05). Significant increases in 1RM bench press and leg press were observed in all groups after 10 weeks. In this study, the combination of whey and casein protein promoted the greatest increases in fat-free mass after 10 weeks of heavy resistance training. Athletes, coaches, and nutritionists can use these findings to increase fat-free mass and to improve body composition during resistance training . PMID: 16937979 [PubMed - in process]

 

[tommythecat]

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