The use of creative monohydrate (CM) supplementation by athletes to increase strength and lean body mass has great anecdotal support. Therefore, the purpose of this investigation was to document the chronic effects of CM supplementation on resistance trained athletes. Sixteen collegiate football players were randomly separated into a CM and placebo (P) group. Supplementation in capsule form consisted of 5 g CM or P per day throughout a 10 week resistance training program. Pre- and Post-testing consisted of 1) Weight. 2) Body fat estimation. 3) One repetition maximal bench press, squat, and power clean. 4) Cybex testing was also included. Results revealed the CM group was able to significantly increase measures of strength and power, as well as increase body mass without a change in body fat %, while the P group showed no significant changes. Data was analyzed using a paired t-test and ANCOVA (p < 0.05). CM PPrePostPrePostBody Wt (lbs)234.5 + 34.41237.37 + 31.34*215.57 ± 55.12213.0 ± 48.897-site fat %15.37+5.5116.68+6.5813.52 + 10.0913.58+8.33Bench Press (lbs)328.75 + 27.87- 340.0 + 27.65*287.14 + 58.94283.57 + 48.71Squats (lbs)532.86 + 130.92592.14 + 123.86*489.17 + 149.81512.50 ± 161.89Power Cleans271.88 + 47.73288.75 + 45.34*246.00 + 33.99241.00 + 64.65* Denotes significant measureThe data from this study supports the anecdotal claims. Further, contrary to what would be expected with long term resistance training alone, the placebo group failed to increase strength and power measures. This suggests that the resistance program lacked sufficient stimuli or that overtraining might have occurred. However, subjects ingesting CM were able to increase strength and power measures. Thus, it appears that CM may also serve as a buffer to overtraining. / School of Physical Education

Thesis (MPhil (Physiological Sciences))--University of Stellenbosch, 2006. / Background. Creatine monohydrate is widely used for its purported ergogenic and anabolic properties. The mechanism by which creatine supplementation enhances muscle growth is not understood. This study was undertaken to determine whether creatine monohydrate supplementation increases the conversion rate of testosterone to dihydrotestosterone. An increase in dihydrotestosterone could partly explain the beneficial effect of creatine monohydrate on muscle hypertrophy. Methods. Subcommittee C of the research committee of the University of Stellenbosch approved the study. Project number 2001/ C045. The study was designed as a double blind crossover with subjects (n = 20) in each leg of the study. Group 1 (n = 10) taking creatine monohydrate and group 2 (n = 10) glucose during the first leg of the study. In accordance with crossover study design the groups were reversed in the second leg of the study. Gelatin capsules were filled with 5g of either creatine monohydrate or 5g of glucose. Subjects taking creatine monohydrate also took 25g of glucose to improve absorption of creatine. Subjects took creatine monohydrate 25g plus 25g of glucose (ten capsules in all) or glucose ten capsules per day for seven days in the loading phase. In the maintenance phase they took 5g of creatine monohydrate plus 25g of glucose (six capsules in all) per day or six capsules of glucose, for 14 days. The groups were reversed after a six-week washout period and the dosages repeated as per crossover study design. Blood samples were taken on day zero of the study as baseline measurements, repeated on day 7, (after the loading phase), and again on day 21, (after the maintenance phase). These were again repeated in the second leg of the study as per crossover design. Serum was separated within one hour of collection and stored at minus 70 oC. Testosterone and dihydrotestosterone concentrations were determined using a radio-immunoassay kit by an accredited university laboratory. The percentage conversion of testosterone to dihydrotestosterone was calculated. The results were statistically analyzed: A paired t - tests at the beginning of each leg of the study and repeated measure analysis of variance, for the pooled data for each condition over the whole study. Results. The difference in blood levels of testosterone and dihydrotestosterone on both days 0, were not statistically significant. This made the pooling of the data possible. The difference in the percentage conversion of testosterone to dihydrotestosterone over the study period between the creatine monohydrate condition and the glucose condition, was however significant (p < 0.0001). In this small study highly significant statistical results were obtained. The answer to how creatine taken as a supplement exerts its effect may lie in the increased rate of conversion of testosterone to dihydrotestosterone. Conclusion. With the known greater androgenic effect of dihydrotestosterone as opposed to testosterone, the increase in testosterone conversion to dihydrotestosterone could explain how creatine supplementation exerts its anabolic effect in susceptible individuals. A larger study should be done to confirm these results and answer the questions arising from the findings.

Effects of pre-slaughter sheep handling and animal-related factors on Creatine Kinase levels and physico-chemical attributes of mutton By Chulayo Amanda Yucca The objective of the study was to determine the effects of pre-slaughter sheep handling and animal-related factors on Creatine kinase (CK) levels and physico-chemical characteristics of mutton from South African sheep breeds. One hundred and seventy-three castrated male sheep from four breeds (15 Dormer, 46 South African Mutton Merino, 77 Dorper and 35 Blackhead Persian) were used. The animals were grouped according to age categories. The grouping was as follows: Group 1 (6 ≤ 8 months), Group 2 (9 ≤ 12 months) and Group 3 (13 ≤ 16 months). Blood samples for CK determination were collected at exanguination using disposable vacutainer tubes. Representative samples of the Muscularis longissimuss thoracis et. lumborum (LTL) muscle were taken for the determination of ultimate pH (pHu), colour (L*-lightness, b*- redness and a*- yellowness), thawing and cooking losses and meat tenderness. Significant (P<0.01) breed effects were observed on CK levels with Dormer having the highest CK values. Significant linear relationships were observed between pre-slaughter condition and CK levels. There were positive correlations between colour coordinates L* and b* (r =+0.22) and between a* and b* (r =+0.63). Cooking loss and Warner Braztler Shear Force (WBSF) values were positively correlated (r =+0.29). The Principal Component Analysis (PCA) showed a significant variance for CK and between physico-chemical characteristics of mutton. There were no relationships between CK levels and physico-chemical characteristics of mutton. Significant breed and age effects on pHu, L, a*, b*, thaw %, CL and WBSF of mutton were observed. iv It was concluded that, pre-slaughter conditions affect CK levels and physico-chemical characteristics of mutton. However, there were no relationships between CK levels and physico-chemical characteristics of mutton.