Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

No description available.

This study investigated social cognitive determinants of creatine supplementation among 171 male, undergraduate, recreational weight-lifters. Participants responded to a packet of questionnaires that assessed their history and rate of creatine use, self-efficacy for improving their workout performance with and without creatine, and expected outcomes of improved workout performance and creatine use, as well as several other demographic variables. Fifty percent of the sample reported past creatine use. The data was used to establish the internal consistency, test-retest reliability and predictive validity of factor-based scales for valued outcome expectancies and disincentives for creatine use scales. A social cognitive model was shown to predict past creatine use (R² = .372). The results lay the groundwork for further examination of the determinants of creatine supplementation and the use of other controversial and potentially harmful performance-enhancing dietary supplements. / Master of Science

Thesis (M.S.)--Springfield College, 2003. / Includes bibliographical references.

No description available.

Thesis (Ph. D.)--University of Missouri--Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 102-113).

No description available.

Athletes who participate in sports where performance relies on repeated high-intensity efforts could benefit from creatine (Cr) ingestion due to an increased ability to perform and recover from high-intensity exercise bouts either during training or competition. However, few studies exist which have investigated the effects of acute short-term Cr supplementation on appropriately simulated soccer-specific performance.Aims. To determine the reproducibility of a 90 minute soccer-specific performance test and to subsequently examine the effects of acute short-term Cr ingestion (1 week) on soccer-specific physical performance. Study design. Two experimental designs were adopted for this thesis. For study one, a test-retest design was used to determine the reliability and validity of the Ball-sport Endurance And Sprint Test (BEAST). Two trials of the BEAST were performed, separated by five to seven days. For study two, a randomised, triple-blind, placebo-controlled experimental design was adopted to determine the efficacy of acute short-term Cr supplementation (seven days) on soccer-specific performance, using the BEAST protocol.Methods. Twenty male amateur soccer players volunteered to participate in the study. For study one, the test-retest reliability of several soccer-specific performance measures obtained during a modified version of the BEAST was quantified using the standard error of measurement (Van Cutsem, Duchateau, & Hainaut) (or typical error) (Hopkins, 2000), coefficient of variation (CV), and Intraclass Correlation Coefficient (ICC). For study two, the cohort was split and subjects randomly allocated to one of two groups (Cr supplementation and Placebo) on a matched-pair basis. The Cr group (mean age 25.4 ± 4.5 years, mean body-mass 79.3 ± 10.5 kg) ingested 20 g of Cr and 8 g of glucose powder per day for seven days, whereas the placebo (mean age 26.7 ± 4.6 years, mean body-mass 80.8 ± 8.6 kg) group ingested 20 g of corn-flour and 8 g of glucose per day for seven days. The effects of acute short-term Cr supplementation were analysed by repeated measures ANOVA. In addition, effect sizes (ES) were calculated and entered with the associated p-value into Hopkins' spreadsheet for determination of the ES confidence limits (95%) and the chances that the true effect was substantial (i.e. ES ≥ 0.2). Clinical/practical inferences were made accordingly.Results. Study 1: The BEAST protocol had good reliability (high ICC values, relatively low coefficients of variation, low noise to signal ratios) and face validity (HR, VO2, distances covered, duration, and movements performed in the BEAST were all similar to those reported in actual soccer matches). Study 2: Performance of the four major physical measures (12 m sprint, 20 m sprint, circuit time and vertical jump) during the BEAST deteriorated during the second half relative to the first half for both Cr and placebo groups, indicating a fatigue effect associated with the protocol. HR and body-mass values also decreased for both groups during the 90 minute protocol. However, there was no statistically significant differences between the groups for these four measures or for body-mass, HR or VO2max values, suggesting Cr had no substantial effect (relative to placebo) on improving physical performance (or reducing fatigue). When the effects were assessed for the whole 90 minute BEAST protocol, all effects showed a negative trend and, correspondingly, the chances of a detrimental effect were greater than the chances of a beneficial effect.Conclusions: The 90 minute BEAST protocol had good reliability and face validity making it a suitable soccer simulation and performance protocol with which to investigate the effects of Cr supplementation on soccer performance. However, no significant (statistical or clinical) effects of acute short-term Cr supplementation on soccer performance were observed suggesting its potential use as an ergogenic aid for soccer players is questionable.

Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: Cheng-Shun (Richard) Fang, Dept. of Health, Nutrition, and Exercise Sciences. Includes bibliographical references.

Early research with beta-alanine (beta-ALA) supplementation has shown increases in muscle carnosine as well as improvements in body composition, exercise performance and blood lactate levels. Creatine monohydrate supplementation has been extensively researched for its effects on anaerobic exercise performance. Recently, a new line of studies have examined the combined effects beta-ALA and creatine supplementation on anaerobic exercise performance and lactate threshold. The purpose of the present study is to examine the acute and chronic effects of beta-ALA supplementation with and without creatine monohydrate on body composition, aerobic and anaerobic exercise performance, and muscle carnosine and phosphagen levels in college-aged recreationally active females. Thirty-two females were randomized in a double-blind placebo controlled manner into one of four supplementation groups including beta-ALA only, creatine only, beta-ALA and creatine combined and placebo. Participants supplemented for four weeks and reported for testing at baseline, day 7 and day 28. Testing sessions consisted of a resting muscle biopsy of the vastus lateralis, body composition measurements, a graded exercise test on the cycle ergometer for VO2max and lactate threshold, and multiple Wingate tests for anaerobic exercise performance. Results showed all supplementation strategies increasing muscle carnosine levels over placebo after four weeks, but not between groups. Muscle creatine increased for all groups after four weeks, but not between groups. There were improvements for all groups with body composition after four weeks, despite the present study not including a specific training protocol. There were no group differences observed for aerobic exercise, blood lactate levels, lactate threshold, ventilatory threshold, peak power, mean power, total work or rate of fatigue. There were some trends for anaerobic exercise indicating groups supplementing with creatine may have greater improvements, however, these findings were not statistically significant. The present study failed to show any additive effects of beta-ALA and creatine supplementation for body composition, aerobic exercise, lactate threshold or anaerobic exercise measures. This could be due to the small sample size resulting in low power and effect sizes. Previous research has demonstrated that four weeks of beta-ALA and creatine supplementation was enough time to increase muscle carnosine and phosphagen levels. However, perhaps more time is needed for performance adaptations to occur, especially without the addition of an exercise training component.