Effects of creatine loading on electromyographic fatigue threshold during cycle ergometry in college-aged women

This is the publisher's version, also found at http://www.jissn.com/content/4/1/20The purpose of this study was to examine the effects of 5 days of Creatine (Cr) loading on the electromyographic fatigue threshold (EMGFT) in college-aged women. Fifteen healthy college-aged women (mean ± SD = 22.3 ± 1.7 yrs) volunteered to participate in this double-blind, placebocontrolled study and were randomly placed into either placebo (PL – 10 g of flavored dextrose powder; n = 8) or creatine (Cr – 5 g di-creatine citrate plus 10 g of flavored dextrose powder; n = 7; Creatine Edge, FSI Nutrition) loading groups. Each group ingested one packet 4 times per day (total of 20 g/day) for 5 days. Prior to and following supplementation, each subject performed a discontinuous incremental cycle ergometer test to determine their EMGFT value, using bipolar surface electrodes placed on the longitudinal axis of the right vastus lateralis. Subjects completed a total of four, 60 second work bouts (ranging from 100–350 W). The EMG amplitude was averaged over 10 second intervals and plotted over the 60 second work bout. The resulting slopes from each successive work bouts were used to calculate EMGFT. A two-way ANOVA (group [Cr vs. PL] × time [pre vs. post]) resulted in a significant (p = 0.031) interaction. Furthermore, a dependent samples t-test showed a 14.5% ± 3.5% increase in EMGFT from pre- to post-supplementation with Cr (p = 0.009), but no change for the PL treatment (-2.2 ± 5.8%; p = 0.732). In addition, a significant increase (1.0 ± 0.34 kg; p = 0.049) in weight (kg) was observed in the Cr group but no change for PL (-0.2 kg ± 0.2 kg). These findings suggest that 5 days of Cr loading in women may be an effective strategy for delaying the onset of neuromuscular fatigue during cycle ergometry

Minimal nutrition intervention with high-protein/low-carbohydrate and low-fat, nutrient-dense food supplement improves body composition and exercise benefits in overweight adults: A randomized controlled trial

Background: Exercise and high-protein/reduced-carbohydrate and -fat diets have each been shown separately, or in combination with an energy-restricted diet to improve body composition and health in sedentary, overweight (BMI > 25) adults. The current study, instead, examined the physiological response to 10 weeks of combined aerobic and resistance exercise (EX) versus exercise + minimal nutrition intervention designed to alter the macronutrient profile, in the absence of energy restriction, using a commercially available high-protein/low-carbohydrate and low-fat, nutrient-dense food supplement (EXFS); versus control (CON). Methods: Thirty-eight previously sedentary, overweight subjects (female = 19; male = 19) were randomly assigned to either CON (n = 10), EX (n = 14) or EXFS (n = 14). EX and EXFS participated in supervised resistance and endurance training (2× and 3×/wk, respectively); EXFS consumed 1 shake/d (weeks 1 and 2) and 2 shakes/d (weeks 3–10). Results: EXFS significantly decreased total energy, carbohydrate and fat intake (-14.4%, -27.2% and -26.7%, respectively; p < 0.017), and increased protein and fiber intake (+52.1% and +21.2%, respectively; p < 0.017). EX and EXFS significantly decreased fat mass (-4.6% and -9.3%, respectively; p < 0.017), with a greater (p < 0.05) decrease in EXFS than EX and CON. Muscle mass increase only reached significance in EXFS (+2.3%; p < 0.017), which was greater (p < 0.05) than CON but not EX (+1.1%). Relative VO2max improved in both exercise groups (EX = +5.0% and EXFS = +7.9%; p < 0.017); however, only EXFS significantly improved absolute VO2max (+6.2%; p = 0.001). Time-to-exhaustion during treadmill testing increased in EX (+9.8%) but was significantly less (p < 0.05) than in EXFS (+21.2%). Total cholesterol and LDL decreased only in the EXFS (-12.0% and -13.3%, respectively; p < 0.017). Total cholesterol-to-HDL ratio, however, decreased significantly (p < 0.017) in both exercise groups. Conclusion: Absent energy restriction or other dietary controls, provision of a high-protein/low-carbohydrate and -fat, nutrient-dense food supplement significantly, 1) modified ad libitum macronutrient and energy intake (behavior effect), 2) improved physiological adaptations to exercise (metabolic advantage), and 3) reduced the variability of individual responses for fat mass, muscle mass and time-to-exhaustion – all three variables improving in 100% of EXFS subjects

Total body water estimations in healthy men and women using bioimpedance spectroscopy: a deuterium oxide comparison

<p>Abstract</p> <p>Background</p> <p>Total body water (TBW) estimations have been used to estimate body composition, particularly fat-free mass, to aid in nutritional interventions, and to monitor hydration status. In the past, bioimpedance spectroscopy (BIS) devices have been used to estimate TBW. Previous investigations have examined the validity of the XiTRON 4000B (XiTRON Technologies) BIS device for estimating TBW. Recently, a new BIS device (Imp™ SFB7) has become available, claiming greater precision when estimating TBW. The Imp™ SFB7 (SFB7) is based on similar BIS principles, while offering increased portability and a greater range of frequencies when compared to older devices, such as the XiTRON 4000B (4000B). The purpose of this study was to examine the validity of the SFB7 for estimating total body water in healthy college-age men and women compared to the 4000B and deuterium oxide (D₂O).</p> <p>Methods</p> <p>Twenty-eight Caucasian men and women (14 men, 14 women; 24 ± 4 yrs; 174.6 ± 8.7 cm; 72.80 ± 17.58 kg) had their TBW estimated by the SFB7, the 4000B, and D₂O.</p> <p>Results</p> <p>Both BIS devices produced similar standard error of estimate (<it>SEE</it>) and <it>r </it>values (SFB7, <it>SEE </it>= 2.12L, <it>r </it>= 0.98; 4000B, <it>SEE </it>= 2.99L, <it>r </it>= 0.96) when compared to D₂O, though a significant constant error (<it>CE</it>) was detected for the 4000B (2.26L, <it>p </it>≤ 0.025). The 4000B produced a larger total error (<it>TE</it>) and <it>CE </it>(<it>TE </it>= 3.81L, <it>CE </it>= 2.26L) when compared to the SFB7 (<it>TE </it>= 2.21L, <it>CE </it>= -0.09L). Additionally, the limits of agreement were larger for the 4000B (-3.88 to 8.39L) than the SFB7 (-4.50 to 4.31L). These results were consistent when sex was analyzed separately, though women produced lower <it>SEE </it>and <it>TE </it>values for both devices.</p> <p>Conclusion</p> <p>The 4000B and SFB7 are valid BIS devices when compared to D₂O to estimate TBW in college-age Caucasian men and women. Furthermore, the new SFB7 device displayed greater precision in comparison to the 4000B, which may decrease the error when estimating TBW on an individual basis.</p

Beta-alanine supplementation and high-intensity interval training augments metabolic adaptations and endurance performance in college-aged men

A randomized, double-blind, placebo-controlled study was conducted to evaluate the effects β-alanine supplementation and high-intensity interval training (HIIT) on endurance performance

Pre-workout consumption of Celsius® enhances the benefits of chronic exercise on body composition and cardiorespiratory fitness

The functional beverage Celsius®, has recently been shown, after acute and chronic (28 days) consumption, to increase resting metabolism and serum blood markers of lipolysis in healthy, college-aged men and women. The purpose of this study was to examine the combined effects of a 10-week exercise program while consuming Celsius® on body composition and cardiorespiratory fitness changes in sedentary men and women

The Ethical Triage and Management Guidelines of the Entrapped and Mangled Extremity in Resource Scarce Environments: A Systematic Literature Review.

ABSTRACTObjective:A systematic literature review (SLR) was performed to elucidate the current triage and treatment of an entrapped or mangled extremity in resource scarce environments (RSEs).Methods:A lead researcher followed the search strategy following inclusion and exclusion criteria. A first reviewer (FR) was randomly assigned sources. One of the 2 lead researchers was the second reviewer (SR). Each determined the level of evidence (LOE) and quality of evidence (QE) from each source. Any differing opinions between the FR and SR were discussed between them, and if differing opinions remained, then a third reviewer (the other lead researcher) discussed the article until a consensus was reached. The final opinion of each article was entered for analysis.Results:Fifty-eight (58) articles were entered into the final study. There was 1 study determined to be LOE 1, 29 LOE 2, and 28 LOE 3, with 15 determined to achieve QE 1, 37 QE 2, and 6 QE 3.Conclusion:This SLR showed that there is a lack of studies producing strong evidence to support the triage and treatment of the mangled extremity in RSE. Therefore, a Delphi process is suggested to adapt and modify current civilian and military triage and treatment guidelines to the RSE

Effects of β-alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind trial

Background: Intermittent bouts of high-intensity exercise result in diminished stores of energy substrates, followed by an accumulation of metabolites, promoting chronic physiological adaptations. In addition, β-alanine has been accepted has an effective physiological hydrogen ion (H+) buffer. Concurrent high-intensity interval training (HIIT) and β-alanine supplementation may result in greater adaptations than HIIT alone. The purpose of the current study was to evaluate the effects of combining β-alanine supplementation with high-intensity interval training (HIIT) on endurance performance and aerobic metabolism in recreationally active college-aged men. Methods: Forty-six men (Age: 22.2 ± 2.7 yrs; Ht: 178.1 ± 7.4 cm; Wt: 78.7 ± 11.9; VO2peak: 3.3 ± 0.59 l·min-1) were assessed for peak O2 utilization (VO2peak), time to fatigue (VO2TTE), ventilatory threshold (VT), and total work done at 110% of pre-training VO2peak (TWD). In a double-blind fashion, all subjects were randomly assigned into one either a placebo (PL – 16.5 g dextrose powder per packet; n = 18) or β-alanine (BA – 1.5 g β-alanine plus 15 g dextrose powder per packet; n = 18) group. All subjects supplemented four times per day (total of 6 g/day) for the first 21-days, followed by two times per day (3 g/day) for the subsequent 21 days, and engaged in a total of six weeks of HIIT training consisting of 5–6 bouts of a 2:1 minute cycling work to rest ratio. Results: Significant improvements in VO2peak, VO2TTE, and TWD after three weeks of training were displayed (p \u3c 0.05). Increases in VO2peak, VO2TTE, TWD and lean body mass were only significant for the BA group after the second three weeks of training. Conclusion: The use of HIIT to induce significant aerobic improvements is effective and efficient. Chronic BA supplementation may further enhance HIIT, improving endurance performance and lean body mass

Research and Education in Computational Science and Engineering

Over the past two decades the field of computational science and engineering (CSE) has penetrated both basic and applied research in academia, industry, and laboratories to advance discovery, optimize systems, support decision-makers, and educate the scientific and engineering workforce. Informed by centuries of theory and experiment, CSE performs computational experiments to answer questions that neither theory nor experiment alone is equipped to answer. CSE provides scientists and engineers of all persuasions with algorithmic inventions and software systems that transcend disciplines and scales. Carried on a wave of digital technology, CSE brings the power of parallelism to bear on troves of data. Mathematics-based advanced computing has become a prevalent means of discovery and innovation in essentially all areas of science, engineering, technology, and society; and the CSE community is at the core of this transformation. However, a combination of disruptive developments---including the architectural complexity of extreme-scale computing, the data revolution that engulfs the planet, and the specialization required to follow the applications to new frontiers---is redefining the scope and reach of the CSE endeavor. This report describes the rapid expansion of CSE and the challenges to sustaining its bold advances. The report also presents strategies and directions for CSE research and education for the next decade.Comment: Major revision, to appear in SIAM Revie