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Abstract: Preexercise nutritional investigations have recently become a popular avenue of examining the interaction of multiple ingredients on exercise and training methods. The critical velocity (CV) test is used to quantify the relationship between total running distance and time to exhaustion (TTE), yielding aerobic (CV) and anaerobic parameters (anaerobic running capacity [ARC]). The purpose of this study was to examine the hypothesis that a preexercise supplement containing caffeine, creatine, and amino acids (Game Time; Corr-Jen Laboratories Inc, Aurora, CO) would positively impact CV and ARC in college-aged men and women. In a single-blind crossover design, 10 participants consumed the preexercise supplement (ACT) or placebo (PL) before each testing session. Each participant completed runs to exhaustion on a treadmill at 110%, 90% (day 1), and 105% and 100% (day 2) of the peak velocity (PV) determined from a graded exercise test. The ACT elicited a 10.8% higher ARC (P = .02) compared with the PL, whereas no difference was found in CV (0.6%, P = .38). The TTE was greater for the ACT than the PL at 110% (ACT = 125.7 ± 9.6 seconds, PL = 117.3 ± 12.6 seconds), 105% (ACT = 156.9 ± 11.0 seconds, PL = 143.8 ± 12.9 seconds), and 100% PV (ACT = 185.7 ± 10.7 seconds, PL = 169.7 ± 12.8 seconds) (P = .01-.04); but there was no difference for the TTE at 90% PV (ACT = 353.5 ± 52.7 seconds, PL = 332.7 ± 54.0 seconds) (P = .08). These findings suggest that the acute ingestion of this preexercise supplement may be an effective strategy for improving anaerobic performance, but appears to have no effect on aerobic power. [ABSTRACT FROM AUTHOR]

Summary: Background & aims: Bioimpedance spectroscopy (BIS) for the estimation of total body water (TBW) has advantages over isotope dilution techniques, including cost, portability, and ease of use. The aim of the current study was to determine the validity of a BIS device (Imp™ SFB7) for tracking changes in overfat and obese individuals. Methods: Sixty overfat and obese men and women (27±8yr, 33.41±3.81%fat) participated in the study. TBW was estimated using BIS and deuterium oxide (D2O) before and after the ten-week intervention. Results: Pre-and post-intervention BIS TBW estimations errors increased as body mass index (BMI), fat mass (FM), and fat-free mass (FFM) increased (p <0.05). Delta values were more accurate than pre- and post-TBW estimations (total error=1.45L). Age significantly influenced pre- and post-TBW errors (p <0.05). Therefore, a regression equation was developed to correct for the pre- and post-BIS-estimated TBW errors: D2O TBW=11.478+0.743(BIS TBW)–2.429(Gender), (Men=1, Women=2). Conclusions: BIS can be considered an accurate tool for tracking changes in TBW regardless of variations in BMI, FM, FFM, or age in both overfat and obese men and women (BMI>24). Employing a BIS TBW equation is suggested over the development of resistivity coefficients based on BMI, FM, FFM or age. [Copyright &y& Elsevier]

The amyloid beta (Aβ) peptide is associated with the neurodegenerative and inflammatory changes in brains affected by Alzheimer's disease (AD). We hypothesized that the enteric nervous system also produces Aβ in an intestinal component of disease. To test this idea, we compared C57BL/6 wild-type (WT) male and female mice to two models of Alzheimer's disease, amyloid precursor protein (APP)/presenilin 1 (PS1) mice and amyloid precursor protein NL-G-F (App NL-G-F ) mice, at 3, 6, and 12 months of age. Brain Aβ plaque deposition in App NL-G-F mice preceded that in the APP/PS1 mice, observable by 3 months. Three-month-old female App NL-G-F mice had decreased intestinal motility compared with WT and APP/PS1 mice. However, 3-month-old female APP/PS1 mice demonstrated increased intestinal permeability compared with WT and App NL-G-F mice. Both sexes of APP/PS1 and App NL-G-F mice demonstrated increased colon lipocalin 2 mRNA and insoluble Aβ 1–42 levels at 3 months. These data demonstrate an unrecognized enteric aspect of disease in 2 different mouse models correlating with the earliest brain changes. • App NL-G-F and amyloid precursor protein/PS1 mice demonstrated sex and age-dependent dysfunction in intestinal motility and permeability, correlating with colonic proinflammatory changes and amyloid beta (Aβ) levels. • Intestinal dysfunction, inflammation, and Aβ changes correlated with the earliest proinflammatory and Aβ changes in the brains of App NL-G-F and amyloid precursor protein/PS1 mice. • This study demonstrated a novel aspect of Alzheimer's disease associated with the intestines during early disease. [ABSTRACT FROM AUTHOR]