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Abstract Background β-Alanine (βA) has been shown to improve performance during cycling. This study was the first to examine the effects of βA supplementation on the onset of blood lactate accumulation (OBLA) during incremental treadmill running. Methods Seventeen recreationally-active men (mean ± SE 24.9 ± 4.7 yrs, 180.6 ± 8.9 cm, 79.25 ± 9.0 kg) participated in this randomized, double-blind, placebo-controlled pre/post test 2-treatment experimental design. Subjects participated in two incremental treadmill tests before and after 28 days of supplementation with either βA (6.0 g·d-1)(βA, n = 8) or an equivalent dose of Maltodextrin as the Placebo (PL, n = 9). Heart rate, percent heart rate maximum (%HRmax), %VO2max@OBLA (4.0 mmol.L-1 blood lactate concentration) and VO2max (L.min-1) were determined for each treadmill test. Friedman test was used to determine within group differences; and Mann-Whitney was used to determine between group differences for pre and post values (p < 0.05). Results The βA group experienced a significant rightward shift in HR@OBLA beats.min-1 (p < 0.01) pre/post (161.6 ± 19.2 to 173.6 ± 9.9) but remained unchanged in the PL group (166.8 ± 15.8 to 169.6 ± 16.1). The %HRmax@OBLA increased (p < 0.05) pre/post in the βA group (83.0% ± 9.7 to 88.6% ± 3.7) versus no change in the PL group (86.3 ± % 4.8 to 87.9% ± 7.2). The %VO2max@OBLA increased (p < 0.05) in the βA group pre/post (69.1 ± 11.0 to 75.6 ± 10.7) but remained unchanged in the PL group (73.3 ± 7.3 to 74.3 ± 7.3). VO2max (L.min-1) decreased (p < 0.01) in the βA group pre/post (4.57 ± 0.8 to 4.31 ± 0.8) versus no change in the PL group (4.04 ± 0.7 to 4.18 ± 0.8). Body mass kg increased (p < 0.05) in the βA group pre/post (77.9 ± 9.0 to 78.3 ± 9.3) while the PL group was unchanged (80.6 ± 9.1 to 80.4 ± 9.0). Conclusions βA supplementation for 28 days enhanced sub-maximal endurance performance by delaying OBLA. However, βA supplemented individuals had a reduced aerobic capacity as evidenced by the decrease in VO2max values post supplementation.

Childhood obesity remains a problem in the United States. Preschool teachers can help to attenuate it but need to have the confidence or self-efficacy to provide healthy practices. Therefore, the purpose of this study was to (a) develop and validate a preschool teacher self-efficacy tool to examine teachers' confidence in addressing the nutrition and physical activity needs of children in their care and (b) examine relationships between teachers' self-efficacy and knowledge of healthy nutrition and physical activity practices. Instrument design included examination of related literature and review by 12 subject matter experts. Two hundred seventy-three early childhood professionals submitted a 58-item questionnaire with 48 self-efficacy items in four domains of healthy practices for the preschool classroom; the remaining 10 items reflected knowledge of healthy practices. Two hundred fourteen professionals completed the questionnaire. A principle components factor analysis supported a five-factor self-efficacy scale (three of the original domains and one domain split into two factors) with 46 items. Knowledge of healthy practices and age of the professionals predicted overall self-efficacy. Results indicated evidence of validity for this new assessment tool to assess early childhood professionals' self-efficacy toward healthy practices in preschool classrooms.

Child care teachers and staff are important influences on preschoolers' nutrition and physical activity habits, and their views may be influenced by education level, years of field experience, and program involvement. For the 360 participants surveyed, responses on 5 of 18 survey items significantly differed by education level (e.g., less education led to more agreement about difficulty with foods at school). Years of field experience significantly differed on three items, such as less experience led to agreeing that government guidelines were helpful. Perceptions significantly differed between Head Start and other programs' staff on two items about food and activity school practices. Following the survey, 32 Head Start professionals participated in focus groups, yielding 16 main ideas among three broad themes involving teachers' roles, perceptions, and strategies concerning nutrition and physical activity practices. Roles revolved around use of Head Start guidelines and checklists. Perceptions included (1) mealtime routines, (2) menus, (3) planned physical activity time, and (4) sedentary lifestyles. Strategies included (1) posting weekly menus and lesson plans, (2) working with the dietitian for classroom ideas, (3) using music to encourage movement, and (4) having large motor areas. Recommendations for future research, policy initiatives, and educational implications are suggested. (Contains 5 tables.)

Background: Adults over the age of 65 years are more prone to gastroesophageal reflux and, as such, are commonly prescribed proton pump inhibitors (PPIs). PPIs inhibit gastric acid secretion which can have adverse effects on vitamin B12 absorption. This quasi-experimental study was conducted to determine whether chronic use (≥1 year) of proton pump inhibitors (PPIs) results in decreased vitamin B12 in adults aged 68-94 years, as indicated by increased urinary methylmalonic acid (uM-MA). Methods: Fifteen men and women who had been using PPIs daily for a minimum of one year were recruited. Fifteen subjects not using PPIs were age (±3 years) and gender matched to the subjects taking PPIs. Tissue stores of vitamin B12 were determined using uM-MA. Results: The majority of subjects in this study resided in assisted care living facilities (55.66%) and the remaining subjects (43.33%) were free living. There were no significant differences in uM-MA levels between those using PPIs (Mdn = 1.1 μg uM-MA/mg creatinine), and those not using PPIs (Mdn = 1.1 μg uM-MA/mg creatinine) (p = 0.75). Conclusion: Chronic use of PPIs did not alter vitamin B12 in healthy individuals aged 68-94 years. Larger studies are indicated to validate these findings. [ABSTRACT FROM AUTHOR]