K. Sucher

Pre-exercise carbohydrate meals: application of glycemic index.

Purpose: The purpose of this study was to compare postprandial glycemic, insulinemic, and physiologic responses to a pre-exercise meal calculated to have a low glycemic index (LGI) with one calculated to have a moderately high glycemic index (HGI); each meal provided three foods totaling 1.5 g carbohydrate/kg body weight. Methods: After an overnight fast, 10 trained cyclists consumed one of the test meals or water 30 min before cycling 2 h at 70% of maximum oxygen uptake (VO 2max ), followed by cycling to exhaustion at 100% of VO 2max . Results: Plasma insulin levels were significantly lower (P< 0.05) after LGI than after HGI through 20 min of exercise. Significantly higher (P < 0.05) respiratory exchange ratios were observed after HGI than after LGI until 2 h of exercise. At that time plasma glucose levels were significantly higher and ratings of perceived exertion lower (P < 0.05) after LGI compared with after HGI. Time to exhaustion was 59% longer after LGI (206.5 ± 43.5 s) than after HGI (129.5 ± 22.8 s). Conclusions: These results suggest a pre-exercise LGI may positively affect maximal performance following sustained exercise. The LGI maintained higher plasma glucose levels at the end of 2 h of strenuous exercise than the HGI, which may have better supported subsequent maximal effort.

Dietary Intake of At-Risk, Free-Living, Elderly Subjects Receiving Meals-on-Wheels and a Dietary Supplement

Abstract LEARNING OUTCOME: To examine the effect of a dietary supplement on the nutrient intake of elderly persons, receiving Meals-on-Wheels (MOW), who are at nutritional risk. The effect of a dietary supplement was examined in a prospective study of elderly subjects receiving MOW, randomly assigned to one of two groups: an intervention group who received a nutrient dense supplement and a control group who received a fruit-flavored, fluid replacement beverage for 6 months. Participants were twenty-six free-living, elderly subjects who were applicants for MOW and determined to be at nutritional risk. At baseline, no significant differences were noted between the two groups for intake of calories, protein, vitamins A and C, B 12 folate, and minerals calcium and iron. When nutrient intake was compared between the control and intervention participants at 6 months, intervention subjects consumed significantly more calories, protein, B 12 , folate, calcium, and iron. Vitamins A and C intakes were not significantly different. Changes in nutrient intake from baseline to 6 months in the intervention group were significantly increased for protein, B 12 , folate, and calcium. No differences were noted for calories, vitamins A and C, and iron. In contrast, mean daily nutrient intake in the control group from baseline to 6 months, showed a significant decrease in intake for B 12 , and iron, although mean intake met the Recommended Dietary Allowance (RDA). No differences were noted in energy intake, protein, vitamins A and C, folate, and calcium. It can be concluded that nutrient intake was improved when nutritionally at-risk elderly persons on MOW also received a dietary supplement.

The reliability of muscle function analysis using different methods of stimulation

BACKGROUND The purpose of our study was to determine the reliability of nonvolitional muscle function analysis (MFA) by determining the day-to-day and within-day reliability of conventional electrical stimulation and a newer, magneto-electrical stimulation method, using standard laboratory methodology. METHODS Ten healthy, human immunodeficiency virus-negative adult men volunteered as subjects. MFA consisted of measuring the maximal relaxation rate, for magneto-electrical stimulation at 1 Hz and conventional electrical stimulation at 20 Hz, and force-frequency ratios using conventional electrical stimulation at 10 Hz:20 Hz and 10 Hz:50 Hz. Within-day and day-to-day reliability were determined by calculating the coefficient of variation (CV) for all subjects. RESULTS Maximal relaxation rate using magneto-electrical stimulation had a significantly lower CV compared with the other nonvolitional MFA methods (p = .002). CONCLUSIONS Maximal relaxation rate using magneto-electrical stimulation was more reliable and technically easier than the other muscle function parameters examined. However, the day-to-day CV of muscle function parameters is larger than traditional nutrition assessment techniques. Development within the field should strive to improve testing techniques so that the reliability of MFA will allow definition of a range of normal values against which an individuals value can be compared. Until this is available, the precision and reliability of MFA restrict its use to research and population studies.

Korean Dietary Habits and Health Beliefs in the San Francisco Bay Area

Abstract According to the 1990 census, nearly 800,000 Korean Americans live in the U.S., with 33% living in California. It is important that health practitioners understand their culturally based food and health habits and changes that may occur after Koreans live in the U.S. Dietary habits, health beliefs and health practices of 195 Korean adults in the San Francisco Bay Area were assessed by a food frequency questionnaire. Relationships between demographic information and food habits, health beliefs and practices were determined. Most subjects (96%) consume rice once a day and kimchi several times a week (80%). Subjects consumed milk products (50%) and tofu products (40%) several times a week. Vegetables are still used more often than meat products. Data on questions concerning use of ginseng products and preferred methods of treating illness were also collected. Ginseng was used by over half the subjects in order to promote health and stamina. A majority of the subjects consumed traditional foods and medicines for minor illnesses (hot ginger, lemon, herb or honey tea, soy bean sprouts, spicy meat, or bone marrow soup, and samgyetang (type of game hen soup). Younger subjects and those with greater length of residence in the U.S. were slightly more likely to follow American food habits. The majority of subjects (51%), however, preferred to use western medicine and hospitals over traditional medical therapies. According to this study, traditional food habits and health beliefs still influence present-day eating patterns and health practices of Koreans surveyed in the San Francisco Bay Area. Thus, dietitians need to be aware of them and adapt dietary recommendations accordingly.

Zinc Adequacy of Preschool Menus: The Implication of Phytate/Zinc Molar Ratios

Abstract Trends towards a more plant-based diet may alter zinc status of groups with marginal zinc intakes, such as children. Careful menu planning by registered dietitians is critical. The objectives of this study were 1) to determine if the planned menus of licensed child care facilities that participated in Child Care Food Program provided adequate amounts of zinc, and 2)to assess the menus for their phytate content, the known modifier of zinc bioavailability. We contacted 180 child care facilities and randomly selected one week planned menus from 18 facilities (10%) for analysis. The menus were analyzed using a subset of the foods from the Nutrient Database for Nationwide Food Surveys, Release 9. The 5-day average intakes of zinc and other selected nutrients were compared against 1/2 and 2/3 of the Recommended Dietary Allowances (RDAs) established for children 4-6 years of age (there are no RDAs available for ages 3-5). Mean Zinc intakes fell below 1/2 and 2/3 of the RDA. To assess zinc bioavailability as affected by phytate, we calculated phytate to zinc molar ratios for all 18 facilities. Our results showed that phytate to zinc molar ratios were below the critical ratio of 10 for all facilities. In conclusion, the zinc content of the meals that were provided to children participating in the selected childcare facilities did not meet the RDA but that the phytate content of the menus did not inhibit the bioavailability of zinc.

Preexercise Carbohydrate Meals: Application of Glycemic Index

Abstract LEARNING OUTCOME: To list physiologic and performance differences following consumption of two preexercise meals of varying glycemic indices. The lowering of plasma glucose can contribute to fatigue in subjects performing strenuous endurance exercise. Plasma glucose may be maintained by preexercise carbohydrate meals. A low glycemic index meal (LGI) may offer an advantage by providing a source of glucose to the blood for a long period of time accompanied by a minimal insulin surge. The purpose of this study was to compare postprandial metabolic, physiologic, and performance responses to a LGI and a moderately high GI meal (HGI), each providing three foods totaling 1.5g carbohydrate per kg body weight. After an overnight fast, 10 male endurance trained cyclists consumed one of the test meals or water 30min prior to cycling 2h at 70% of maximum oxygen uptake (VO2 max) followed by cycling to exhaustion at 100% of VO2 max. Data were analyzed using two-way ANOVA for repeated measures (P

Impact of Malnutrition in Patients with Pneumonia on Length of Stay

Abstract LEARNING OUTCOME: To determine the impact of malnutrition and early nutrition intervention in hospitalized patients with pneumonia on length of stay. Impact of malnutrition in patients with pneumonia on length of stay (LOS) was evaluated retrospectively in a 399-bed local acute-care community hospital. Ninety-five patients were studied from April to December 1995. Median age of the patients was 63 years (28 to 100 years). The patients were classified as well-nourished, borderline, and high-risk malnourished based on dietary history, percent weight loss, anthropometries, visceral protein lab measurement, and medical history. Of the sample population, 22% (n=21) were classified as well-nourished, 46.3% (n=44) as borderline, and 31.6% (n=30) as high-risk malnourished. Relationships between malnutrition and nutrition intervention on LOS were evaluated. There was a significant relation between malnutrition and LOS. The malnourished (borderline and high-risk) had a significantly higher mean LOS (7.2 ± 3.2 and 9.9 ± 4.0) compared to the well-nourished group (4.1 ± 1.1), (p