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The relationship of scapulothoracic motion to glenohumeral motion, commonly referred to as the scapulohumeral rhythm, has been the subject of numerous investigations. The purpose of this study was to assess the effects of localized muscular fatigue on three-dimensional scapulothoracic motion and the resulting scapulohumeral rhythm during elevation of the humerus in the plane of the scapula. A six-degree-of-freedom digitizing system (Metrecom(TM)) was used to define scapular and trunk reference frames, and three-dimensional Eulerian angles were determined for scapular motion for 0-135 degrees of humeral elevation before and after fatigue of the upper and lower trapezius muscles. Local muscle fatigue was determined using spectral analysis of electromyographic signals for the upper and lower trapezius muscles. The results demonstrated an average of 22% decrease in the median frequencies of the muscles sampled following resistive exercise, suggesting a state of local muscle fatigue. Concomitant with the fatigue was a selective decrease in scapulothoracic motion about two of the three scapular axes. RELEVANCE: Occupational and recreational conditions often require repetitive overhead elevations of the arms, resulting in muscular fatigue and various pathologies. During repetitive arm elevations the scapulohumeral rhythm or synchronization between the humerus and the scapula is balanced to allow the most efficient elevation of the arm. A better understanding of this much-discussed scapulohumeral rhythm and the changes induced by muscular fatigue may provide insight into the pathomechanics associated with shoulder dysfunction. 相似文献
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Background: This study explored eating habits, nutrient intake, and blood vitamin and mineral levels to determine whether
severely obese subjects (BMI 40-50 kg m−2) post-vertical banded gastroplasty (VBG) or gastric bypass Roux-en-Y (GBR) are at risk of developing compounded under-nutrition.
Methods: A dietary follow-up of 36 VBG and 19 GBR was maintained for 18 months via 7-day food intake diaries and 24-h recalls.
Food intake was analysed for energy and nutrient composition and for its relative amount to recommended dietary allowances
(RDA). Results: Weight loss was greatest during the first 6 months, continued at a slower rate for the next 6 months, nearly
ceasing thereafter. The results following GBR were not substantially different from those following VBG 18 months postoperatively.
The median weight loss at 1 year postoperatively was 48, 46, 48 and 36 kg; expressed as residual excess body weight: 0.2,
16, 13 and 22% for GBR Men, Women, VBG Men, Women, respectively. According to the classification proposed by Reinhold, all
subjects achieved excellent treatment outcomes 18 months postoperatively. Despite the relatively low reported energy intake
(20-50% below RDA), no correlation was found between rate of weight loss and energy intake at 6 months postoperatively. The
intake of most vitamins and minerals was below 50% of RDA during the 18 months follow-up. The increase in energy intake did
not improve the level of the nonenergy-contributing nutrients. Compliance to multivitamin and mineral supplement intake deteriorated
with time. Conclusion: The low to within-normal range of blood vitamin and mineral levels 12 months postoperatively suggests
the slow development of subclinical nutritional deficiency which could jeopardize the subjects' long-term health status. 相似文献
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John P. Sciacca PhD MPH CHES David A. Dube MPH RD Brenda L. Phipps BS CLE Michael I. Ratliff PhD 《Journal of community health》1995,20(6):473-490
This study was undertaken to determine the effects of a partner-support, incentive-baed educational program on breast feeding knowledge, attitudes and support and to examine the relationship between feeding intentions and feeding behavior among low-income women. Women who expressed a willingness to participate in the intervention were randomly assigned to intervention and usual breast feeding (control) groups. Sixty-eight primipara women, with expected due dates between May and December, 1992, volunteered to participate in the study. Of these, 34 were randomly assigned to each of the two groups. Approximately 81 percent of the women completed the study, leaving n=29 in the control group and n-26 in the intervention group. The intervention consisted of special incentives (prizes) for women and their partners to participate in several breast feeding education and promotion activities. Intervention group women and their partners experienced positive changes in breast feeding knowledge and attitudes. Furthermore, the intervention seemed to have influenced more women in the treatment group to breast feed despite their prenatal feeding intentions. In addition, the partners of intervention group women were perceived to be more supportive of, breast feeding than control group partners. These findings suggest that incentives, such as donated prizes, can be used to attract lower socioeconomic group women and their partners to breast feeding promotion interventions. Participation in such interventions can produce positive changes in breast feeding knowledge, attitudes, and support, and can have a dramatic effect in promoting breast feeding.This study was supported through contract no. 59-3198-1-050 from the Food and Nutrition Service, U.S. Department of Agriculture. 相似文献
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SOO-KYUNG LEE PhD RD JEFFEREY SOBAL PhD MPH EDWARD A FRONGILLO Jr PhD 《Journal of the American Dietetic Association》1999,99(9):1084-1089
OBJECTIVE: Examine variation in dietary practices and nutritional intakes of Korean Americans at different acculturation levels. DESIGN: Cross-sectional mail survey. SUBJECTS/SETTING: US national sample of 348 Korean Americans (46% of the Korean American sample to whom questionnaires were delivered). STATISTICAL ANALYSIS PERFORMED: Analysis of variance, Pearson correlation, Spearman rank correlation, chi 2 test, and multiple regression analysis. RESULTS: Korean Americans who were more acculturated consumed more American food and less Korean food. American foods such as oranges, low-fat milk, bagels, tomatoes, and bread were consumed regularly by Korean Americans; Korean foods such as rice, kimchi, garlic, green onions, and Korean soup were also consumed regularly. American foods were adopted the most at breakfast and the least at dinner. Bicultural people regularly incorporated more different types of foods into their diet. Despite significant differences in dietary practices, dietary quality did not vary by acculturation status. APPLICATION/CONCLUSIONS: Acculturation was influential in the dietary patterns of Korean Americans. Specific information about Korean diet related to acculturation status can be used by dietitians who work with Korean Americans. Dietitians can benefit from gathering and applying specific information about Korean diets and diets of other ethnic groups; they also need to recognize the changing nature of dietary patterns as acculturation occurs. 相似文献