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181.
Purpose: To conduct a systematic review of the evidence regarding the efficacy of exercise training in the management of cystic fibrosis (CF).Methods: Articles were found by searching PEDRO, MEDLINE, and CINAHL databases. Included articles involved exercise-related interventions for long-term adaptations (ie, not acute effects of exercise). Articles were excluded if the language was other than English or if other non-exercise interventions were used. Date of publication was not a factor for exclusion. Two independent reviewers evaluated the included articles using Sackett''s levels of evidence and select scoring criteria.Results: Twelve articles were eligible for inclusion. Interventions studied included various aspects of exercise training: anaerobic, aerobic, or resistance training. Study end-points included pulmonary function, aerobic capacity, strength, and health-related quality of life (HRQL).Conclusions: Exercise training in individuals with CF is beneficial, with aerobic and resistance training having the greatest support in the literature for improved aerobic capacity and strength, respectively. Exercise training does not appear to have an effect of improving pulmonary function, but may have a preservation effect. Strong conclusions about improvement in HQRL from exercise training cannot be made. However, greater consistency in measuring this outcome is needed in future trials. There is a paucity of evidence regarding the role of exercise training in reducing hospitalization and health care utilization, and questions raised by this review should be considered in the design of future trials.Key Words: cystic fibrosis, aerobic exercise, review  相似文献   
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The purpose of this study was to compare measures of body size in two samples of youth baseball players with normative data from the United States National Center for Health Statistics (NCHS) growth charts. One sample of youth baseball players participated in a local little league. The second sample of youth baseball players were members of eight of the twelve teams participating in the 1995 Dixie Youth World Series. Normative data for the United States (NCHS) were used as comparative data. Two trained anthropometrists measured standing height, sitting height, lower limb height, upper limb length, arm girth, calf girth, tricep skinfold, and abdomen skinfold on all participants. In both samples, pitchers, short stops, and first basemen were a more highly skilled group and exhibited larger body size (greater standing height, sitting height, lower limb height, upper limb length) than children who played at other positions. The standing height of local little league players was similar to the median of reference data at ages 7, 8, and 9 years. The standing height and weight of skilled players in both samples approximated the 75th percentile for standing height and weight at ages 10, 11, 12, and 13 years. The results suggest that baseball players exhibit larger body size than the normal population at young ages. Body size may be an important criterion used by coaches to select and assign young players to certain positions.  相似文献   
184.
The aim of this study was to determine whether 3 weeks of intermittent normobaric hypoxic exposure at rest was able to elicit changes that would benefit multi-sport athletes. Twenty-two multi-sport athletes of mixed ability were exposed to either a normobaric hypoxic gas (intermittent hypoxic training group) or a placebo gas containing normal room air (placebo group). The participants breathed the gas mixtures in 5-min intervals interspersed with 5-min recovery periods of normal room air for a total of 90 min per day, 5 days per week, over a 3-week period. The oxygen in the hypoxic gas decreased from 13% in week 1 to 10% by week 3. The training and placebo groups underwent a total of four performance tests, including a familiarization and baseline trial before the intervention, followed by trials at 2 and 17 days after the intervention. Time to complete the 3-km run decreased by 1.7%[95% confidence interval (CI) = -0.6 - 3.9%] 2 days after, and by 2.3% (CI = 0.25 - 4.4%) 17 days after, the last hypoxic episode in the training relative to the placebo group. Substantial changes in the training relative to the placebo group also included increased reticulocyte count 2 days (23.5%; CI =-1.9 to 44.9%) and 12 days (14.6%; CI = -7.1 to 36.4%) post-exposure. The effect of intermittent hypoxic training on 3-km performance found in this study is likely to be beneficial, which suggests non-elite multi-sport athletes should expect such training to enhance performance.  相似文献   
185.
The article tests a couple of hypotheses relating to markets where demand is not taken as a given, but subject to sophisticated and encompassing price-building strategies. The study uses a data set that provides quoted dealer prices for medium-sized works of 100 leading visual artists from 1970 to 2004. These data are compared with auction price results for works by the same artists. The study reports significant discrepancies with respect to the relationship between the age of artists and prices paid for their works in the two markets, and with respect to general price developments in the two markets as measured by indices.
Michael HutterEmail:
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186.
We examined the psychological effects of rapid weight loss among a sample of 41 professional jockeys (mean age 30.9 years, s = 7.0). Participants completed the Brunel Mood Scale (BRUMS) and the Eating Attitudes Test-26 (EAT-26) to establish the relationships between rapid weight loss, mood, and attitudes towards eating. These instruments were administered on three occasions: at the jockeys' minimal weight (achieved through rapid weight loss), their optimal riding weight (when they were not excessively restricting their weight and felt healthy), and their relaxed weight (when there were no forthcoming light rides or no rides at all). It was hypothesized that when riding at minimal weight, jockeys would record a more negative mood profile compared with scores recorded at optimal or relaxed weights. The same trend was expected for eating attitudes. These hypotheses were supported as jockeys reported significantly more negative mood profiles and eating attitudes at minimal weight. The EAT-26 scores indicated the presence of disordered attitudes towards eating at this weight. These results suggest that jockeys' endeavours to reach the minimum weight limit stipulated by governing bodies are likely to jeopardize their psychological well-being. Dialogue surrounding the appropriateness of current weight regulations is therefore encouraged.  相似文献   
187.
Workbook reading achievement of five second-grade girls was assessed under two teacher-contact contingencies. Under one contingency, teacher contacts were made during on-task behavior. Under the other contingency, differential reinforcement of an incompatible behavior (DRI) was in effect, with teacher contacts contingent on students' hand-raising behavior. Both reading achievement and time on task were greater under the on-task contingency than under DRI for hand raising.  相似文献   
188.
The alternate-forms and alpha reliabilities of the Teacher Stress Inventory were investigated based on the responses of two groups of 138 teachers. Reliability estimates ranged from .43 to .94 for the TSI subscales and .71 to .94 for the TSI whole scale, indicating high stability and equivalence for the stress factors across immediate, one-day, one-week, and two-week intervals using two different TSI short forms. Between-forms correlations were larger for the immediate sample than they were for the interval samples. Short-form TSI alphas ranged from .76 to .90.  相似文献   
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190.
The Fourth Edition of the Stanford-Binet and the WISC-R were compared as instruments for assessing the intellectual strengths and weaknesses of students classified as learning disabled in the primary and secondary grades. Results found only a 3.28-point difference (p≥.0001) between the S-B Composite score and the WISC-R Full Scale score. Correlations between the four broad areas of the S-B and the three scales of the WISC-R ranged from .494 (S-B Abstract/Visual Reasoning with WISC-R Verbal) to .920 (S-B Composite with WISC-R Full Scale). All correlations were found to be significant. Implications of the research findings were discussed.  相似文献   
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