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31.
Duggan A Caldera D Rodriguez K Burrell L Rohde C Crowne SS 《Child abuse & neglect》2007,31(8):801-827
OBJECTIVES: To assess the impact of a voluntary, paraprofessional home visiting program in preventing child maltreatment and reducing the multiple, malleable psychosocial risks for maltreatment for which families had been targeted. METHODS: This collaborative, experimental study focused on 6 Healthy Families Alaska (HFAK) programs; 325 families were enrolled in 2000-2001, randomized to intervention and control groups, and interviewed to measure baseline attributes. Follow-up data were collected when children were 2 years old (85% follow-up rate). Outcomes included maltreatment reports, measures of potential maltreatment and parental risks, for example, poor mental health, substance use, and partner violence. HFAK records were reviewed to measure home visiting services. Home visitors were surveyed to measure perceived effectiveness and training adequacy. RESULTS: Parental risks were common at baseline, and one-sixth of families had a substantiated child protective services report in the child's first 2 years of life. There was no overall program effect on maltreatment reports, and most measures of potential maltreatment. Home visited mothers reported using mild forms of physical discipline less often than control mothers. The groups were similar in their use of more severe forms of physical discipline. There was no program impact on parental risks. There was no impact on outcomes for families with a 'high dose' of home visiting. Home visitors often failed to address parental risks and seldom linked families with community resources. Contradictions in the model compromised effectiveness. CONCLUSIONS: The program did not prevent child maltreatment, nor reduce the parental risks that had made families eligible for service. Research is needed to develop and test strategies to improve the effectiveness of home visiting. 相似文献
32.
Kerry S. Courney Laura Q. Rogers Kristin L. Campbell Jeff K. Vallance Christine M. Friedenreich 《北京体育大学学报》2016,39(2):40-48
摘要:今天的美国有1 400万的癌症存活者,其中的很多存活者中都接受了多种治疗,包括手术、放疗、化疗、靶向治疗等。这些治疗能够延长生存时间,但同时也会带来很多急慢性的副作用,危害健康,影响生活质量。体力活动(PA)与癌症生存这一领域发展迅速,主要研究PA对癌症患者的影响。基于该领域的研究进展,提出了以下10大研究问题:1)PA能够降低癌症复发风险、和/或提高存活吗?2)PA能够影响癌症治疗决策、完成率、和/或患者对治疗的反应吗?3)癌症存活者的最佳运动处方是什么?4)静坐少动行为对癌症存活者有何影响?5)癌症存活者最有效的体力活动干预方案是什么?6)哪些癌症会影响病人对PA的反应?7)癌症存活者进行体力活动时需要注意的安全问题有哪些?8)哪些具体的癌症症状可以由PA解决?9)对于癌症晚期患者,体力活动还有何作用?10)如何将体力活动研究结果转化到临床和社区肿瘤实践中来?上述问题的回答至关重要,这不仅关系到体力活动和癌症存活这一研究领域的发展,更重要的是,能够为每年数百万新诊断为癌症的病人、正在接受癌症治疗的病人、治疗结束处于恢复中的病人或是那些正在与晚期癌症抗争的病人带来福音。 相似文献
33.
Jedlic B Hall N Munroe-Chandler K Hall C 《Research quarterly for exercise and sport》2007,78(4):351-363
To investigate whether coaches encourage their athletes to use imagery, two studies were undertaken. In the first, 317 athletes completed the Coaches' Encouragement of Athletes' Imagery Use Questionnaire. In the second, 215 coaches completed a slightly modified version of this questionnaire. It was found that coaches and athletes generally agreed on the relative frequency with which coaches encourage athletes to use imagery across the 4 Ws (i.e., where, when, why, and what). Coaches promoted imagery use more in conjunction with competition than training and injury rehabilitation, and higher-level coaches encouraged imagery use far more than their recreational counterparts. In addition, the level of athlete being coached had a major impact on how much or little coaches encouraged their athletes to use imagery. Coaches encouraged higher level athletes (i.e., international, national, varsity) to use imagery more than club and recreational athletes. 相似文献
34.
De Cocker K Cardon G De Bourdeaudhuij I 《Research quarterly for exercise and sport》2007,78(5):429-437
Pedometer-determined physical activity (PA) levels in Belgian adults were provided and compared to PA scores reported in the International Physical Activity Questionnaire (IPAQ). The representative sample (N=1239) of the Belgian population took on average 9655 (4526) steps/day. According to pedometer indices 58.4% were insufficiently active. Steps/day differed significantly between gender (F = 5.0, p = .026), age groups (F = 3.3, p = .01), employment status (F = 6.2, p = .013), and days of monitoring (F = 7.4, p = .007). Steps/day were negatively correlated to the time spent sitting and positively to PA at work, in transport, and in leisure time (p < .001). Steps data can discriminate between PA levels reported in the IPAQ. Belgian population pedometer-determined PA levels are higher than those reported in samples of the United States; however, there is a wide distribution of ambulatory behavior 相似文献
35.
The home advantage is a widely acknowledged sporting phenomenon, especially in association football. Here, we examine the second leg home advantage, an effect that is discussed in the public domain but which has received very little scientific attention. The second leg home advantage effect occurs when on average teams are more likely to win a two-stage knock-out competition when they play at home in the second leg. That is, both teams have a home advantage but this advantage is significantly greater for the team that plays at home second. Examining data from three different European Cup football competitions spanning 51 years, we show that the second leg home advantage is a real phenomenon. The second leg home team has more than a 50% probability to qualify for the next round in the competition even after controlling for extra time and team ability as possible alternative explanations. The second leg home advantage appears, however, to have decreased significantly over the past decade. Possible reasons for its existence and subsequent decline are presented. 相似文献
36.
Comparison of two Actigraph models for assessing free-living physical activity in Indian adolescents
Corder K Brage S Ramachandran A Snehalatha C Wareham N Ekelund U 《Journal of sports sciences》2007,25(14):1607-1611
This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length. 相似文献
37.
In this study, we examined the time course of changes in running economy following a 30-min downhill (-15%) run at 70% peak aerobic power (VO2peak). Ten young men performed level running at 65, 75, and 85% VO2peak (5 min for each intensity) before, immediately after, and 1 - 5 days after the downhill run, at which times oxygen consumption (VO2), minute ventilation, the respiratory exchange ratio (RER), heart rate, ratings of perceived exertion (RPE), and blood lactate concentration were measured. Stride length, stride frequency, and range of motion of the ankle, knee, and hip joints during the level runs were analysed using high-speed (120-Hz) video images. Downhill running induced reductions (7 - 21%, P < 0.05) in maximal isometric strength of the knee extensors, three- to six-fold increases in plasma creatine kinase activity and myoglobin concentration, and muscle soreness for 4 days after the downhill run. Oxygen consumption increased (4 - 7%, P < 0.05) immediately to 3 days after downhill running. There were also increases (P < 0.05) in heart rate, minute ventilation, RER, RPE, blood lactate concentration, and stride frequency, as well as reductions in stride length and range of motion of the ankle and knee. The results suggest that changes in running form and compromised muscle function due to muscle damage contribute to the reduction in running economy for 3 days after downhill running. 相似文献
38.
Tachibana K Yashiro K Miyazaki J Ikegami Y Higuchi M 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(1):44-58
Although it is clear that rowers have a large muscle mass, their distribution of muscle mass and which of the main motions in rowing mediates muscle hypertrophy in each body part are unclear. We examine the relationships between partial motion power in rowing and muscle cross-sectional area of the thigh, lower back, and upper arms. Sixty young rowers (39 males and 21 females) participated in the study. Joint positions and forces were measured by video cameras and rowing ergometer software, respectively. One-dimensional motion analysis was performed to calculate the power of leg drive, trunk swing, and arm pull motions. Muscle cross-sectional areas were measured using magnetic resonance imaging. Multiple regression analyses were carried out to determine the association of different muscle cross-sectional areas with partial motion power. The anterior thigh best explained the power demonstrated by leg drive (r2 = 0.508), the posterior thigh and lower back combined best explained the power demonstrated by the trunk swing (r2 = 0.493), and the elbow extensors best explained the power demonstrated by the arm pull (r2 = 0.195). Other correlations, such as arm muscles with leg drive power (r2 = 0.424) and anterior thigh with trunk swing power (r2 = 0.33 5), were also significant. All muscle cross-sectional areas were associated with rowing performance either through the production of power or by transmitting work. The results imply that rowing motion requires a well-balanced distribution of muscle mass throughout the body. 相似文献
39.
Prediction of maximal oxygen uptake in sedentary males from a perceptually regulated, sub-maximal graded exercise test 总被引:2,自引:0,他引:2
The purpose of this study was to assess the validity of predicting the maximal oxygen uptake (VO2(max)) of sedentary men from sub-maximal VO2 values obtained during a perceptually regulated exercise test. Thirteen healthy, sedentary males aged 29-52 years completed five graded exercise tests on a cycle ergometer. The first and fifth test involved a graded exercise test to determine VO2(max). The two maximal graded exercise tests were separated by three sub-maximal graded exercise tests, perceptually regulated at 3-min RPE intensities of 9, 11, 13, 15, and 17 on the Borg ratings of perceived exertion (RPE) scale, in that order. After confirmation that individual linear regression models provided the most appropriate fit to the data, the regression lines for the perceptual ranges 9-17, 9-15, and 11-17 were extrapolated to RPE 20 to predict VO2(max). There were no significant differences between VO2(max) values from the graded exercise tests (mean 43.9 ml x kg(-1) x min(-1), s = 6.3) and predicted VO2(max) values for the perceptual ranges 9-17 (40.7 ml x kg(-1) x min(-1), s = 2.2) and RPE 11-17 (42.5 ml x kg(-1) x min(-1), s = 2.3) across the three trials. The predicted VO2(max) from the perceptual range 9-15 was significantly lower (P < 0.05) (37.7 ml x kg(-1) x min(-1), s = 2.3). The intra-class correlation coefficients between actual and predicted VO2(max) for RPE 9-17 and RPE 11-17 across trials ranged from 0.80 to 0.87. Limits of agreement analysis on actual and predicted VO2 values (bias +/- 1.96 x S(diff)) were 3.4 ml x kg(-1) x min(-1) (+/- 10.7), 2.4 ml x kg(-1) x min(-1) (+/- 9.9), and 3.7 ml x kg(-1) x min(-1) (+/- 12.8) (trials 1, 2, and 3, respectively) of RPE range 9-17. Results suggest that a sub-maximal, perceptually guided graded exercise test provides acceptable estimates of VO2(max) in young to middle-aged sedentary males. 相似文献
40.
The aims of this study were twofold: (1) to determine whether open feedback (i.e. the ability to hear or see the scores of colleague judges after each performance) would lead judges in gymnastics to conform with their colleagues, and (2) to identify the underlying process on which this conformity is based. Twenty-three certified Flemish judges in women's gymnastics were randomly divided into panels of a maximum of five judges. These panels had to rate the same 30 videotaped individual vaults: 15 in phase 1 and 15 in phase 2. Two independent variables were orthogonally manipulated: feedback (or no feedback) during phase 1 and feedback (or no feedback) during phase 2. The results of phase 1 revealed that the variation between the judges' scores was less within panels that had received feedback than within panels that had not received feedback. We therefore conclude that the availability of feedback elicits conformity among gymnastic judges. The results of phase 2 indicated that this conformity continued even when feedback was no longer provided, suggesting that the observed conformity was based on informational influencing (i.e. because of uncertainty about the correct responses) and not on normative influencing (i.e. out of fear of standing out in the group). 相似文献