The impact of public transportation strikes on use of a bicycle share program in London: interrupted time series design

Objective

To investigate the immediate and sustained effects of two London Underground strikes on use of a public bicycle share program.

Methods

An interrupted time series design was used to examine the impact of two 24 hour strikes on the total number of trips per day and mean trip duration per day on the London public bicycle share program. The strikes occurred on September 6th and October 4th 2010 and limited service on the London Underground.

Results

The mean total number of trips per day over the whole study period was 14,699 (SD = 5390) while the mean trip duration was 18.5 minutes (SD = 3.7). Significant increases in daily trip count were observed following strike 1 (3864: 95% CI 125 to 7604) and strike 2 (11,293: 95% CI 5169 to 17,416).

Conclusions

Events that greatly constrain the primary motorised mode of transportation for a population may have unintended short-term effects on travel behaviour. These findings suggest that limiting transportation options may have the potential to increase population levels of physical activity by promoting the use of cycling.     

Cardiac response to progressive cycle exercise in moderately obese adolescent females

PURPOSE: To assess cardiac responses to exercise and cardiac functional capacity in moderately obese adolescent females. METHODS: Thirteen healthy females (mean age 13.6 +/- 1.5 years) with a body mass index from 30 to 43 kg per m(2) underwent maximal cycle testing. Cardiac responses were measured by Doppler echocardiogram, and gas exchange variables were determined with open circuit spirometry. Data were analyzed by independent Student's t-tests. RESULTS: Peak oxygen uptake relative to height(3.0) was significantly greater in the obese (570 +/- 90 ml m(-3)) compared to the nonobese controls (485 +/- 60 ml m(-3)). This difference was explained by a higher peak cardiac output (4.50 +/- 1.06 L m(-3) vs. 3.81 +/- 58 L m(-3)) and stroke volume (24 +/- 5 ml m(-3) vs. 19 +/- 3 ml m(-3)) in the obese. Maximal cardiac index was similar in the two groups. There was no evidence of myocardial dysfunction during exercise in either group. CONCLUSIONS: Low aerobic fitness in obese adolescents as indicated by depressed peak VO(2) per kg body mass and limited endurance performance does not reflect decreased cardiac functional capacity.     

不同出行方式PM_(2.5)个体暴露水平的比较研究

目的在不同浓度大气PM_(2.5)水平下,比较不同出行方式的PM_(2.5)个体暴露水平,并进一步比较地铁站不同位置的PM_(2.5)浓度,以期为城市居民选择适宜的出行方式提供科学依据。方法于2015年12月30日至2016年1月4日,选择北京市城区的某条路线作为研究地点,使用便携式PM_(2.5)监测仪同时测量步行、乘坐公交车和地铁3种出行方式的PM_(2.5)个体暴露水平;对地铁站台、安检处和地铁车厢内的PM_(2.5)浓度进行同步监测并比较。结果在同一研究时期,步行、乘坐公交车和地铁测得的PM_(2.5)个体暴露浓度均值分别为219.34、209.61、167.56μg/m3。当大气PM_(2.5)浓度较低时(≤60μg/m3),乘坐地铁的PM_(2.5)个体暴露水平高于步行和乘坐公交车;当大气PM_(2.5)浓度较高时(100μg/m3),乘坐地铁的个体PM_(2.5)暴露水平明显低于步行和公交车,差异均有统计学意义(P0.05)。监测期间地铁站台、安检处和车厢内的PM_(2.5)浓度均值分别为196.90、170.20、136.82μg/m3。结论在不同的大气PM_(2.5)污染水平下,不同出行方式的人群PM_(2.5)个体暴露水平不同。     

1997—2009年我国9省区18～49岁成年居民身体活动状况及变化趋势研究

目的研究1997—2009年我国9省区18~49岁成年居民身体活动状况及变化趋势。方法利用＂中国健康与营养调查＂资料中选取1997、2000、2004、2006和2009年5轮调查有完整身体活动数据的18~49岁健康成年居民25 507人作为研究对象,计算该人群每周身体活动量。结果男、女性成年居民身体活动量从1997年的358.7 metabolic equivalent-hours（MET-hrs）/周和403.1 MET-hrs/周分别下降至2009年的255.8 METhrs/周和249.0 MET-hrs/周;城市、农村成年居民身体活动量从1997年的311.1 MET-hrs/周和416.9 MET-hrs/周分别下降至2009年的181.4 MET-hrs/周和285.3 MET-hrs/周,男性、女性、城市、农村成年居民身体活动量在不同调查年间比较差异均有统计学意义（P〈0.01）。成年居民以静态活动为主要休闲方式的人群比例从1997年的89.0%升高至2009年的91.2%;以步行和骑自行车为主要出行方式的人群比例从1997年的70.0%下降至2009年的47.1%,成年居民休闲方式及出行方式的人群比例在不同调查年间比较差异均有统计学意义（P〈0.01）。结论我国9省区18~49岁成年居民身体活动量发生显著变化,该人群身体活动量的大幅度下降值得关注。     

Web-based interventions to promote physical activity by older adults: promising perspectives for a public health challenge

Regular physical activity is associated with a wide range of health benefits. As population age, promotion of physical activity should specifically target older adults, an expanding group involving potential higher health care costs in the near future. Innovative interventions focusing on physical activity behaviors of senior adults exposed promising results, most recently through the use of the Internet. If seniors and Internet are generally considered as two opposite concepts, arguments in favour of bringing them together in a public health perspective have been identified by the recent literature. Older adults are the fastest growing group of Internet users and are more prone than younger to use it for health-related subjects. Web-based interventions are effective in many health promotion sectors, including physical activity. This is particularly true when interventions target the environmental determinants of each senior citizen and are specifically designed for this population. Those early research findings must clearly be extended, particularly regarding to the long term effects of Web-based physical activity interventions. Solutions that will reduce the high dropout rate recorded in the existing literature must also be considered as a priority in order to ensure the development of this forward-looking field of research.     

After-effects of night work on physical performance capacity and sleep quality in relation to age

Summary The after-effects of night work on physical performance capacity and sleep quality were studied. Ten younger (age 34 years) and eight older (age > 34 years) experienced shift workers were examined. Subjects performed cycle ergometer tests at an exercise intensity requiring 70% of the individual maximal oxygen uptake. Two conditions were studied: a baseline condition, i.e. the last day of a 4 days-off period, and a recovery condition after a period of seven consecutive night shifts, i.e. the second day-off after the night-shift period (32 h after leaving the night-shift period). Sleep quality of the sleep period preceding the test was also measured for both conditions. During the recovery condition the endurance time (i.e. time to exhaustion) was reduced by an average of 20% (–160s, P < 0.05) for the older shift workers only. In both age groups exercise ventilation, heart rate, oxygen uptake, perceived exertion and sleep quality remained unaffected. These findings support the hypothesis that the aging shift worker is faced with increasing complaints, even after the night-shift period. However, to clarify the mechanisms responsible for these after-effects of night work, further extensive studies must be designed.     

Impact of a community-based exercise programme on physical fitness in middle-aged and older patients with type 2 diabetes

ObjectivesPhysical fitness is related to all-cause mortality, quality of life and risk of falls in patients with type 2 diabetes. This study aimed to analyse the impact of a long-term community-based combined exercise program (aerobic + resistance + agility/balance + flexibility) developed with minimum and low-cost material resources on physical fitness in middle-aged and older patients with type 2 diabetes.MethodsThis was a non-experimental pre-post evaluation study. Participants (N = 43; 62.92 ± 5.92 years old) were engaged in a community-based supervised exercise programme (consisting of combined aerobic, resistance, agility/balance and flexibility exercises; three sessions per week; 70 min per session) of 9 months’ duration. Aerobic fitness (6-Minute Walk Test), muscle strength (30-Second Chair Stand Test), agility/balance (Timed Up and Go Test) and flexibility (Chair Sit and Reach Test) were assessed before (baseline) and after the exercise intervention.ResultsSignificant improvements in the performance of the 6-Minute Walk Test (Δ = 8.20%, p < 0.001), 30-Second Chair Stand Test (Δ = 28.84%, p < 0.001), Timed Up and Go Test (Δ = 14.31%, p < 0.001), and Chair Sit and Reach Test (Δ = 102.90%, p < 0.001) were identified between baseline and end-exercise intervention time points.ConclusionsA long-term community-based combined exercise programme, developed with low-cost exercise strategies, produced significant benefits in physical fitness in middle-aged and older patients with type 2 diabetes. This supervised group exercise programme significantly improved aerobic fitness, muscle strength, agility/balance and flexibility, assessed with field tests in community settings.     

Pre-return to work consultation and therapeutic part-time work: Cross-sectional study on level of knowledge and use by general practitioners in France

BackgroundIn France, general practitioners (GPs) may use two tools specifically designed to help employees who experience difficulties in returning to work after sick leave: the pre-return-to-work (PRW) medical consultation and therapeutic part-time (TPT) work.ObjectivesThe objective was to investigate the level of knowledge and use of these two tools by GPs in Maine-et-Loire, France.MethodsThis cross-sectional study was performed using a telephone questionnaire to evaluate the level of knowledge of GPs and the use of these two tools in patients having difficulties returning to work.ResultsAmong the 200 randomly selected GPs, 122 responded (response rate: 61%). More than half of the interviewed GPs declared they ‘often’ (46%) or ‘always’ (14%) contacted the occupational physician in these situations. Moreover, 62.2% and 32.7% believed that they had a ‘vague’ or ‘very good’ level of knowledge, and 41% and 51% declared either ‘frequent’ or ‘regular’ level of use of the PRW medical consultation, respectively. Regarding TPT work, 47% and 53% reported a ‘very good’ or ‘vague’ level of knowledge, and 41% and 51% a ‘frequent’ or ‘regular’ level of use, respectively. GPs who had a better level of knowledge of this tool reported a higher level of use (p < 0.001).ConclusionThis study shows that while the level of knowledge and use of the PRW medical consultation and TPT work is good, it is not optimal. This could be improved by organising training courses for GPs. Obstacles to their wider use could be investigated further in a qualitative study.     

CRF阻断镉对大鼠脾淋巴细胞免疫毒性的体外实验研究

目的：探讨体外镉的免疫功能抑制过程中促肾上腺皮质激素释放因子（CRF）的修饰调节作用。方法：离体培养大鼠脾淋巴细胞,用^3H-TdR掺入法测定分别在给氯化镉、CRF及两者联合作用条件下的T、B淋巴细胞的增殖转化功能。结果：镉抑制大鼠脾淋巴细胞的增殖转化,各染镉实验组T、B淋巴细胞增殖指数低于对照组（P＜0．05）;且有随剂量升高而而降低的趋势;1．0－100．0nmol/L CRF标准浓度组T、B淋巴细胞增殖指数明显高于对照组（P＜0．05）;当以1．0nmol/L CRF与5－20 μmol/L氯化镉联合作用时两种免疫细胞的增殖功能依然明显受到刺激,各实验组^3H-TdR掺入率高于对照组（P＜0．05）。结论：体外CRF能增强免疫细胞增殖活性并可阻断镉对T、B淋巴细胞的增殖抑制毒性。