Promoting stair climbing: stair-riser banners are better than posters... sometimes

OBJECTIVE

Stair-riser banners are twice as effective as posters in encouraging stair climbing in shopping centres. This study tested the effectiveness of stair-riser banners in an English train station in 2006-2007.

METHOD

The train station had a 39-step staircase and an adjacent escalator. Baseline observations (3.5 weeks) were followed by 10.5 weeks of a banner intervention supplemented with 3 weeks of a poster intervention. Both poster and banner featured the message 'Stair climbing burns more calories per minute than jogging. Take the stairs'. Ascending escalator and stair users (N=36,239) were coded for gender.

RESULTS

Analyses, controlling for effects of gender and pedestrian traffic volume, revealed no significant change in stair climbing between baseline (40.6%) and the banner intervention (40.9%; p=0.98). Addition of the poster increased stair climbing (44.3%; OR=1.36, 95% CIs 1.16-1.60, p<0.001), with the effect reduced at higher pedestrian traffic volumes.

CONCLUSION

While stair-riser banners had no effect, the poster intervention increased stair climbing. The high pedestrian volumes as the wave of disembarking passengers seek to leave the station would have obscured the visibility of the banner for many commuters. Thus stair-riser banners appear unsuitable point-of-choice prompts in stations where pedestrian traffic volume is high.

Elevator-related injuries to children in the United States, 1990 through 2004

This study describes the epidemiology of elevator-related injuries among children in the United States from 1990 to 2004. A retrospective cohort analysis was performed using data from the National Electronic Injury Surveillance System of the US Consumer Product Safety Commission. Reported cases were used to project national estimates. An estimated 29 030 elevator-related injuries occurred among children in the United States during 1990 to 2004. The mean age was 8.1 years (SD, 6.1 years), with 53.3% of injuries among boys. The overall injury rate was 2.5 injuries per 100,000 population. The injury rate for children aged 0-4 years was 4.2 per 100,000 population, and for children aged 5-19 years the injury rate was 1.9 per 100,000 population. The most frequent cause of injury was the elevator door closing on a body part, the most frequently injured body region was the upper extremity, and soft-tissue injuries were the most frequent type of injury. Children should be closely supervised on or near elevators to reduce the risk of injury.

A poster-based intervention to promote stair use in blue- and white-collar worksites

OBJECTIVE

Previous studies have generally shown the effectiveness of prompts to promote stair use in worksites that mainly consist of white-collar workers. The present study tested whether an intervention using prompts is effective in stimulating stair use in two types of worksites: one consisting mainly of white-collar workers and one mainly of blue-collar workers.

METHOD

In 2005, elevator and stair use (stair climbing and descent) was monitored in two types of worksites in the Netherlands, namely one office building (n=150 white-collar workers) and one paper factory (n=800 blue-collar workers). The study used a simple time-series design of collecting data in three waves: before, during and after implementation of posters containing prompts stimulating stair use.

RESULTS

A total of 6771 choices between stairs and elevator were observed. There was a significant difference between stair use at baseline and during the poster intervention in both types of worksites. There was no worksite-by-intervention interaction, implying that the prompts were equally effective in both types of worksites. After removal of the posters stair use decreased significantly to a level that was not significantly different from baseline.

CONCLUSION

Stair use can be positively influenced in both blue- and white-collar workers by a short-term low-cost intervention using prompts on posters.

The Effects of Signage and the Physical Environment on Stair Usage

Background:

Physical activity (PA) is a health behavior that most Americans do not participate in at recommended levels.

Methods:

We sought to increase PA by use of motivational signs in selected buildings. Because physical environments are known to influence PA, the relationship of building characteristics and stair usage was also assessed. One pre- and two post-intervention observations were conducted.

Results:

The proportion of those using the stairs increased from baseline to the second data collection, (χ2 = 39.31, p < 0.01) and baseline to a final data collection (χ2 = 10.1, p < 0.01). Built environment factors, including steps to the next higher floor and the number of floors in the building were consistent predictors of stair use. With signs positioned, the visibility of the stairs while standing in front of elevators became a significant predictor of stair usage.

Conclusions:

Motivational signs and characteristics of built environments are associated with increased stair usage.

Spatial measures associated with stair use

PURPOSE

Although stair use in workplaces can provide an accessible means of integrating physical activity into work routines, there is little information available on how building design influences stair use.

DESIGN

This cross-sectional study assessed the relationship between stair use and the design and location of stairs.

SETTING

Ten three- or four-story academic buildings on two university campuses.

SAMPLE

The buildings contained a total of 38 stairs and 12 elevators.

MEASURES

Stair use was measured using infrared monitors. Eighteen environmental variables that operationalized the appeal, convenience, comfort, legibility, and safety of stairs were measured.

RESULTS

Regression analysis identified eight spatial variables associated with stair use: travel distances from stair to nearest entrance and the elevator, effective area or occupant load of each stair, accessibility of each stair, area of stair isovist (a graphic representation of the horizontal extent of a person's visual field from a specific point of reference within a building floor plan), number of turns required for travel from the stair to closest entrance, and the most integrated path (MIP). Three variables (effective area, area of stair isovist, and number of turns for travel from the MIP), explained 53 % of stair use in the 10 buildings. Most variables operationalizing the appeal, comfort, and safety of stairs were not statistically influential.

CONCLUSIONS

This study suggests that the spatial qualities that optimize the convenience and legibility of stairs may have the most influence on stair use in buildings.

Effects of a culturally sensitive sign on the use of stairs in African American commuters

OBJECTIVES

To examine the effectiveness of a culturally sensitive sign to encourage stair use among African American commuters.

METHODS

16,035 commuters were observed in their using either stairs or an adjacent escalator in a subway station. After baseline observation, a culturally sensitive sign to promote stair use was displayed beside the escalator/stairs. Demographic information and use of escalators/stairs were recorded.

RESULTS

Stair use increased from 15.8% to 21.5% with the sign. Caucasian commuters used the stairs 23.1% of the time at baseline, and increased to 28.3% with the sign. Among African Americans, stair use increased from 10.3% to 16.4% with the sign. African American women showed the greatest increases in stair use. Stair use remained elevated the week after the sign was removed in all commuters. Among African Americans, stair use returned to baseline within three weeks. Stair use increased significantly among both overweight and non-overweight Caucasians and African Americans.

CONCLUSION

Culturally sensitive interventions can promote physical activity among African Americans in an urban setting.

Longitudinal changes in prevalence of respiratory symptoms among Canadian grain elevator workers

OBJECTIVES

To determine longitudinal changes in the prevalence of chronic respiratory symptoms among Canadian grain workers.

DESIGN

Data on respiratory symptoms, smoking status, and pulmonary function were obtained approximately every 3 years (termed cycle) over 15 years beginning in 1978 from five regions of Canada.

PARTICIPANTS

The number of grain workers participating in each cycle were as follows: cycle 1 (n = 5,702); cycle 2 (n = 5,491); cycle 3 (n = 3,713); cycle 4 (n = 2,847); and cycle 5 (n = 3,079).

RESULTS

A procedure based on generalized estimating equations (PROC GENMOD; SAS Institute; Cary, NC) was used to fit marginal models to determine risk factors influencing the prevalence of chronic respiratory symptoms (wheeze, dyspnea, sputum, and cough). The prevalence (predicted probability based on the final model) of chronic respiratory symptoms had an increasing trend with increasing number of years in the grain industry from cycle 1 to cycle 3 (before dust control) for all three smoking categories (current smokers, ex-smokers, and nonsmokers). For cycle 4 and cycle 5 (after dust control), there was a reduction in the prevalence of these respiratory symptoms. For example, in cycle 1, the prevalence of chronic wheeze among current smoking grain workers increased from 12% (for those in the industry for < 5 years) to 44% (for those in the industry for > 35 years); in cycle 5, the prevalence of chronic wheeze among current smoking grain workers increased from 9% (for those in the industry for < 5 years) to 28% (for those in the industry for > 35 years). Similar trends were observed for ex-smokers and nonsmokers and for other chronic respiratory symptoms.

CONCLUSIONS

Our results indicate that grain dust control was effective in reducing the prevalence of chronic respiratory symptoms among grain workers in all smoking and exposure categories.

An uphill struggle: Effects of a point-of-choice stair climbing intervention in a non-English speaking population

BACKGROUND

Increases in lifestyle physical activity are a current public health target. Interventions that encourage pedestrians to choose the stairs rather than the escalator are uniformly successful in English speaking populations. Here we report the first test of a similar intervention in a non-English speaking sample, namely the Hong Kong Chinese.

METHODS

Travellers on the Mid-Levels escalator system in Hong Kong were encouraged to take the stairs for their health by a point-of-choice prompt with text in Chinese positioned at the junction between the stairs and the travelator. Gender, age, ethnic origin, and walking on the travelator were coded by observers. A 2 week intervention period followed 2 weeks of baseline monitoring with 57 801 choices coded. Specificity of the intervention was determined by contrasting effects in Asian and non-Asian travellers.

RESULTS

There was no effect of the intervention on stair climbing and baseline rates (0.4%) were much lower than previous studies in Western populations (5.4%). Nonetheless, a modest increase in walking up the travelator, confined to the Asian population (OR = 1.12), confirmed that the intervention materials could change behaviour.

CONCLUSIONS

It would be unwise to assume that lifestyle physical activity interventions have universal application. The contexts in which the behaviours occur, e.g. climate, may act as a barrier to successful behaviour change.

Mapping stairwell accessibility in Vancouver's downtown core

BACKGROUND

The increase in obesity is due in part to changes in the environment that affect behaviours such as physical activity. Stairwells in buildings present an opportunity to increase physical activity in the workplace. We characterized the stairwell accessibility in business buildings in the downtown core of Vancouver.

METHODS

Characteristics of the stairwells in business buildings with two or more floors were obtained. Stairwells were characterized based on their visibility from the main entrance, signage, presence of physical door, and interior lighting and space. Building completion year was obtained from the Vancouver City Hall.

RESULTS

A total of 138 buildings in the pre-designated area were eligible for characterization. Due to security concerns, only 123 were assessed. Of those assessed, 54% had stairwells visible from the main entrance, 33% had locked doors and only 18% had signs on the stairwell doors. Of the 83 stairwells that were accessible, 54% and 36% were considered brightly lit and spacious enough for two people, respectively. Only 11% of the buildings studied had accessible stairwells that met all of our accessibility criteria. More recently built buildings tended to have a higher proportion of locked stairwell doors; otherwise, building completion year was not associated with any of the accessibility criteria.

INTERPRETATION

Based on their environmental characteristics, very few buildings were set up in a way that encouraged stair use. For the work environment to be conducive to increased physical activity, building policy will need to consider the implications of design on activity patterns.

Lunar transportation scenarios utilising the Space Elevator

The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required delta v, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo.

The broken escalator phenomenon. Aftereffect of walking onto a moving platform

We investigated the physiological basis of the 'broken escalator phenomenon', namely the sensation that when walking onto an escalator which is stationary one experiences an odd sensation of imbalance, despite full awareness that the escalator is not going to move. The experimental moving surface was provided by a linear motor-powered sled, moving at 1.2 m/s. Sled velocity, trunk position, trunk angular velocity, EMG of the ankle flexors-extensors and foot-contact signals were recorded in 14 normal subjects. The experiments involved, initially, walking onto the stationary sled (condition Before). Then, subjects walked 20 times onto the moving sled (condition Moving), and it was noted that they increased their walking velocity from a baseline of 0.60 m/s to 0.90 m/s. After the moving trials, subjects were unequivocally warned that the platform would no longer move and asked to walk onto the stationary sled again (condition After). It was found that, despite this warning, subjects walked onto the stationary platform inappropriately fast (0.71 m/s), experienced a large overshoot of the trunk and displayed increased leg electromyographic (EMG) activity. Subjects were surprised by their own behaviour and subjectively reported that the 'broken escalator phenomenon', as experienced in urban life, felt similar to the experiment. By the second trial, most movement parameters had returned to baseline values. The findings represent a motor aftereffect of walking onto a moving platform that occurs despite full knowledge of the changing context. As such, it demonstrates dissociation between the declarative and procedural systems in the CNS. Since gait velocity was raised before foot-sled contact, the findings are at least partly explained by open-loop, predictive behaviour. A cautious strategy of limb stiffness was not responsible for the aftereffect, as revealed by no increase in muscle cocontraction. The observed aftereffect is unlike others previously reported in the literature, which occur only after prolonged continuous exposure to a sensory mismatch, large numbers of learning trials or unpredictable catch trials. The relative ease with which the aftereffect was induced suggests that locomotor adaptation may be more impervious to cognitive control than other types of motor learning.

The space elevator: a new tool for space studies

The objective has been to develop a viable scenario for the construction, deployment and operation of a space elevator using current or near future technology. This effort has been primarily a paper study with several experimental tests of specific systems. Computer simulations, engineering designs, literature studies and inclusion of existing programs have been utilized to produce a design for the first space elevator. The results from this effort illustrate a viable design using current and near-term technology for the construction of the first space elevator. The timeline for possible construction is within the coming decades and estimated costs are less than $10 B. The initial elevator would have a 5 ton/day capacity and operating costs near $100/lb for payloads going to any Earth orbit or traveling to the Moon, Mars, Venus or the asteroids. An operational space elevator would allow for larger and much longer-term biological space studies at selectable gravity levels. The high-capacity and low operational cost of this system would also allow for inexpensive searches for life throughout our solar system and the first tests of environmental engineering. This work is supported by a grant from the NASA Institute for Advanced Concepts (NIAC).

Dose escalation in locally advanced carcinoma of the prostate

Radiotherapeutic management of advanced prostate cancer is challenging. Several retrospective analyses showed a dose response for local tumor control before the availability of conformal radiation therapy. Attempts to escalate dose without the benefit of modern treatment planning was commonly fraught with high rates of bowel or bladder complications. The advent of image-guided or computed tomography-based treatment planning has allowed safe delivery of high-dose radiation therapy in men with prostate cancer with an acceptable rate of side effects and complications. Several prospective clinical trials have been conducted both at single institutions and in the cooperative group setting. Early evidence suggests that patients with high-risk factors such as advanced clinical stage, high initial prostate-specific antigen, or poorly differentiated tumors may benefit from high-dose 3-dimensional conformal radiation therapy with improved biochemical and local tumor control. A published randomized trial with conformal radiation therapy shows that a modest escalation of radiation dose leads to improved biochemical disease-free survival for a select group of patients. A confirmatory trial within the Radiation Therapy Oncology Group is underway to determine if dose escalation will improve overall survival in men without compromising quality of life.

Lymphocyte DNA damage in elevator manufacturing workers in Guangzhou, China

AIMS

To study the effect of smoking, passive smoking, alcohol drinking, and occupational exposure to low level of benzene on DNA strand breaks in elevator manufacturing workers in Guangzhou, China.

METHODS

Three hundred and fifty-nine workers (252 men and 107 women) of a modern elevator manufacturing factory, 205 were from production departments and 154 from managerial department. Information on the workers' health conditions, smoking, passive smoking, alcohol consumption and occupational exposure history was collected by personal interview. Lymphocyte DNA damage was measured by the Comet assay.

RESULTS

None of the women smoked and 20.6% of the men were daily smokers. In non-smokers, the prevalence of passive smoking at work was 25% for men and 11.2% for women, and at home, 37.8 and 48.6%, respectively. Smoking significantly increased tail moment (P<0.001). Daily smokers had the largest tail moment (geometric mean, 95% CI) (0.93 microm (0.81-0.94)), followed by occasional smokers (0.76 microm (0.59-0.95)), ex-smokers (0.70 microm (0.58-0.85)), and never smokers (0.56 microm (0.53-0.60)). Tail moment increased significantly with daily tobacco consumption (cigarettes per day) (r=0.26, P<0.001) after adjusting for age, gender, occupational exposure, passive smoking, and drinking. Analysis of covariance (ANCOVA) showed that smoking (P<0.001), passive smoking at home (P=0.026), occupational exposure (P<0.001), male gender (P<0.001), and age (P=0.001) had independent effects on tail moment, whereas passive smoking at work and alcohol drinking had no significant effect.

CONCLUSIONS

Smoking, passive smoking at home, male gender, age and occupational exposure independently increased lymphocyte DNA strand breaks. The presence of excess DNA damage under low level of occupational exposure to benzene or other solvents suggest that the current allowance concentrations may not be safe to prevent genotoxicity.