Desk Position Research Articles

Smart Software Can Increase Sit-Stand Desk Transitions During Active Computer Use.

The objective use of table top adjustable sit–stand desks has yet to be determined, due to the lack of an effective digital evaluation method. The objective of this study was to evaluate the impact of computer prompt software on table top sit–stand desks to determine if there was a difference in the frequency of desk position changes. This five month, pre-post pilot study on 47 university staff members used a novel USB accelerometer sensor and computer software reminders to continuously record and prompt increases in desk usage to promote physical activity at the workstation. During the baseline phase (3 months), desk usage data were continuously recorded for all workers. Following the baseline, the results from a two-month intervention of personalized computer reminders doubled the number of desk position changes per work day from 1 desk position change every 2 work days to 1 change every work day. Furthermore, those who changed desk positions once or twice a day increased from 4% to 36% from baseline to intervention. Overall, the intervention was encouraging, but longer intervention studies are warranted to determine if the desk usage behavior change can be improved and sustained for years and whether that change results in health gains.

Environmental factors in school classrooms: How they influence visual task demand on children.

BackgroundThe key visual factors in a classroom environment include the legibility, angle subtended at the eye, illumination, contrast, and colour of the visual task. The study evaluated the visual environmental factors in the school classrooms.Materials and methodsThe distance Visual Acuity (VA) demand was evaluated based on the size of visual task i.e. the smallest size of chalkboard writing and its viewing distance. The environmental factors which can have an effect on the visibility in classrooms such as illuminance on the chalkboard and at student’s desk, chalkboard contrast, light sources and the student’s perception of their classroom visual environment were measured. To quantify the distance VA demand and to compare with a standard high contrast VA chart measure, a validation of the measurements was performed by chalkboard simulation experiment. The “acuity reserve” to be included to the measured distance VA demand was evaluated.ResultsWe included twenty-nine classrooms of eight schools. The median distance VA threshold demand was 0.28 logMAR(0.25,0.45). The median illuminance on front desk position and chalkboard contrast was 130 lux(92,208) and 40(36,50) respectively with 62% classrooms having low illumination (<150lux). The acuity reserve evaluated to be included to the distance VA demand was 0.13logMAR and 0.29 logMAR in classrooms with optimal and low chalkboard illumination respectively which was based on the results of the simulation experiment. The median distance VA demand including the acuity reserve was 0.09 logMAR(-0.03,0.23) [Snellen Equivalent: 20/25(20/19,20/34)].ConclusionThe study findings highlight the increased visual task demand in school classrooms and the need for appropriate seating arrangements in classrooms based on the visual acuity of children. The study emphasises regular audit of the classroom environment along with the school eye screening.

Sit-Stand Desk Software Can Now Monitor and Prompt Office Workers to Change Health Behaviors.

Objective:To determine the effectiveness of a computer-based intervention designed to increase sit-stand desk usage and help reverse workplace physical inactivity.Background:Sit-stand desks have been successful in reducing workplace sedentary behavior, but the challenge remains for an effective method to increase the usage in order to experience the health and productivity benefits.Method:Data collection (1-year field study with 194 workers) used a novel method of computer software that continuously recorded objective electric sit-stand desk usage, while taking into account the time a worker spends away from their desk (breaks, meetings). During the baseline period, all workers’ desk usage was recorded by the software, and the intervention period consisted of software reminders and real-time feedback to all workers to change desk positions. Pooled means were calculated to determine desk usage patterns, and effect sizes and pairwise mean differences were analyzed to test for intervention significance.Results:The intervention doubled desk usage by increasing ~1 change to ~2 changes per work day. There was a 76% reduction in workers who never used the sit-stand function of the desk. Medium to large effect sizes from the intervention were observed in all three primary outcome measures (desk in sitting/standing position and desk position changes per work day).Conclusion:These findings demonstrate an effective intervention that increased postural transitioning and interrupted prolonged inactivity while remaining at the workstation.Application:The methods and results in this research study show that we can quantify an increase in desk usage and collect aggregate data continuously.

Usage of Sit-Stand Workstations and Associations Between Work and Nonwork Sitting Time: An Observational Study.

No studies have objectively measured habitual usage of sit-stand workstations. Eighteen full-time office workers participated (47.9 ± 9.2 years, 61% female). Sitting time was objectively measured (activPAL, 24 h/7 days), and time at desk, desk position, and perceptions of desk use were self-reported. Participants sat for 39% of their daily workstation time, and changed workstation position twice daily. The most common reasons for standing included back pain (44%) and tiredness (22%). The majority of participants received no workstation occupational health (72%) or educational (61%) information. Workstation standing time had a significant moderate correlation with total daily standing time (P = 0.02). Office workers with sit-stand workstations rarely change desk position, and there is no relationship between the time spent sitting at the workstation, and total daily sitting time. Education about the workstations was limited.

A Quantitative Evaluation of Electric Sit-Stand Desk Usage: 3-Month In-Situ Workplace Study

OCCUPATIONAL APPLICATIONSSit-stand desk interventions are deployed to reduce sedentary time and improve ergonomic adjustability in modern workplaces, with ultimate goals of improving health and productivity. Sit-stand desks, however, require workers to take an active role in changing the desk position, and usage compliance of the sit-stand function has been a challenge. This study used computer software to objectively record continuous data on electric sit-stand desk usage during computer use, to understand current desk usage behaviors in a large office environment involving ∼300 workers for 3 months. We found that workers completed roughly one desk position change per work day, and one-fourth of the workers always had the desk in a seated position (during computer use). The methods used here demonstrate a novel approach to record sit-stand desk usage continuously during active computer use.

Examining Occupancy and Architectural Aspects Affecting Manual Lighting Control Behaviour in Offices Based on a User Survey

Further understanding the building occupantsТ needs and behaviors can reduce lighting energy consumption. This research explores how the occupancy and interior architectural aspects become effective in manual lighting control in offices. It involves a multiple sectioned questionnaire focusing on the possible architectural factors such as the desk position, the surface colors, the distance to window, the distance between desk and lighting switch, and inquiring participantsТ manual lighting control behavior through the photographs of modified interior layouts, surface colors and time intervals. Statistical methods are used to determine the significant aspects, which may reduce the use of lighting control. Interior layout, distance to window, time of the day, and number of occupants in the offices are the most significant contributions to the manual lighting control behavior. To pay attention in these contributions, it would be possible to reduce the use of electricity for lighting while user satisfaction increases.

Do school classrooms meet the visual requirements of children and recommended vision standards?

BackgroundVisual demands of school children tend to vary with diverse classroom environments. The study aimed to evaluate the distance and near Visual Acuity (VA) demand in Indian school classrooms and their comparison with the recommended vision standards.Materials and methodsThe distance and near VA demands were assessed in 33 classrooms (grades 4 to 12) of eight schools. The VA threshold demand relied on the smallest size of distance and near visual task material and viewing distance. The logMAR equivalents of minimum VA demand at specific seating positions (desk) and among different grades were evaluated. The near threshold was converted into actual near VA demand by including the acuity reserve. The existing dimensions of chalkboard and classroom, gross area in a classroom per student and class size in all the measured classrooms were compared to the government recommended standards.ResultsIn 33 classrooms assessed (35±10 students per room), the average distance and near logMAR VA threshold demand was 0.31±0.17 and 0.44±0.14 respectively. The mean distance VA demand (minimum) in front desk position was 0.56±0.18 logMAR. Increased distance threshold demand (logMAR range -0.06, 0.19) was noted in 7 classrooms (21%). The mean VA demand in grades 4 to 8 and grades 9 to 12 was 0.35±0.16 and 0.24±0.16 logMAR respectively and the difference was not statistically significant (p = 0.055). The distance from board to front desk was greater than the recommended standard of 2.2m in 27 classrooms (82%). The other measured parameters were noted to be different from the proposed standards in majority of the classrooms.ConclusionThe study suggests the inclusion of task demand assessment in school vision screening protocol to provide relevant guidance to school authorities. These findings can serve as evidence to accommodate children with mild to moderate visual impairment in the regular classrooms.

Usage Position and Virtual Keyboard Design Affect Upper-Body Kinematics, Discomfort, and Usability during Prolonged Tablet Typing.

PurposeThe increase in tablet usage allows people to perform computer work in non-traditional office environments. The aim of this study was to assess the effects of changes in tablet keyboard design on postures of the upper extremities and neck, discomfort, and usability under different usage positions during prolonged touch-typing.MethodsEighteen healthy participants familiar with touch-screen devices were randomized into three usage positions (desk, lap, and bed) and completed six, 60-minute typing sessions using three virtual keyboard designs (standard, wide, split). Electrogoniometers continuously measured the postures of the wrists, elbow, and neck. Body discomfort and system usability were evaluated by questionnaires before and immediately after each typing session.ResultsSeparate linear mixed effects models on various postural measures and subjective ratings are conducted with usage position as the between-subject factors, keyboard design and typing duration as the with-in subject factors were conducted. Using the tablet in bed led to more extended wrists but a more natural elbow flexion than the desk position. The angled split virtual keyboard significantly reduced the extent of wrist ulnar deviation than the keyboard with either standard or wide design. However, little difference was observed across the usage position and keyboard design. When the postural data were compared between the middle and end of typing sessions, the wrists, elbow, and neck all exhibited a substantially increased range of joint movements (13% to 38%). The discomfort rating also increased significantly over time in every upper body region investigated. Additionally, the split keyboard design received a higher usability rating in the bed position, whereas participants had more satisfactory experience while using the wide keyboard in the traditional desk setting.ConclusionsProlonged use of tablets in non-traditional office environments may result in awkward postures in the upper body that may expose users to greater risks of developing musculoskeletal symptoms. Adequate virtual keyboard designs show the potential to alleviate some postural effects and improve the user experience without changing the tablet form factors.

Daylighting and visual performance: evaluation of classroom design issues in the UAE

The study focuses on analysis of visual performance and quality issues in classrooms located in the United Arab Emirates (UAE). The methodology depended on data collection and analysis of design information obtained from architectural drawings of standard schools, design compliance documents set by the relevant governmental bodies, and site visits and photography. It analyzed several important design issues that have significant impact on visual quality, including space size and depth to height ratio, windows orientation, lighting direction and desk position. It used simulation to investigate potential visual problems during critical times and view angles. Several problems concerning contrasting luminance levels in the field of view were identified and described. Mitigation of the problems using recommended daylighting systems was discussed based on the UAE climate. Copyright The Author 2010. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org, Oxford University Press.

The impact of arm position and pulse pressure on the validation of a wrist-cuff blood pressure measurement device in a high risk population

Despite the increasing popularity of blood pressure (BP) wrist monitors for self-BP measurement at home, device validation and the effect of arm position remains an issue. This study focused on the validation of the Omron HEM-609 wrist BP device, including an evaluation of the impact of arm position and pulse pressure on BP measurement validation. Fifty patients at high risk for cardiovascular disease were selected (age 65 +/- 10 years). Each patient had two measurements with a mercury sphygmomanometer and three measurements with the wrist BP device (wrist at the heart level while the horizontal arm supported [HORIZONTAL], hand supported on the opposite shoulder [SHOULDER], and elbow placed on a desk [DESK]), in random order. The achieved systolic BP (SBP) and diastolic BP (DBP) wrist-cuff readings were compared to the mercury device and the frequencies of the readings within 5, 10, and 15 mmHg of the gold standard were computed and compared with the British Hypertension Society (BHS) and Association for the Advancement of Medical Instrumentation (AAMI) protocols. The results showed while SBP readings with HORIZONTAL and SHOULDER positions were significantly different from the mercury device (mean difference = 7.1 and 13.3 mmHg, respectively; P < 0.05), the DESK position created the closest reading to mercury (mean difference = 3.8, P > 0.1). Approximately 71% of SBP readings with the DESK position were within +/-10 mmHg, whereas it was 62.5% and 34% for HORIZONTAL and SHOULDER positions, respectively. Wrist DBP attained category D with BHS criteria with all three arm positions. Bland-Altman plots illustrated that the wrist monitor systematically underestimated SBP and DBP values. However a reading adjustment of 5 and 10 mmHg for SBP and DBP (DESK position) resulted in improvement with 75% and 77% of the readings being within 10 mmHg (grade B), respectively. AAMI criteria were not fulfilled due to heterogeneity. The findings also showed that the mismatch between the mercury and wrist-cuff systolic BP readings was directly associated with pulse pressure. In conclusion the DESK position produces the most accurate readings when compared to the mercury device. Although wrist BP measurement may underestimate BP measured compared to a mercury device, an adjustment by 5 and 10 mmHg for SBP and DBP, respectively, creates a valid result with the DESK position. Nevertheless, considering the observed variations and the possible impact of arterial stiffness, individual clinical validation is recommended.

Desk position, interviewee anxiety, and interviewer credibility: An example of cognitive balance in a dyad.

Desk position, interviewee anxiety, and interviewer credibility: An example of cognitive balance in a dyad.