Brief Standing Desk Intervention to Reduce Sedentary Behavior at a Physical Activity Conference in 2016

Abstract

Objectives. To examine the impact of environmental restructuring on attendees at a physical activity conference when provided with standing tables and given point-of-decision prompts (PODPs; e.g., health messages).

Methods. This randomized controlled trial took place at the Health-Enhancing Physical Activity Europe 2016 conference in Belfast, United Kingdom, September 2016. We randomly allocated 14 oral sessions to either the intervention group (standing tables + PODPs; n = 7) or the control group (PODPs only; n = 7). Conference volunteers discreetly recorded the number of attendees standing and sitting and estimated the number of women and attendees aged 40 years or older.

Results. There was a significant difference (P = .04) in the proportion of attendees standing during the intervention (mean = 16.8%; SD = 9.5%) than during control sessions (mean = 6.0%; SD = 5.8%). There was no differential response between gender and age groups in the proportion standing during intervention sessions (P > .05).

Conclusions. Providing standing tables may be a feasible and effective strategy to reduce sitting at physical activity conferences.

Uninterrupted sedentary behaviors, such as sitting while watching television and working at a desk, have been linked to negative health outcomes in adults.^1–3 Interrupting prolonged sedentary behavior is known to have beneficial health effects.⁴ One method of positively altering behaviors is to provide point-of-decision prompts (PODPs). PODPs are informative messages used to motivate individuals and are inexpensive. They have been successfully used to increase stair use⁵ and walking in parks⁶ and decrease sedentary time in office environments.⁷

Workplace meetings and conferences, in particular, encourage long periods of sitting. A recent study demonstrated that a simple message displayed during conference sessions resulted in a higher proportion of attendees standing.⁸ Another strategy to reduce sedentary time is restructuring the environment.⁹ For example, standing desks have been successfully used in schools and workplaces.^10,11 However, to our knowledge, no previous studies have assessed whether combining PODPs with environmental aids (e.g., standing tables) decreases or interrupts sedentary behavior during meetings and conferences.

We examined the impact of environmental restructuring by providing standing tables combined with PODPs and observing the proportion of attendees at an academic conference who stood. We hypothesized that, in rooms with PODPs being displayed, a higher proportion of conference attendees would stand if the rooms contained standing tables than if they did not.

METHODS

We performed a randomized controlled trial (Figure A, available as a supplement to the online version of this article at http://www.ajph.org) at the Health-Enhancing Physical Activity Europe conference in September 2016. There were more than 300 delegates from 25 countries at this conference. We randomly allocated 14 oral sessions (lasting 45–90 minutes each) to the intervention (standing tables + PODPs; n = 7) or control (PODPs only; n = 7) group using a computerized random number generator (Figure B, available as a supplement to the online version of this article at http://www.ajph.org). Sessions took place between 11:00 am and 4:45 pm and consisted of 4 to 8 presentations lasting 10 minutes on themes related to physical activity. The intervention and control sessions ran in parallel. In proportion to the room sizes allocated to the intervention group, we placed 6 to 12 standing tables at the back of each room (Figure C, available as a supplement to the online version of this article at http://www.ajph.org). Control rooms had no standing tables although we left space at the back to allow standing. In total, 5 presentation rooms were used 2 to 3 times per day across 2 days (Figure 1). Before each session, a PODP to encourage standing was announced or visually displayed (Figure D, available as a supplement to the online version of this article at http://www.ajph.org). We gave 12 observers (Table A, available as a supplement to the online version of this article at http://www.ajph.org) training and written instructions on data collection. After the first minute of each presentation, 1 observer discreetly positioned him- or herself so that he or she could survey the whole room and record the number of attendees standing and sitting. The observer, using a standardized form, estimated the number of women standing and sitting and the number of attendees aged 40 years or older standing and sitting.

FIGURE 1—

One of the Rooms With Standing Tables Being Used at the Health-Enhancing Physical Activity Europe Conference: Belfast, Northern Ireland, September 2016

Source. Photograph by Andrew Towe (Parkway Photography Limited).

Inclusion and Exclusion Criteria

We observed all individuals except those already aware of the study (coauthors, volunteer observers, and chairpersons of selected oral sessions, who were told the observations were occurring so that they would not draw attention to them), wheelchair users, and others with obvious mobility impairments.

Statistical Analysis

We calculated descriptive statistics (mean ± SD) for the individuals who stood during oral sessions in the intervention and control groups as well as estimated gender and age. We compared the mean of the recorded proportion standing (determined every 10 minutes) within each session between the intervention and control groups using an independent samples t test. This method is recommended¹² to account for clustering of values, such as repeated measurement of the proportion standing in each session. We tested differences in women, men, those younger than 40 years, and those aged 40 years and older in the intervention versus control groups. We also tested differences between the proportions of women versus men standing and the proportions of those younger than 40 years versus those aged 40 years and older in the intervention group only. We chose 2 oral sessions for quality checking by a second observer. We used intraclass correlation coefficients to assess interrater reliability, with values of 0.7 or higher being acceptable. We used SPSS version 22 (IBM, Somers, NY) to perform analyses. We set statistical significance at a P level of less than .05.

RESULTS

One control session failed to display a PODP, so we did not count in that session; therefore, we included 13 sessions (Figure B). Mean observations were 250 attendees in intervention sessions and 236 in control sessions (Table 1). There was a significant difference (P = .04) in the proportion of attendees standing in the intervention (16.8% ± 9.5%) compared with the control (6.0% ± 5.8%) sessions. A higher proportion of women stood in the intervention sessions (19.1% ± 10.0% vs 7.1% ± 6.4%; P = .03). A significantly higher proportion of both those younger than 40 years (15.7% ± 9.1% vs 5.0% ± 4.5%; P = .02) and aged 40 years and older (21.4% ± 9.8% vs 8.1% ± 8.6%; P = .03) stood during the intervention sessions.

TABLE 1—

Proportions of Attendees Who Stood During Intervention and Control Sessions Subdivided Into Attendee Characteristics: Health-Enhancing Physical Activity Europe Conference: Belfast, Northern Ireland, September 2016

	Intervention Sessions (n = 7)			Control Sessions (n = 6)
Attendee Characteristics	Mean Total No. From the Observer Countsa	Mean No. Standing From the Observer Countsa	Proportion Standing,b %	Mean Total No. From the Observer Countsa	Mean No. Standing From the Observer Countsa	Proportion Standing,b %	Intervention vs Control Sessions for Proportion Standing, P
All	250	45	16.8	236	18	6.0	.04
Gender
Female	144	31	19.1	138	12	7.1	.03
Male	107	14	14.7	98	9	4.4	.08
Age, y
< 40	167	27	15.7	140	9	5.0	.02
≥ 40	83	18	21.4c	95	9	8.1	.03

^aMean total and standing values displayed are averaged from the proportions from each oral session and rounded to the nearest whole number.

^bProportion standing values displayed are averaged from the proportions from each oral session and rounded to 1 decimal place.

^cn = 6 (no attendees aged ≥ 40 years in 1 session).

In the intervention group, there was no significant difference between the proportion of women standing and the proportion of men standing (P = .46). There was also no difference during intervention sessions between the proportion of attendees younger than 40 years standing compared with the proportion of attendees aged 40 years or older standing (P = .30). Interrater reliability for 2 oral sessions that we selected for quality checking had intraclass correlation coefficient values higher than 0.7, apart from the number of total attendees aged 40 years or older (Table B, available as a supplement to the online version of this article at http://www.ajph.org).

DISCUSSION

Providing standing tables in addition to PODPs significantly increased standing during intervention versus control sessions. This finding was mirrored across gender and age groupings—suggesting that this intervention had an equitable effect. To our knowledge, this is the first study investigating the effects of restructuring the environment with standing tables at a conference. These findings are important because sedentary behavior has emerged as a public health concern.^1–4 We placed standing tables at the entrance to the oral sessions, which may have acted as an active environmental nudge to encourage standing rather than sitting. We consider adding standing tables to a conference room a feasible way to influence behavior, because no extra time or space was required and implementation costs were minimal.

A surprising finding was the low proportion of attendees who stood during control sessions. This is despite this audience being aware of the benefits of interrupting prolonged sitting, as well as PODPs being displayed during sessions and having sufficient standing space. This proportion (6.0% vs 16.9%) is lower than that of another study, which used only PODPs at a conference.⁸ This demonstrates that additional restructuring of the physical environment, such as reducing the number of chairs and increasing the number of standing tables, may be needed to further encourage standing. Interestingly, the lack of standing tables in some rooms was included in the attendees’ feedback received by the conference organizers, showing that infrastructure may be a key barrier to behavior change.

Limitations and Strengths

We estimated gender and age grouping, which reduces the strength of these findings. Adjustments in the analysis for estimated gender and age along with room sizes and layouts were not possible. Attendees were able to move between oral sessions, affecting the independence of observations between sessions. Future research at larger conferences holding numerous simultaneous sessions would address this issue. Considering the focus of the conference, audiences were likely to know about the benefits of reducing sedentary behavior, although only a small proportion stood during control sessions. Strengths of this study include a randomized controlled design, completing quality checks, and recording attendee characteristics (i.e., gender and age).

Public Health Implications

We demonstrated that providing standing tables is a feasible and effective strategy to help reduce sitting time and promote standing at conferences. Organizers of future conferences or workplace meetings should consider providing standing tables for attendees in addition to PODPs that encourage standing. Future research could explore the impact of introducing standing tables in other contexts, such as workplace and public meetings and events.