Clinical trial NCT05970588: Standing Desk Converter & Habitual Posture
Official title: Impact of a Standing Desk Converter Intervention on Habitual Posture, Cognition, and Cardiovascular Health
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Sedentary Time
Cognitive Function
Blood Pressure Regulation
Keywords: Standing Time
Occupational Health
Stroop Task
Carotid Intima-Media Thickness
Head-Up Tilt
Objectively Measured Activity
Lead sponsor: Dalhousie University
Sponsor class: OTHER
First posted: 2023-08-01
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: A block randomization strategy will be implemented to ensure equal allocations to intervention/control groups in groups of 6 (3 per group). Even and odd numerals will represent designation to the Intervention and Control groups, respectively. For example, if the first 3 participants are randomized to the control group, the next 3 will be allocated to the intervention group. To ensure all control participants will be offered the intervention after their control period, the first 3 participants for the final block of 6 (block 7) will be randomized to the control group first. Randomization will occur after Visit 1 assessments are complete.
Primary purpose: OTHER

Brief summary: This project will determine the short-term impact of a standing desk converter on: 1) objectively measured physical activity and posture levels, and 2) brain (cognition) and heart (blood pressure regulation) function. The main outcome is habitual activity patterns, assessed by the thigh-worn inclinometer (activPAL). All participants will be equipped with an activPAL and have their cardiovascular and cognitive function assessed at baseline and 4 weeks. Participants in the intervention group will use a standing desk converter for 4 weeks, while the wait-list control group will be encouraged to maintain their regular activity patterns. Researchers will compare the intervention and control groups to see if using the standing desk converter will increase standing time and lower sedentary time, improve cognition, and improve blood pressure regulation.

Detailed description: Background: Too much sedentary time (time spent sitting, reclining, or lying) leads to health problems such as cognitive impairments or cardiovascular disease. A lot of sedentary time is accumulated while working at a desk (e.g., computer work, studying, etc.). Standing desk interventions have provided mixed support as to whether they can reduce habitual sedentary time, with the need for more controlled interventional studies. It remains to be determined if a simple standing desk converter (i.e., a height-adjusted desk that can be set on top of a traditional sitting desk) increases standing time (i.e., not sedentary) and/or decreases sedentary time. Worse cognitive health and higher blood pressure are linked to a greater risk of chronic conditions such as dementia and cardiovascular disease, respectively. More physical activity improves cognition and blood pressure regulation, but whether standing more also translates to these brain and heart improvements is unclear.

Main Objective: The goals of this project are to determine the impact of a standing desk converter on: 1) objectively measured physical activity and posture levels, and 2) brain (cognition) and heart (blood pressure regulation) function. It is expected that using the standing desk converter will increase standing time and lower sedentary time, improve cognition, and improve blood pressure regulation.

Methodology: For the proposed project, we will assess free-living posture, cognition, and blood pressure regulation before and after 4-weeks of either using a standing desk converter (intervention) or a wait-list control. The study population targets adults who use a traditional seated desk for a minimum of 20 hours per week and do not already use a standing desk. Free-living activity will be assessed using activity monitors (activPALs) worn for 7-days before and after either the control period or intervention. Cognition will be assessed using a computerized Stroop task that records accuracy and reaction times to selecting the colour of the word or the word itself (e.g., word BLUE written in red font). Progressively more challenging Stroop conditions will be used to assess different aspects of cognition. During the Stroop, cerebral oxygenation will be determined using near-infrared spectroscopy. Beat-by-beat blood pressure (via finger cuff), heart rate (via electrocardiogram), and internal carotid artery size and red blood cell velocity (via ultrasound) will be measured while lying down and in response to 20 minutes of 60-degree passive head-up tilt that tests blood pressure regulation. The proposed study will yield new knowledge as it relates to real-life posture interventions that promote healthier movement and investigates whether standing converters lead to improvements in brain and heart health.

Significance: The proposed study will yield new knowledge as it relates to real-life posture interventions that promote healthier movement and investigates whether standing converters lead to improvements in brain and heart health.

Eligibility criteria: Inclusion Criteria:

* 18 years of age or older
* Are normotensive, cognitively healthy, and do not have a history of fainting while standing
* Are able to stand for 10 min without assistance (e.g., require a walker, person assistance)
* Are not allergic to clear medical adhesive (TegadermTM, 3M) used to secure the activPAL activity monitors
* Use a seated desk at least 20 hours/week in the last month and do not use a standing or active desk already
* Females who are not pregnant, breastfeeding or planning on becoming pregnant prior to entry into the study

Exclusion Criteria:

* Younger than 18 years old
* Hypertension (resting systolic pressure \>139 mmHg and/or diastolic pressure \>89 mmHg)
* Have a diagnosed cognitive impairment
* Have a history of orthostatic hypotension/intolerance and/or fainting while standing
* Cannot stand for at least 10 min without assistance (e.g., require a walker, person assistance)
* Have a known allergy to the clear medical adhesive (TegadermTM, 3M)
* Use a seated desk less than 20 hours/week, use a standing or active desk already, or use a desk for more than 20 hours/week but not in the last month
* Females who are pregnant, breastfeeding or planning on becoming pregnant prior to entry into the study

Primary outcomes:
measure: ActivPAL monitors
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
Secondary outcomes:
measure: Cognition
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
measure: Brain Activation: Functional Near Infrared Spectroscopy
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
measure: Electrocardiography
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
measure: Continuous Finger Blood Pressure Recording (Finapres Medical Systems)
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
measure: Upper Arm Blood Pressure Measurements
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
measure: Carotid Artery Structure
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
measure: Carotid Artery Function
timeFrame: Change from baseline (week 0) activity to post intervention (week 4).
Other outcomes:
Locations:
city: Halifax
country: Canada
facility: Dalhousie University
state: Nova Scotia
Study officials:
affiliation: Department of Medicine and Department of Physiotherapy, Dalhousie University
name: Myles W O'Brien, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Dorey TW, O'Brien MW, Robinson SA, Kimmerly DS. Knee-high compression socks minimize head-up tilt-induced cerebral and cardiovascular responses following dynamic exercise. Scand J Med Sci Sports. 2018 Jul;28(7):1766-1774. doi: 10.1111/sms.13084. Epub 2018 Apr 16.
citation: Neuhaus M, Eakin EG, Straker L, Owen N, Dunstan DW, Reid N, Healy GN. Reducing occupational sedentary time: a systematic review and meta-analysis of evidence on activity-permissive workstations. Obes Rev. 2014 Oct;15(10):822-38. doi: 10.1111/obr.12201. Epub 2014 Jul 11.
citation: O'Brien MW, Daley WS, Schwartz BD, Shivgulam ME, Wu Y, Kimmerly DS, Frayne RJ. Characterization of Detailed Sedentary Postures Using a Tri-Monitor ActivPAL Configuration in Free-Living Conditions. Sensors (Basel). 2023 Jan 4;23(2):587. doi: 10.3390/s23020587.
citation: Petterson, JL, Mekari, S, O'Brien, MW. An open-source Stroop task program that incorporates a switching condition to determine executive function. Software Impacts. 2022 Jul 7 13, 100361. doi: 10.1016/j.simpa.2022.100361
citation: de Rezende LF, Rodrigues Lopes M, Rey-Lopez JP, Matsudo VK, Luiz Odo C. Sedentary behavior and health outcomes: an overview of systematic reviews. PLoS One. 2014 Aug 21;9(8):e105620. doi: 10.1371/journal.pone.0105620. eCollection 2014.
citation: Thorp AA, Healy GN, Winkler E, Clark BK, Gardiner PA, Owen N, Dunstan DW. Prolonged sedentary time and physical activity in workplace and non-work contexts: a cross-sectional study of office, customer service and call centre employees. Int J Behav Nutr Phys Act. 2012 Oct 26;9:128. doi: 10.1186/1479-5868-9-128.
citation: O'Brien MW, Kimmerly DS, Mekari S. Greater habitual moderate-to-vigorous physical activity is associated with better executive function and higher prefrontal oxygenation in older adults. Geroscience. 2021 Dec;43(6):2707-2718. doi: 10.1007/s11357-021-00391-5. Epub 2021 Jun 3.
citation: De Vries J, Michielsen HJ, Van Heck GL. Assessment of fatigue among working people: a comparison of six questionnaires. Occup Environ Med. 2003 Jun;60 Suppl 1(Suppl 1):i10-5. doi: 10.1136/oem.60.suppl_1.i10.
citation: Hatoum T, Sheldon R. A practical approach to investigation of syncope. Can J Cardiol. 2014 Jun;30(6):671-4. doi: 10.1016/j.cjca.2014.03.043. Epub 2014 Apr 3.
citation: Petersen ME, Williams TR, Gordon C, Chamberlain-Webber R, Sutton R. The normal response to prolonged passive head up tilt testing. Heart. 2000 Nov;84(5):509-14. doi: 10.1136/heart.84.5.509.
citation: Bantoft C, Summers MJ, Tranent PJ, Palmer MA, Cooley PD, Pedersen SJ. Effect of Standing or Walking at a Workstation on Cognitive Function: A Randomized Counterbalanced Trial. Hum Factors. 2016 Feb;58(1):140-9. doi: 10.1177/0018720815605446. Epub 2015 Sep 24.
citation: E F Graves L, C Murphy R, Shepherd SO, Cabot J, Hopkins ND. Evaluation of sit-stand workstations in an office setting: a randomised controlled trial. BMC Public Health. 2015 Nov 19;15:1145. doi: 10.1186/s12889-015-2469-8.
citation: Ma J, Ma D, Li Z, Kim H. Effects of a Workplace Sit-Stand Desk Intervention on Health and Productivity. Int J Environ Res Public Health. 2021 Nov 4;18(21):11604. doi: 10.3390/ijerph182111604.