Printer Friendly

Process evaluation of an intervention to interrupt sedentary time in diabetics.


Type II Diabetes (T2D) is a growing worldwide concern and a leading cause of cardiovascular disease and associated morbidities (World Health Organization, 2014). Physical activity (PA) has been identified as a protective factor for both the prevention and management of T2D (LaMonte, Blair, & Church, 2005). Community-based interventions are needed to provide at-risk populations with effective treatments to prevent or manage T2D. However, to enhance adherence such interventions should be convenient and simple to follow. Walking is one of the most common forms of activity and has been shown to improve hemoglobin Ale levels and insulin sensitivity with and without clinical supervision (Qiu et al., 2014; Motahari-Tabari, Ahmad Shirvani, Shirzad-E-Ahoodashty, Yousefi-Abdolmaleki, & Teimourzadeh, 2014).

Walking programs of varying lengths (i.e., 8 weeks vs. 12 weeks) have been administered in a variety of settings with varying degrees of success. A recent review demonstrates that pedometer-based walking programs have been shown to have overall mixed results on hemoglobin Ale in adults with T2D (Funk & Taylor, 2013). In order to better understand why some programs work better than others, studies should define the specific components of the intervention and document the fidelity of implementation before drawing conclusions about the efficacy of an intervention.

While walking has been shown as an effective means to increase PA, which in turn has the potential to help manage conditions such as T2D, walking programs may be enhanced when additional behavioral strategies are included such as those that interrupt sedentary time with short sessions of moderate intensity PA. Sedentary time refers to any waking behavior with an energy expenditure of [less than or equal to] 1.5 METS while in a sitting or reclining posture (Sedentary Behaviour Research Network, 2012). While there are well established recommendations for minimum levels of PA to enhance health, there are no recommendations for maximal amounts of sitting time that have been associated with detrimental health outcomes. Additionally, there is no recommendation for a number, intensity, or duration of interruptions to sedentary time. Recent research has tested the feasibility of interrupting sedentary time with short periods of activity in older adults (Gardiner, Eakin, Healy, & Owen, 2011). This strategy has also been studied in other populations and has been associated with health benefits such as insulin resistance, waist circumference, and triglycerides. These results were independent of those associated with total sedentary time or moderate to vigorous PA (Healy et al., 2008; Cooper et al., 2012). It should be noted that this research was cross-sectional or involved short-term interventions (< 1 week). Research documenting the effects of interrupting sedentary time for longer periods of time is greatly needed.

The purpose of this article was to describe the process evaluation of two intervention strategies among university faculty and staff with T2D. The first strategy was designed to interrupt sedentary time using short breaks of moderate walking and the other strategy used a standard walking program. Information from this article will provide researchers and practitioners with practical recommendations for future PA programs designed to use short breaks of moderate walking to interrupt sedentary time of people with T2D.

Design and Implementation

After receiving approval from the university's Institutional Review Board, a mass email was distributed to recruit male and female faculty and staff members at a university of 29,000 students in the central U.S. Participants were screened over the telephone to ensure they met the study's qualifications before attending a preliminary data collection session. Inclusion criteria included: age range between 40-64 years, clinically diagnosed with T2D ([greater than or equal to] 3 months post-diagnosis), inactive (<150 minutes of moderate intensity PA/week), and no impairment to walking. Eligible individuals were met in person and asked to read a description of the study before consenting to participate. Each participant was also required to obtain approval from their primary diabetes physician to participate in this study. Upon approval, participants were sent hyperlinks to nine online surveys to complete before beginning the walking program. Participants also were assigned an accelerometer (Actigraph GT1M) and pedometer (Yamax SW200) and were asked to wear them for seven consecutive days in order to measure PA, sedentary time, and breaks in sedentary time. These devices were collected when participants attended a final pre-intervention visit at which anthropometric and clinical outcomes were measured.

Following preliminary testing, participants were randomly assigned to one of the two, twelve-week intervention groups; the breaks group and the walking group. The breaks group was asked to interrupt each hour of sedentary time with small bouts of moderate intensity PA lasting at least two minutes. A fully compliant participant would never be sitting for more than an hour on a continuous basis without a two minute interruption of moderate PA (break). During each break, participants were asked to walk somewhere convenient at a moderate pace that resulted in an increased heart rate and perceived exertion. They were asked to record all breaks in a daily log. The second intervention group (walking group) received a standard walking program aimed at increasing PA to a minimum of 30 minutes each day of moderate intensity walking in bouts of at least ten minutes. Behavioral feedback included steps that were measured using a pedometer with the goal of achieving at least 10,000 steps per day. To track their goal attainment, participants were asked to record their step count each day in a step log. The intervention began for all participants during a predetermined week at the end of February/beginning of March, 2013.

Outcome variables were measured four times during the study: pre-intervention, six weeks into the intervention, post-intervention, and three months post-intervention. Each participant received a phone call every two weeks to address any concerns or questions. Detailed records were kept throughout the study to measure adherence to the intervention and program effectiveness. Process evaluation methods used in this study are presented below and results of this evaluation are presented in the results section. Intervention outcomes will be discussed elsewhere.

Compliance with inclusion and retention criteria. As previously noted, potential participants were screened for inclusion and medical clearance was obtained for each prior to initiation of the program. Incentives for participation included a wellness assessment (fasting glucose, hemoglobin Ale, blood lipid measures, and body composition), health coaching, and a pedometer. Participants who consented to participate were tracked through each phase of the study. If they became unable or unwilling to continue their reasons for withdrawal were documented.

Implementation fidelity. Potential participants were scheduled for an initial visit to familiarize them with the study protocol and to assist them in completing study documents (i.e., informed consent form). A packet of forms was organized for participants before they arrived and a checklist was used to document that each form was completed by each participant. A checklist was also made to account for the key points that were explained to participants prior to pre-intervention testing (see Table 1).

Completion of online surveys. All participants were emailed hyperlinks to nine surveys at pre-intervention, post-intervention, and three months post-intervention. Online surveys were used for participant convenience. Email reminders with the survey links were sent periodically to remind participants to complete all the surveys. Records were kept related to survey completion.

Submission of break/walk logs. All participants were required to turn in electronic or hard copy activity logs during all testing sessions and throughout the intervention. A break was defined as a bout of at least two minutes of moderate intensity walking that interrupted sedentary time. Any interruption in sedentary time that was shorter than two minutes or below a moderate intensity was not counted. Members of the walking group were given a pedometer at the beginning of the intervention and were asked to keep weekly walk logs of how many steps they took each day throughout the program. Members of the breaks group were asked to record the number of breaks in sedentary time they took each day and did not receive a pedometer. Weekly logs were to be submitted by all participants and an email reminder was sent at the end of each week or beginning of the following week to promote compliance. Records were kept related to submission of activity logs.

Response to motivational and reminder emails. A separate email was sent to members of each group every week that included a motivational message and tip of the week. After each email was sent to participants, an automatic reply was sent to researchers to confirm successful/unsuccessful delivery of each email address. At the bottom of each email message, there was a link for the recipient to click if they read the message. If the link in the email was clicked, a second confirmation email was sent to the researchers to notify them that the email had been read. Each confirmation was recorded as documentation that the messages were delivered and read by participants. All motivational messages were sent to participants through an email address that they checked on a regular basis. Each motivational email included questions to allow participants to consider factors that affected their success in reaching their weekly goals. Participants also were asked to rate their success in achieving their break/step goal that week on a Likert scale (1-5), and were then asked to list strategies that allowed them to succeed. If they did not do well that week, they were asked to list strategies that could help them improve their behavior for the following week. If they responded to any part of those questions it was considered a response.

Participant satisfaction. Program satisfaction was evaluated through biweekly phone calls and an exit interview administered at the conclusion of the study. Phone calls were made to address participant progress and struggles with the program, talk about the weekly messages, provide encouragement, and discuss strategies that might help them make improvements. Five phone calls were made to each participant throughout the duration of the intervention. Personal visits were made instead of a phone call during mid-testing and at other times if participants had other concerns that needed to be addressed in person. Participants provided times that were convenient for them to receive these telephone calls. Content of phone conversations was typed on a computer as each conversation took place. The topics that were discussed included: how the participant felt the program was proceeding, specific successes or struggles of the participant, the participant's thoughts about the weekly messages, and additional participant comments.


Compliance with inclusion and retention criteria. Twenty-two participants (n=18 females) met the inclusion criteria. After orientation, one female participant withdrew without indicating a reason why she did not want to participate. Another female was withdrawn by the researchers because she could not be contacted following initial screening. One male participant withdrew following baseline measurements because he was going to relocate and would not be available to complete the study. The remaining participants (n=19) were randomly assigned to the breaks or walking group. After assignment one female participant was withdrawn by the researchers from the breaks group for not completing pre-intervention testing and another female withdrew from the walking group because she required foot surgery. In the course of the study, one final female participant withdrew from the breaks group, citing the difficulty of taking breaks on a consistent basis. Overall, eight participants in each group (total n=13 females) completed most measures for the intervention (84% retention rate).

Implementation fidelity. According to the checklist maintained by the researchers, all pre-intervention measures described in the methods were successfully administered to the 16 participants who completed the study. All participants were sent an email following their initial visits that reviewed each of the points covered in the initial visit. Important points pertaining to later sessions were reviewed as needed.

Completion of online surveys. All but one participant completed every survey at baseline (one participant did not complete one self-efficacy survey). The number of participants completing surveys decreased at the post-testing and at the three month follow-up. At post-testing, nine participants completed all surveys (56%), three completed at least one survey (75%), and four participants (25%) completed none of the surveys. The participants who did not complete the surveys were those who were struggling to comply with program requirements at the end of the intervention and were difficult to contact after the intervention. At the three month follow-up, only five participants started to complete the surveys and none completed all of them.

Submission of break/walk logs. Tracking and turning in activity logs on a consistent basis was difficult for most of the participants in this study. The number of logs that were turned in each week is presented on Table 2 and the number decreased as the intervention progressed. Those in the breaks group turned in fewer logs than those in the walking group. Members of the walking group were required to record the total number of steps they accumulated each day. This required much less effort than recording every break in sedentary time throughout each day.

Response to motivational and reminder emails. With the exception of week 11, all weekly messages were emailed on Thursday afternoon when participants were likely using email. Since participants emailed their activity logs on Monday, the researchers wanted to spread contact with participants throughout the week. Confirmation of receipt of emails was obtained for all participants for the first five weeks. From weeks six through twelve, there were four specific participants whose email did not send a confirmation of receipt. One of those participants responded to the emails on several occasions, so it is possible that all still received the emails. About half of the participants replied that they had read the email. Rates of participants who read and responded to the emails are shown in Table 3. Only about two to three participants provided a response (what is going well or what to improve) to the emails each week, with the exception of weeks one and three when more participants responded.

Participant satisfaction. Throughout the intervention, there were eight instances when participants were unable to be contacted for their biweekly phone call. In those cases a short message was left on their answering machine following at least four attempts across multiple days. With the exception of the participants who were unable to be contacted, only one occasion required more than two phone call attempts to make contact with a participant. When asked how the program was going, the most common response dealt with how busy each participant was and how they struggled to find time to walk or take breaks. Based on qualitative data, participants in the walking group consistently reported more enjoyment and satisfaction with the program compared to members of the breaks group. Members of the breaks group often mentioned how hard it was to get up hourly to take breaks throughout the day while they were at work mainly due to how busy they were.

Discussion and Implications

This study provides useful insight into the feasibility of implementing a 12-week walking program involving regular interruptions in sedentary time. Many of the lessons learned can be applied when planning programs to increase PA of participants who work in sedentary environments. Reaching and retaining more participants would allow the program to have a greater impact on the health of the university community. There are several thousand faculty and staff working in the university system who likely received the email announcement for the study. Employees can opt out of the email announcements, so it is unknown how many received or read the advertisement. However, there were likely many more who met the inclusion criteria who could have participated in the study, but chose not to join or were unaware of the study. Several participants dropped out due to reasons that could not be controlled (i.e., surgery or relocation), but those who failed to complete mid- or post-testing may have needed a more substantial incentive to continue. Including a direct financial incentive for participants, or an incentive provided by the university health insurance provider, may have attracted and retained more participants. An alternative approach could be to have a rolling enrollment for people who either wanted to start the program over again or who were not available to begin participation at the arbitrary time decided by the researchers. The online surveys were convenient for the participants and easy to administer, but it was difficult to motivate participants to complete them. Researchers were required to send many emails to some of the participants to remind them to complete the surveys. Online surveys are a superior way to collect, store, and analyze data because they are convenient, and the process eliminates errors associated with entering handwritten survey responses. However, if participants are not being compensated to complete all data collection activities, it may be more effective to administer surveys in a lab setting so that participants can ask questions and be encouraged to complete all surveys before they leave. This will increase the time required for their lab visits, but it will help ensure that data are collected from all participants at all measurement points.

As shown in Table 2, most participants submitted activity logs at the beginning of the intervention, but the number of submissions slowly tapered off as the program progressed. Participants were allowed to fill out the forms by hand and scan them in or to fill them out electronically and email them. This reduced the amount of mail and transit time required to receive logs from participants. Despite a reminder email being sent at the end of each week, it became increasingly difficult for some participants to keep up with the logs. It may be more effective to utilize an electronic database or a website/phone app where participants can enter information that is automatically submitted every day. Automated reminders could be sent if data were not entered that day so participants would be more consistent and not get behind. Tracking each interruption in sedentary time every day for the breaks group was impractical for most participants and another means such as a smartphone app or tracking device should be developed to track breaks without requiring participants to constantly record them.

Motivational emails were successfully sent and delivered each week, but all participants did not read and respond to them regularly. Since many of the participants were secretaries or in administrative positions, most of them used a computer frequently throughout the day and had access to the motivational messages and reminder emails. However, they also were very busy and may not have had much time to read and respond to the emails while at work. A Facebook page also was set up for each group, but was not effective due to the small number of participants that had a Facebook account. Increased motivation and adherence may be reached by allowing participants to choose from multiple options that work best for them, such as text messages, social media platforms, emails, or weekly meetings.

When speaking with participants and discussing successes and obstacles that made it difficult to take breaks or walk 10,000 steps, there were several recurring themes in the biweekly phone calls. The weather (i.e., excessive heat, cold, or wind) was mentioned multiple times as hindering progress in achieving the program goals. The weather was very windy and could get quite cold during the period when the study took place (February-May). Multiple participants reported getting acute illness during the intervention, which caused them to have abnormal weeks when they were not able to participate as they normally would. Generally, most participants said they enjoyed the program and that it was helpful to them. The post-intervention interviews were conducted when activity devices were collected. In several cases, the participants were taking time from their work day and did not have sufficient time to provide thoughtful answers. It is important to note that the program administrator was the one doing the interviews and phone calls so the participants could have provided biased answers, as they may not have wanted to disappoint the researcher.


An intervention designed to interrupt sedentary time may be an effective means of improving metabolic health in people with T2D instead of or in addition to a standard walking program. Much of the previous research that focused on reducing sedentary time used cross-sectional or designs that were feasible in the short-term (Gardiner et ah, 2011; Healy et ah, 2008; Cooper et ah, 2012). The current analysis provided insight into designing a long-term intervention to interrupt sedentary time among university employees who work in sedentary occupations. As noted previously, a similar study with a one week intervention decreased sedentary time and increased interruptions in sedentary time in older adults (Gardiner et ah, 2011). In longer interventions, it may be necessary to provide greater personalized guidance in the beginning to allow participants to evaluate how they can interrupt their sedentary time in a manner that is consistent with their job and lifestyle. Future research could incorporate technology to track and prompt participants when to interrupt sedentary time so that the intervention can be individualized to each participant.

Acknowledgement; The authors would like to thank the Healthy Sooners organization for providing support to complete this project.


Cooper, A. R., Sebire, S., Montgomery, A. A., Peters, T. J., Sharp, D. J., Jackson, N., & ... Andrews, R. C. (2012). Sedentary time, breaks in sedentary time and metabolic variables in people with newly diagnosed type 2 diabetes. Diabetologia, 55(3), 589-599. doi; 10.1007/s00125-011-2408-x

Funk, M., & Taylor, E. L. (2013). Pedometer-based walking interventions for free-living adults with type 2 diabetes; a systematic review. Current Diabetes Reviews, 9(6), 462-471.

Gardiner, P. A., Eakin, E. G., Healy, G. N., & Owen, N. (2011). Feasibility of reducing older adults' sedentary time. American Journal Of Preventive Medicine, 41(2), 174-177. doi: 10.1016/j. amepre.2011.03.020

Healy, G. N., Dunstan, D. W., Salmon, J., Cerin, E., Shaw, J. E., Zimmet, P. Z., & Owen, N. (2008). Breaks in sedentary time: beneficial associations with metabolic risk. Diabetes Care, 31(4), 661 666. doi:10.2337/dc07-2046

LaMonte, M. J., Blair, S. N., & Church, T. S. (2005). Physical activity and diabetes prevention. Journal Of Applied Physiology, 99(3), 1205-1213. doi:10.1152/japplphysiol.00193.2005.

Motahari-Tabari, N., Ahmad Shirvani, M., Shirzad-E-Ahoodashty, M., Youseh-Abdolmaleki, E., & Teimourzadeh, M. (2014). The effect of 8 weeks aerobic exercise on insulin resistance in type 2 diabetes: a randomized clinical trial. Global Journal Of Health Science, 7(1), 115-121. doi:10.5539/ gjhs.v7nlpl 15

Qiu, S., Cai, X., Schumann, U., Velders, M., Sun, Z., & Steinacker, J. M. (2014). Impact of Walking on Glycemic Control and Other Cardiovascular Risk Factors in Type 2 Diabetes: A Meta-Analysis. Plos ONE, 9(10), 1-8. doi: 10.1371/journal. pone.0109767

Sedentary Behaviour Research Network (2012). Letter to the editor: standardized use of the terms "sedentary" and "sedentary behaviours". Applied Physiology, Nutrition, And Metabolism, 37(3), 540-542. doi: 10.1139/h2012-024

World Health Organization. (2014). Global status report on noncommunicable diseases. ncd-status-report-2014/en/

Merrill Funk, PhD

E. Laurette Taylor, PhD

Paul Branscum, PhD

Craig Hofford, PhD

Allen Knehans, PhD

Howard Crowson, PhD

Susan B. Sisson, PhD

Corresponding Author: Merrill Funk, Ph.D., is an Assistant Professor at The University of Texas Rio Grande Valley in Brownsville, Texas. One West University Blvd., Department of Health and Human Performance SET-B 1.538, Brownsville, TX 78520, Ph: (956) 882-5994, Fax: (956) 882-7348,
Initial Orientation Checklist

Initial Orientation (paperwork)

Fill out Eligibility Criteria                               [check]

Read/sign Informed Consent + give copy                      [check]

Read/sign HIPAA + give copy                                 [check]

Fill out Contact Information Sheet                          [check]

Explain ID# (will be sent by email)                         [check]

Explain how to fill out surveys with ID# (should be         [check]
done before Health Screening)

Explain date for Health Screening                           [check]

Physical Activity Measurement (following                    [check]

Explain pedometer and accelerometer                         [check]

Explain position; both on right side (1st try               [check]
pedometer in line with right leg and acceler-ometer
next to it, can move to get correct readings on

Explain to wear pedometer/accelerometer for 7 days          [check]
during waking hours, no water activities

Explain to make sure both are right side up                 [check]

Go through calibration (set to zero, take 20 steps,         [check]
move until 20 is achieved)

Explain calibration on first morning and place              [check]
sticker over numbers for remaining time

Can wear devices under clothing                             [check]

Give "STOP" sign (if desired)                               [check]

Send email review of first day and subject number           [check]
with surveys


Break and Walk Logs

Week        1   2   3   4   5   6   7   8   9   10   11   12

BG (n=8)    6   7   6   6   5   4   5   5   5   4    4    2

WG          7   8   7   7   6   6   5   5   7   5    4    4

Daily logs turned in by members of the breaks group (BG) and
walking group (WG) through the duration of the intervention.


Email Read and Response Rates

Week        1     2     3     4     5     6     7     8     9    10

Read       86%   57%   69%   63%   50%   50%   63%   50%   50%   50%

Response   33%   38%   55%   30%   13%   13%   30%   25%   38%   25%

Week       11    12

Read       50%   50%

Response   25%   38%

Read Rate = Number of emails read/ number of emails sent

Response Rate = Number of emails responded to/ number of emails read
COPYRIGHT 2017 American Journal of Health Studies
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2017 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Funk, Merrill; Taylor, E. Laurette; Branscum, Paul; Hofford, Craig; Knehans, Allen; Crowson, Howard;
Publication:American Journal of Health Studies
Article Type:Report
Date:Jan 1, 2017
Previous Article:A mixed methods analysis of workplace health promotion at small, rural workplaces.
Next Article:Assessing the strategies of state offices of minority health to reduce health disparities.

Terms of use | Privacy policy | Copyright © 2018 Farlex, Inc. | Feedback | For webmasters