Degree Type


Date of Award


Degree Name

Master of Science



First Advisor

Greg Welk


Lack of physical activity is one contributing factor to the obesity epidemic currently affecting the United States. Increasingly sedentary jobs have added to this societal lack of activity, so worksites are a promising location for interventions to increase physical activity. Such interventions have shown mixed results and can be costly. New technologies including self-monitoring devices, text messaging reminders, and online health coaching are promising tools to improve such interventions. The purpose of this study was to determine the effectiveness on increasing physical activity of employees in a worksite setting of the combined use of a self-monitoring device (SWA) along with text messaging prompts and online health coaching compared to the effectiveness of the SWA independently.

Fifty-seven subjects (14 males and 46 females) completed one of two 8-week interventions. Group 1 (n = 27) received a self-monitoring tool called the SenseWear Armband (SWA) and guidance on its use, while Group 2 (n = 30) received the SWA along with text messaging reminders to be active and behavior change support through online health coaching using the ProConnect Software tool. Physical activity was assessed with two instruments (7 day Physical Activity Recall and the Global Physical Activity Questionnaire) and scored in terms of average daily MET minutes of MVPA (MetMin). Two psychological constructs (self-efficacy and autonomy) were also assessed to capture possible changes in psychosocial factors. All measures were obtained at both baseline and at the completion of the intervention and the changes over time in each outcome were assessed with 3-way (Condition x Trial x Gender). The magnitude of effects were reported using effect sizes.

The results did not reveal any significant Condition x Trial interactions for the physical activity variables but a significant Condition x Trial x Gender interaction revealed differential outcomes for males and females. Significant increases in Met-Min were observed for the 7-day Physical Activity Recall measure in Group 2 while decreases were evident in females. This effect was not evident with the other activity measure or with the psychosocial indicators. The associations between the physical activity measures and the psychosocial outcomes were also weak.

Findings from this study suggest that text messaging reminders in combination with a self-monitoring tool may be effective in assisting motivated males to increase their physical activity behaviors. The differing results between sexes point to the importance of tailoring interventions not only to different sexes, but also potentially to the personality characteristics, needs, and desires of each individual. Longer term studies may be warranted to gain a better understanding of the effectiveness of self-monitoring tools and associated technologies for worksite health promotion.

Copyright Owner

Molly Webb



File Format


File Size

70 pages