Short summary

Promoting physical activity is a first line choice of treatment for type 2 diabetes patients. However, there is a need for more effective tools and technologies to facilitate structured lifestyle interventions, and to ensure a better compliance, sustainability and health effectiveness of exercise training in patients with type 2 diabetes.

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Rationale

The InterWalk initiative and its innovative app for smartphones was developed by the Danish Centre of Strategic Research in type 2 diabetes aiming at implementing, testing and validating interval walking in type 2 diabetes patients in Denmark. The interval walking training approach consists of repetitive 3-minutes cycles of slow and fast walking with the intensity guided, based on the exercise capacity of the user. The individual intensity during slow and fast walking is determined by a short initial self-conducted and audio guided fitness test as well as  automated audio instructions aiming at motivating the individual to adjust intensity to the predetermined individualized walking intensities. The InterWalk data collected prospectively in all users will be linked to the unique Danish nationwide databases and administrative registries, allowing extensive epidemiological studies of exercise in T2D patients including level of adherence to InterWalk training as well as long-term effectiveness surveys of important health outcomes including cardiovascular morbidity and mortality. As of May 2016, the InterWalk app has been downloaded by >27.000 persons and the achieved epidemiological data quality is encouraging. Of the 9466 persons providing personal information, 80% of the men and 62% women were overweight or obese (BMI above or equal to 25). The InterWalk project represents a contemporary technology-driven public health approach to monitor real life exercise adherence, and to propagate improved health through exercise intervention in T2D and other patient groups and in the general population.

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Description of the cohort

The app Version 1.0 was released in AppStore in November 2013 and a subsequent test of unsupported use was performed and evaluated by observations and focus group interviews (n=25) in collaboration with the Danish Diabetes Association. The participants found the InterWalk app to be manageable and meaningful in their everyday life. However, there was a need for an extension of the help function, an increased focus on retaining the quality of the exercise, and an automated data upload function from iPods. Finally, based on the user feedback from the therapists in three Danish municipalities, the current version was updated with an increased volume of the audio and voice feedback. This version of InterWalk was released to AppStore in December 2015. This trial has been registered with the NCT under number NCT01234155.

An updated version 3.0 will be released march 2017. 

Data and biological material

Variables:

• Acceleration (Accelerometer)
• Geographical location (GPS)
• Intensity cutoffs (Accelerometer)
• Distance covered (GPS)
• Frequency of use (Upload)
• Training duration (Accelerometer)
• Quality of IWT (Accelerometer)
• Steps (Accelerometer)
• Body height (self-report)
• Body weight (self-report)
• Sex (self-report)
• CPR (self-report)
• Name (self-report)

Collaborating researchers and departments

Department of Endocrinology, Odense University Hospital, Odense, Denmark

• Jens Steen Nielsen

Department of Infectious Diseases, Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen; The Danish Diabetes Academy, Odense University Hospital and Department of Infectious Diseases, Centre of Inflammation and Metabolism, Rigshospitalet, University of Copenhagen

• Mathias Ried-Larsen

The Danish Diabetes Academy, Odense University Hospital and Department of Clinical Epidemiology, Aarhus University Hospital

• Reimar W Thomsen

Department of Infectious Diseases, Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen and Department of Endocrinology (Diabetes and Metabolism), Rigshospitalet, University of Copenhagen

• Cecilie F Brinkløv
• Charlotte Brøns

Department of Infectious Diseases, Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen and CopenRehab, Department of Public Health, Section of Social Medicine, University of Copenhagen, Copenhagen

• Laura S Valentiner
• Henning Langberg

Department of Infectious Diseases, Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen and Department of Infectious Diseases, Centre of Inflammation and Metabolism, Rigshospitalet, University of Copenhagen

• Kristian Karstoft
• Bente K Pedersen

Department of Infectious Diseases, Centre for Physical Activity Research, Rigshospitalet, University of Copenhagen; The Danish Diabetes Academy, Odense University Hospital and Department of Endocrinology (Diabetes and Metabolism), Rigshospitalet, University of Copenhagen

•  Allan A Vaag

Publications associated with the project

Implementation of interval walking training in patients with type 2 diabetes in Denmark: rationale, design, and baseline characteristics / Ried-Larsen M, Thomsen RW, Berencsi K, Brinkløv CF, Brøns C, Valentiner LS, Karstoft K, Langberg H, Vaag AA, Pedersen BK, Nielsen JS; Clinical Epidemiology, 8 June 2016 Volume 2016:8 Pages 201-209.

Criterion validity and reliability of a smartphone delivered sub-maximal fitness test for people with type 2 diabetes / Brinkløv CF, Thorsen IK, Karstoft K, Brøns C, Valentiner L, Langberg H, Vaag AA, Nielsen JS, Pedersen BK, Ried-Larsen M; BMC Sports Science, Medicine and Rehabilitation Oct 7 2016.